Treffen der FledermausforscherInnen in
Deutschland 2017
Bild: Sönke von den Berg
06. – 08. Januar 2017
Vallendar
1
Abstracts
Freitag (06. Januar 2017)
16:00 Environmental acoustic cues guide the biosonar attention of the greater horseshoe bat.
1
Acoustic and Functional Ecology Group, Max Planck Institute for Ornithology, Seewiesen, Germany *
current address: Neurogenetics of Vocal Communication Group, Max Planck Institute for
Psycholinguistics, Nijmegen 6525 XD, The Netherlands
Echolocation is a highly sophisticated sensory system for actively probing light-deficient
environments. However, due to the directional and stroboscopic emission of calls and the strong
attenuation of ultrasonic frequencies, sensory acquisition by biosonar is limited both spatially
and temporally. We hypothesise that this limitation will favour the opportunistic use of
additional information for general perception of surroundings, and that mammals that use
biosonar to hunt likely exploit a wider range of environmental information than previously
believed. We tested this hypothesis in greater horseshoe bats (Rhinolophus ferrumequinum),
whose echolocation is specialised for the detection of fluttering insects, but spatially strongly
limited due to high call frequencies. We predicted that bats will react to passive acoustic cues,
such as prey-generated rustling sounds, by steering their sonar beams towards the origin of the
sound for further biosonar-based evaluation. In our first experiment, bats heard the sound of a
moth fluttering in vegetation (or phase-randomised or amplitude-inverted versions of the
recording to control for temporal and spectral cues). In our second experiment, we
simultaneously presented a rustling sound with one of the control stimuli. Bat echolocation calls
were recorded on a spatial microphone array to evaluate the number, intensity and direction of
calls. Generally, bats scanned the room with their sonar beam, but directed it towards the sound
source during playback; some individuals even towards the control sounds. Our results show
that passive acoustic information guides the spatial pattern of information acquisition by
echolocation. Akin to cross-modal integration, these echolocating mammals thus possess
cognitive mechanisms to integrate environmental cues with actively generated echoinformation, enlarging perceived space beyond the reach of biosonar.
2
16:15 Echolocation in Myotis myotis while approaching aerial targets of differing target
strength.
Sonja Sändig, Annette Denzinger, Hans-Ulrich Schnitzler
Animal Physiology, Institute for Neurobiology, University of Tübingen
Myotis myotis, the greater mouse-eared bat, belongs to the guild of passive gleaning bats. It
forages mainly ground-dwelling prey by relying on prey-generated rustling noises. In our
experiment, however, four M. myotis were trained to catch in flight tethered targets in the aerial
mode by using echolocation. We randomly offered mealworms and an artificial reflector and
thus presented targets of different reflection properties to the bats. Echolocation calls were
recorded with an on-board telemetry microphone and flight behavior was recorded with video
cameras for 3D reconstruction of flight path. Flight behavior didn’t differ when approaching the
targets of various target strength and looked the same as is known from other bats foraging in
the aerial mode. When approaching the louder reflector bats started to reduce pulse interval and
emission-SPL in a greater target distance as if approaching the lower mealworm. Thereby, SPL
reduction is dependent on target properties: When approaching the reflector, bats reduced SPL
with a lower rate per halving distance as if approaching the mealworm and all bats tended to
reach a mean SPL of 60-77 dB at the end of buzz I no matter what target type was offered. We
unfortunately could not record any echoes of the targets but nevertheless could calculate the
echo-SPL on the basis of the targets’ ensonification results. Our study shows that the increase of
echo-SPL and also the decrease of emission SPL during the bat’s approach to the target is
different with different targets and thus different reflection properties. We therefore conclude
that the increase of echo-SPL during an approach encodes information on the target type and its
reflection properties. Finally, we conclude that the measured reduction of emission-SPL depends
on range and cannot be explained by a tight feedback control system that keeps the echo SPL at
a specific reference value.
3
16:30 Echolocation behavior of phyllostomid bats
Gloria Gessinger1, Annemarie Surlykke2, Signe Brinkløv2, Marco Tschapka1,3
1
Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm
2
Institute of Biology, University of Southern Denmark
3
Smithsonian Tropical Research Institute
Neotropical Leaf-nosed bats (Phyllostomidae) show a huge range of feeding habits; nonetheless
most of them utilize very similar echolocation calls. The presence of often very prominent
noseleaf structures led to the assumption that echolocation calls in phyllostomids are exclusively
emitted through the nostrils. However, preliminary observations indicated that phyllostomid
species fly regularly with an open mouth. Analyzing videos from a high-speed camera with
synchronized ultrasound recordings we screened 22 phyllostomid species in Panama under
standardized conditions for their echolocation behavior. Two types of echolocation behavior
where defined: open mouth emission and nasal emission. The results showed that echolocation
behavior differed distinctly between the subfamilies: Frugivorous Carolliinae, nectarivorous
Glossophaga soricina (Glossophaginae) and sanguivorous Desmodus rotundus
(Desmodontinae) flew consistently with open mouth, as did most of the animalivorous
Glyphonycterinae, Micronycterinae and Phyllostominae, with the interesting exception of two
species from the omnivorous genus Phyllostomus, which consistently flew with closed mouths.
Frugivorous Stenodermatinae also flew always with closed mouths and therefore emitted the
echolocation calls exclusively through the nostrils. Spectral and temporal echolocation call
parameters and intensity did not differ significantly between the two groups. However, head
position angles differed significantly between nasal emitters and open mouth emitters, with nasal
emitters pointing the nostrils, and open mouth emitters the mouth and nostrils, in the direction
of flight. Based on the consistent differences among subfamilies, we suggest that not all
phyllostomids are exclusively emitting echolocation calls through the nostrils and that
echolocation call emission within the family is more diverse than previously thought. However,
further experiments, such as selectively obstructing sound emission through nostrils or mouth,
respectively, are necessary to clarify if and to what extent open mouth emitters are emitting
sound also through the nostrils.
4
16:45 Breaking the waves: how bat biosonar perceives spatial and temporal frequency
Leonie Baier1,2, Lutz Wiegrebe1
1
Department Biology II, Ludwig Maximilians University Munich, 82152 Martinsried, Germany
Acoustic and Functional Ecology Group, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany
2
Many bats from diverse taxa have specialised in trawling prey from water surfaces. Trawling
bats foraging on agitated water surfaces must process both the structure and the movement of
the waves, i.e. the waves’ spatial and temporal frequency. In the first chapter of my PhD, I have
explored biosonar’s sensitivity to spatial frequency. While a still water surface exposes a floating
prey item, an agitated water surface reflects echoes that mask prey-generated echoes. My
findings imply that bats can circumvent this masking effect by applying a perceptual high-pass
filter for spatial frequency and segregate prey from background according to spatial frequency.
In this presentation I focus on the second chapter of my PhD, where I look into biosonar’s
sensitivity to temporally variant structures. The auditory system excels in the measurement of
infinitesimal temporal differences. Echolocating bats measure the time delay between the
emission of their calls and the returning echoes (in short, echo delay) in order to determine the
distance to the ensonified object. However, with the analysis of temporal frequency bat
echolocation faces special challenges: firstly, it is not continuous but stroboscopic. A bat calls,
then must be silent in order to hear the returning echo. For most FM bats the duty cycle of sonar
ensonification is typically less than 10%. For fast periodic changes an echolocating bat may thus
run into aliasing problems, i.e. a systematic perceptual error. Secondly, for FM bats, call
durations do not exceed a few milliseconds, thus variations in echo delay must be sampled across
a sequence of echolocation calls. Variations of echo delay over time have been introduced in the
classical phantom-target jitter experiments by Simmons (1979), where one virtual target was
presented at a fixed delay and the second target was presented at delays that varied from call to
call. In these experiments, the temporal frequency was determined by the rate of sonar emissions
and thus not studied as an independent parameter. More recently, Goerlitz et al. (2010)
investigated Glossophaga soricina bats’ sensitivity to the magnitude of a temporal frequency for
a single fixed, i.e. call-rate-independent, modulation frequency of 10 Hz, determining a
threshold of 73µs echo delay variation.
In the current study, we have extended the experiment by Goerlitz et al. by testing a wider range
of modulation frequencies, from 5 Hz to 1000 Hz, in the bat Phyllostomus discolor. Bats have
been trained to discriminate a rewarded virtual target, where the echo delay is constant, from an
unrewarded target, where the echo delay was sinusoidally modulated at an adjustable frequency
and magnitude. The delay modulation was independent of the call rate, and the sounds presented
by the speakers were always real-time generated echoes of the bat’s emissions. We have derived
psychometric functions as a function of modulation magnitude for eight different modulation
frequencies. Our results show that detection thresholds are not monotonous as a function of
modulation frequency. While bats’ sensitivity can be as good as ±30µs echo delay variation at a
modulation frequency of 1000Hz, it can be as bad as ±800µs echo delay variation at a modulation
frequency of 20Hz. For modulation frequencies below 20 Hz, detection thresholds improve
again. These results are discussed with respect to different perceptual cues available to the bats,
especially the interplay of modulation frequency and inter-call-interval. To our knowledge, this
study is the first to systematically evaluate biosonar sensitivity to the magnitude of an object’s
temporal frequency.
5
17:00 Scanning of echo-acoustic flow in the bat Phyllostomus discolor
Kathrin Kugler, Lutz Wiegrebe
Movement directly influences our perception of space. This direct link between movement and
sensory perception has received much attention in the visual system. Here, movement like we
experience it for example in a roller coaster or when looking out of a moving train, induces
optic flow that in turn elicits saccadic eye movements. These fast, dart-like movements of the
eyes allow rapid reorientation of the foveal focus and thus an expansion of the area that is
scanned. Flow fields contain essential information on the spatial arrangement of objects, as
well as on the distance between the observer and the objects. However, this information is
encoded not only in optic flow fields. Echolocating bats navigate elegantly through complex
environments in pitch darkness, and flight guidance is affected by echo-acoustic flow. Previous
work on the echolocation system has focused mainly on the extraction of temporal and spatial
parameters for 3D reconstruction of the immediate environment in static situations. However,
to date the empirical investigation of the perception and neural representation of dynamic
changes in these parameters is insufficient. In this study we investigate in a tightly controlled
behavioral experiment how bats employ their echolocation system when scanning echoacoustic flow. To this end, we monitor and reconstruct in 3D both a close-up of the facial
structures, including the motile nose leaf and outer ears, as well as the sonar-beam axis of the
bat while it is moved along structured surfaces. The results demonstrate a temporal correlation
between the emission of echolocation calls and movements of the nose leaf as well as
movements of the outer ears while calls are emitted at altering sonar beam axes. The callcorrelated movements of the facial structures may lead to a higher directionality of the
echolocation system and may enable the bat to adjust their echo acoustic gaze to dynamic
environments.
6
17:15 Modelling Sensory Collisions in Bat Aggregations
Thejasvi Beleyur1, Claire Guérin1,2, Holger R. Goerlitz1
1. Acoustic and Functional Ecology Group, Max Planck Institute for Ornithology, Seewiesen
2. Erasmus Mundus Master Programme in Evolutionary Biology
Echolocating bats are ideal to study the strategies of sensory systems when faced with difficult
and conflicting cues. They sense their surroundings by emitting loud calls and listening for the
faint returning echoes, which they then use to navigate. Numerous studies to date have shined
light on how individual bats process the multitude of returning echoes in complex
environments while performing intricate maneuvers of prey capture or obstacle avoidance.
However, most bat species are social and often fly and echolocate in the vicinity of other
individuals as in common foraging grounds. This brings about the potential for ‘sensory
collisions’ – where the loud calls of a conspecific mask incoming echoes. These sensory
collisions are bound to increase with increasing group sizes, and could seriously hamper
effective sensing of the surroundings through echolocation.
Many species exhibit different responses to sensory collisions – such as increased inter-pulse
intervals, shortened calls, altered frequency content in calls, and even combinations of these.
However, a generalised framework to understand the psychoacoustical basis of these varied
behaviours is lacking to date. In our simulations, we quantify sensory collisions in bat
aggregations, where a sensory collision is defined as the temporal overlap of an incoming
foreign call and an own echo. Using agent-based models, we analyse the extent of sensory
collisions resulting from individuals in a group adopting temporally related strategies that vary
call parameters such as call duration, inter-pulse interval and duty cycle. To understand
sensory collisions in a range of behavioural and ecological contexts we analyse the effect of
group size, inter-individual distance and source level. Finally, to dissect the spatial
contribution of bat calling and hearing to sensory collisions, we implement directionality in
calling and hearing with experimentally derived piston models and head-related transfer
functions. The results of these directionally calling and hearing bats are compared to a null
model with omnidirectional hearing and frontal calling.
Our agent-based simulations provide a generalised and flexible framework to analyse the
auditory inputs an individual bat could be receiving as it flies in the midst of other bats.
Though we parametrise our models with reference to the locally found Myotis daubentonii, the
simulation environment presents a flexible approach for exploring the underlying sensory basis
behind the calling behaviour of multiple echolocating bat species.
7
17:30 'The BATLAS' online brain atlas: how neuro-genetic mapping can help us
understand bat vocal behaviour
Pedro Rodenas-Cuadrado1, Janine Mengede1, Michael Yartsev2, Uwe Firzlaff3 and Sonja C.
Vernes1, 4
1
Max Planck Institute for Psycholinguistics, PO Box 310, Nijmegen, 6500 AH, The Netherlands
Department of Bioengineering, Helen Wills Neuroscience Institute, Li Ka Shing Center, UC Berkeley, Berkeley,
CA 94720-3370, California, USA
3
Lehrstuhl für Zoologie, TU München, Liesel-Beckmann-Str. 4, Freising-Weihenstephan, München, 85350,
Germany
4
Donders Centre for Cognitive Neuroimaging, Kapittelweg 29, Nijmegen, 6525 EN, The Netherlands
2
Bats employ a highly sophisticated vocal repertoire for navigating their environment and
communicating in a social context and some species have also shown evidence for vocal
learning. As such, bats present an exciting opportunity to study the behavioural and genetic
underpinnings of vocal communication. Given that vocal learning is a crucial component of
spoken language acquisition, such studies may also offer insight into the basis and evolution of
human spoken language.
Exploring the genetic basis of vocal communication in bats requires knowledge of the neurogenetic properties of bat brains; however limited information regarding this is currently
available. To address this gap we have comprehensively mapped the expression of key genes
implicated in human speech and language in the brains of two vocal learning bats, Phyllostomus
discolor and Rousettus aegyptiacus. We uncovered remarkably high conservation in the
expression patterns of FoxP1, FoxP2 and CntnaP2 between bats and humans, strengthening the
promise of bats for modelling neuro-genetic mechanisms underlying spoken language. This
neurogenetic bat atlas (“The BATLAS”) has been made into a publicly accessible online
resource where data can be browsed or searched and high resolution images can be directly
viewed. In the future we aim to expand this resource with further gene sets and bat species.
Understanding the neuro-molecular properties of these bats will facilitate further cross-species
comparisons of gene expression patterns and molecular and functional properties of specific
brain regions. The BATLAS will also open the way for manipulations of these genes in bats,
allowing brain regions in which a gene is highly expressed to be specifically targeted with
genetic tools. Such genetic manipulations will be a powerful approach for determining how
genes contribute to vocal behaviours. For these reasons, The BATLAS will be an important
resource for bat researchers interested in the neuro-genetic underpinnings of vocal behaviour.
8
17:45 Flower visitation behavior of nectar-feeding bats changes in response to overall
floral resource availability
Jan Bechler1, Marco Tschapka1,2
1
University of Ulm, Institute of Evolutionary Ecology and Conservation Genomics, Germany
Smithsonian Tropical Research Institute, Balboa, Panama
2
Many bats species face an extremely high energy turnover due to an unfavorable body-surfaceto-volume ratio. This is especially true for nectar-feeding bats that obtain their food in tiny
portions with some bats consuming in a single night more than 100 % of their body weight
during up to 1.000 flower visits. Therefore, nectar bats experience a high selective pressure on
efficient foraging strategies and are expected to be highly sensitive to changes in local resource
availability. In the Caribbean lowland rainforest of Costa Rica nectar-feeding bats face two
distinct seasons of flower availability: a main season with a sequence of several high-quality
bat-pollinated plants and a low season when mainly flowers of the steady-state flowering
Solanaceae Merinthopodium neuranthum are present. However, these are not very abundant,
they produce a modest amount of nectar only during the first half of the night, and the nectar is
of relatively low energetic content.
We were interested how bats adapt their nightly foraging behavior to nectar production
patterns in M. neuranthum and how bats respond to the presence of more profitable flowers in
the habitat. Fieldwork took place at La Selva Biological Station, Costa Rica. We used infrared
video cameras to monitor bats visits at Merinthopodium flowers from August, when these were
the main energy resource for nectar-feeding bats, until November, when the bromeliad
Werauhia gladioliflora as the first of several high-quality bat-pollinated plants had started
flowering. Visitation behavior was correlated with nectar secretion pattern and compared
between seasons with different floral resource availabilities.
Bats showed a high ability to adjust their nightly visitation behavior to nectar availability in M.
neuranthum and responded to decreasing energy availability with less frequent, but longer
visits. Further, when more profitable flowers were available, M. neuranthum became less
attractive for nectar-feeding bats and flowers were visited less frequently. Hence, nectarfeeding bats are highly sensitive to changes in resource availability and preferably visit the
most profitable flowers available. This indicates the possibility of a competition for pollination
services among bat-pollinated plants based on nectar traits.
9
Samstag (07. Januar 2017)
08:45 Hearing sensitivity after acoustic over-stimulation in P. discolor
Meike Linnenschmidt, Uwe Firzlaff, and Lutz Wiegrebe
Echolocation and communication sounds of bats, especially in large aggregations or during
flight, can reach such high sound levels, which would undoubtedly affect the hearing abilities
of most animals when exposed over longer periods. Latest studies in bats suggest a unique
adaptation of the bats’ auditory system to prevent such impairments (Simmons et al 2016,
Hom et al 2016). In these studies, however, bats were awake and thus they could simply turn
away from the sound source and activate their middle ear reflex to conserve inner-ear
functions. Such processes are disabled under anaesthesia. Here, anaesthetised bats are exposed
to intense (140 dB SPL) frequency modulated sweeps (1-45 kHz) played back in a continuous
loop up to 2 h. Hearing sensitivity is evaluated prior and after acoustic over-stimulation by
means of auditory brainstem responses in reply to short broadband clicks (5 to 90 kHz) and
short (2.5 ms) tone pips with carriers between 5 and 90 kHz. First results demonstrate the
absence of any auditory brainstem response to clicks and tone pips with sound levels up to 130
dB (peak equivalent SPL) immediately after the acoustic over-stimulation. Thus, hearing
sensitivity shifted upwards by minimum 50-70 dB across all frequencies tested when compared
to thresholds prior to acoustic exposure. This loss in hearing sensitivity could be either
temporary and consequently recover fully or partly over time, or the loss could be permanent,
with dramatic impact on the bats’ echolocation and communication abilities. Hearing tests
conducted every 14 days for up to 3 months after the exposure will reveal further insight in the
plasticity of the bats’ auditory system after noise exposure with high sound levels. This
paradigm is suitable to test whether bats have indeed novel mechanisms to conserve inner-ear
functions in exceedingly loud environments.
10
09:00 Target‐distance processing in the presence of masking noise.
Authors: M. Jerome Beetz, Sebastian Kordes, Julio C. Hechavarría, Manfred Kössl
Authors’ affiliations: Institute for Cell Biology and Neuroscience, Goethe University, 60438
Frankfurt/Main, Germany
Echolocation allows bats to orientate in complete darkness, making short-range orientation
light independent. Despite being an elegant adaptation to a nocturnal lifestyle, echolocation
can be extremely challenging under some situations. For accurate orientation, bats have to
distinguish their own echoes from echoes of conspecifics. When flying, bats are never facing
an acoustically silent environment. There are multiple natural low and high frequency sources
that could potentially jam or mask echo perception and thus orientation.
The present study addresses the question of how acoustic noise from conspecifics, different bat
species, or locusts affects echolocation behaviour and neuronal processing in cortical and
collicular neurons that are sensitive to high frequencies. In a behavioral paradigm echolocation
performance of the fruit-eating bat Carollia perspicillata was assessed in the presence and
absence of jamming sounds. The results show that echolocation performance does not seem to
be overly affected by jamming noise. Behaviorally, the bats are decreasing the minimum pulse
interval and are producing more complex pulse patterns (higher percentage of sound strobes)
when flying in a noisy surrounding. To investigate the impact of jamming sounds on neuronal
response patterns, collicular and cortical neurons were recorded in awake and passively
listening bats. Neuronal responses to echolocation sequences of C. perspicillata were assessed
in the presence and absence of different jamming sounds. Despite being sensitive to the
jamming sounds, some neurons were still capable of responding to the behaviorally relevant
echolocation streams.
11
09:15 Auditory stream segregation and object representation in complex echo-acoustic
flow fields
Wolfgang Greiter1, Uwe Firzlaff 1
1Lehrstuhl für Zoologie, Technische Universität München, Liesel-Beckmann-Str. 4, 85354 Freising,
Germany
Echolocating bats use the echoes of their sonar emissions to determine position and distance of
objects or prey. Target distance is represented in a chronotopically organized map of echo
delay in the auditory cortex (AC) of bats. During flight in complex environments streams of
echoes are reflected from multiple objects along the flight path. To separate sounds from
specific objects in such streams is a challenging task for the auditory system of bats as well as
many other animals.
We combined naturalistic call/echo sequences simulating a bat’s flight in virtual acoustic space
with extracellular recordings in the AC of anaesthetized bats (Phyllostomus discolor). We
found neurons that selectively focused to echoes from only one object in a complex stream of
echoes originating from two different objects along a virtual flight path. The objects were
processed sequentially in the order of object approach. We further varied the temporal pattern
of sonar emission during the simulated flight sequences to test its influence on cortical object
representation. The detailed representation of an object in the cortical target range map was not
fixed but could be dynamically adapted depending on temporal patterning of call/echo pairs
during target approach within the flight sequence.
Our results show that neurons in the AC of bats can separate different streams of echoes and
focus their response to specific objects in a complex naturalistic flight sequence, depending on
the dynamic variation of sonar information (i.e. echo-acoustic flow) during flight. Therefore,
stream segregation in mammals can be based on the integration of multiple dynamically
changing acoustic parameters.
This work was supported by a DFG-Grant (FI 1546/4-1) to U. Firzlaff.
12
09:30 The neural basis of dim-light vision in echolocating bats
Susanne Hoffmann1, Alexandra Bley2, Mariana Matthes2, Annika Quader2, Uwe
Firzlaff2 and Harald Luksch2
1 Max-Planck-Institute for Ornithology, Department of Behavioural Neurobiology,
Eberhard-Gwinner-Strasse, 82319 Seewiesen
2 Technische Universität München, Chair of Zoology, Liesel-Beckmann-Str. 4, 85354
Freising-Weihenstephan
Echolocating bats mainly rely on their biosonar system for orientation during twilight.
But biosonar can be supported by vision, as many bat species have large eyes that
are well adjusted to low light levels. Thus the question arises, what neural
mechanisms that further facilitate the use of visual information under dim-light
conditions may exist in these nocturnal animals? Surprisingly, the neural capabilities
of the bat visual system have not been investigated, so far.
We probed the superficial layers of the superior colliculus of the omnivorous bat
Phyllostomus discolor and discovered three neural features that most likely contribute
to the ability of echolocating bats to exploit visual information under dim-light
conditions: 1) extremely wide spatial receptive fields of visual neurons enable spatial
summation of visual information, which improves the sensitivity of the visual system.
2) comparably short neural response latencies provide good temporal resolution,
which is important for a fast flying nocturnal animal. 3) strong oscillations in neural
responses may mediate synchronization of activity within and between different
levels of the bat’s visual system and thus enhance the effectiveness of visual input.
Given that knowledge about neural adaptations to dim-light vision is mainly based on
studies done in non-mammalian species, our novel data provide a valuable
contribution to this field. In addition, we could demonstrate that omnivorous bats
represent a so far unknown but promising animal model to study the
neurophysiological aspects of dim-light vision in nocturnal mammals.
13
10:15 On the occurrence of ultra-rough amplitude modulations in the distress calls of
bats
Julio Hechavarria, Lisa Martin, Anna Huber, Jerome Beetz, Manfred Kössl
Affiliation: Institut für Zellbiologie und Neurowissenschaft, Goethe-Universität, Frankfurt/M., Germany. Abstract
Communication calls are ubiquitous throughout the animal kingdom, where they play a role in
advertising physiological states and/or socio-contextual scenarios. Several types of
communication calls have been described according to the context in which they are produced.
Aggression calls, for example, are typically uttered in distressful scenarios such as agonistic
interactions. Recently, it was reported that differences between aggression and non-aggression
calls exist at the level of temporal amplitude modulations (AMs). For example, human screams
(a type of agonistic vocalization) carry fast AMs at frequencies above 100 Hz, as opposed to
non-screamed vocalizations that are temporally modulated at lower frequencies. Sounds that
contain fast AMs are typically defined as “rough” and they have been found in the agonistic
vocalizations of numerous animal groups, including humans and several bird species. The
main aim of this study was to test whether “rough” amplitude modulations are a distinctive
feature of agonistic calls emitted by another highly vocal animal group: the bats. Our
hypothesis was that if rough agonistic vocalizations are a generalized trait across vertebrates,
then, bat distress calls should be rougher than other vocalizations produced by these animals in
non-aggression contexts, such as echolocation. To test this hypothesis, we studied the temporal
modulation envelope of 5291 distress syllables uttered by 13 adult bats (6 females and 7
males) of the species Carollia perspicillata. We found that ~ 58 % (3080/5291) of the distress
syllables carry clear fast amplitude modulations at frequencies close to 1800 Hz. These
vocalizations could be classified as rough, and they appear intermingled with non-rough
vocalizations in the bats’ distress broadcasts. The AM frequency observed in C. perspicillata’s
rough distress utterances is much higher than that found in other animal species such as birds
and humans, in which rough vocalizations are typically modulated at frequencies bellow 500
Hz. The AM frequency of C. perspicillata’s rough distress vocalizations is also higher than
AM frequencies found in biosonar calls of the same species, but it is well-below carrier
frequencies used by C. perspicillata for echolocation and communication purposes.
14
10:30 Individual recognition of social group members in free-living bats
Mirjam Knörnschild, Maria Eckenweber, Martina Nagy
The ability to recognize conspecifics individually plays a crucial role in shaping animal
societies and is considered to be cognitively more advanced than class-level recognition (e.g.
discriminating familiar vs. unfamiliar conspecifics). Under natural conditions, vocal individual
recognition has predominantly been studied in primates, despite its importance for other
mammalian taxa. Here, we present experimental evidence that wild bats, Saccopteryx
bilineata, can recognize individual group members using voice cues in distress calls. Bats
produce distress calls when being caught by a predator, and distress calls often attract
conspecifics. We conducted a distress call playback experiment in direct vicinity of the bats’
day-roost during which we simulated predation events that were either congruent or
incongruent by using a modified violation-of-expectation paradigm. Bats approached the
speaker broadcasting distress calls of group members only when the simulated scenario was
congruent (when the stimulus donor had already left the roost), but never when the simulated
scenario was incongruent (when the stimulus donor was still perched among the focal bats).
Thus, distress calls only elicited a relevant behavioral response (phonotaxis) when the
expectation about the signaler’s position was not violated. The lack of responsiveness when
conflicting information was presented (i.e. the physical presence of an individual in one place
and its voice in another place) strongly suggests that S. bilineata is capable of recognizing
individual conspecifics based on voice cues in distress calls. Our study shows that experiments
with a modified violation-of-expectation paradigm are a promising approach to study the
cognitive abilities of free-living bats.
15
10:45 Two types of social calls indicate food source defense in foraging P. pipistrellus
Simone Götze, Annette Denzinger, Hans-Ulrich Schnitzler
Animal Physiology, Institute for Neurobiology, University of Tübingen
Complex social calls of common pipistrelle bats are known to be emitted in agonistic behavior
to display food source defense in presence of other bats. In sound recordings of free flying
Pipistrellus pipistrellus complex social calls have been accompanied by a so far undescribed
short frequency modulated call type of high terminal frequency. The study aimed to determine
whether these high frequency calls may serve a social function.
The flight and acoustic behavior of free flying pairs of P. pipistrellus foraging around streetlights
was recorded with four microphones. Interactions between bats were analyzed by reconstructing
their three-dimensional flight paths and measuring parameters of associated signal emissions.
Inter-individual distances and angles between flight paths of the bats during emission of both
call types were determined and compared statistically. In presence of a conspecific the resident
emitted agonistic complex social calls at inter-individual distances of ~12 m (2-21 m) and high
frequency calls at significantly shorter inter-individual distances of ~7 m (1-24 m). The median
angle between the flight direction of the resident and the direction to the intruder was
significantly larger at complex social call emissions (~77°, 24-173°) than during high frequency
call emissions (~42°, 5-112°). High frequency calls were emitted as single calls or in groups of
two or three with terminal frequencies of 56.7 ± 2.2 kHz and durations of 3.3 ± 0.3 ms (mean ±
standard deviation). High frequency calls were emitted only by the resident and often associated
with chasing flights with decreasing inter-individual distance, resulting in a leaving of the
intruder. The results support the hypothesis that high frequency calls have a social function and
are directed towards an intruder to defend a food source.
16
11:00 Roosting ecology and behavior in nursery colonies of Rhinolophus hipposideros
R. Winter1, J. Mantilla-Contreras 1& S. Schmidt2
1
Institute of Biology and Chemistry, University of Hildesheim, Germany
Institute of Zoology, University of Veterinary Medicine Hannover Foundation, Germany
Corresponding author: [email protected]
2
Successful reproduction is a key factor for the preservation of endangered species. The loss of
roosts suitable for reproduction is a major threat for bats. Efficient roost protection, however,
presupposes a knowledge of roost requirements. We studied roosting ecology and behavior in
four nurseries of Rhinolophus hipposideros in abandoned man-made structures on Asinara
Island National Park. First we compared roosts with respect to microclimate, rate of mothers,
and onset of parturition. Secondly we analyzed perching behavior and roost usage in one of the
roosts. To avoid disturbances, roosts were monitored via cameras with infrared flash. Pictures
were automatically taken every 20 minutes from April to September 2015. Microclimatic
conditions inside roosts were measured with data loggers once per hour. To compare roosting
ecology across the four roosts we analyzed pictures of every third day throughout the whole
observation period. To characterize perching behavior and roost usage we analyzed the
pictures of each day from the end of May to the end of June. Perching behavior during daytime
was classified as individuals perching “isolated”, on “wing distance” and in “cluster”.
Additionally we investigated the inflight of adults and the return of mothers to their pups
during the night. Data were statistically validated using multiple regressions. The four roosts
were occupied by a maximum of 24, 9, 18 and 42 adults; however, bat numbers per roost
fluctuated from day to day. In the warmest roost, we recorded the earliest parturition and the
highest rate of mothers. The main factor for cluster formation before first parturition was
temperature, and after parturition it was the number of pups. An increase in temperature, or in
pups lead to less clustering. Returns of adults to the roost per night increased towards the onset
of parturition, and with the number of pups. The present data underline that R. hipposideros
relies on a network of roosts during the breeding season. Warmer roosts may promote the onset
of parturition and may therefore be preferred by mothers. Clustering may serve as an important
strategy of thermoregulation before parturition; after the onset of parturition, perching
“isolated” may prevent that pups drop to the ground. The present results are discussed with
respect to findings in central Europe.
17
11:15 Phonological syntax in babbling bouts of Saccopteryx bilineata pups
Ahana Fernandez, FU Berlin
Animal communication can range from simple, stereotypic calls to complex and variable
songs. Vocalizations can be composed of different syllable types which are arranged into
sequences. This arrangement of smaller units (usually defined as syllables) into larger
sequences (motifs or bouts) is defined as phonological syntax. Current analyses of
phonological syntax in animal communication focuses on vocalizations of adults, e.g. primate
alarm calls, whale song or bird song. Ontogenetic development of phonological syntax,
however, has not been studied so far. In our present study, we investigate whether babbling
bouts of Saccopteryx bilineata bat pups possess a syntactical structure and how it changes
throughout vocal ontogeny. This bat is a highly social species with a complex vocal repertoire
consisting of different call and song types. Pups learn at least one song type, the territorial
song, by imitating tutor songs during ontogeny. Vocal imitation is achieved by conspicuous
vocal practice in the form of babbling bouts, which bear a certain resemblance to the canonical
babbling of human infants and the plastic song of songbirds. We recorded the babbling bouts
of 31 pups belonging to 9 different colonies throughout their ontogeny (10-12 weeks from
birth to weaning). Isolation and echolocation calls are emitted immediately after birth and both
call types remain part of the species’ adult vocal repertoire. Starting about 13 -15 days of age,
pups of both sexes also produce syllables belonging to male adult territorial songs. Pup song
renditions become more stereotypic during ontogeny until they resemble adult territorial song
at approximately 10 weeks of age. Babbling bouts contain isolation calls, territorial song
renditions and other syllables from the entire adult vocal repertoire. A network analysis
revealed that isolation calls function as important nodes in the syntax network of babbling
bouts and facilitate the transition from one vocalization type to the next. Moreover, the
analysis suggests that the phonological syntax changes throughout ontogeny because older
pups produce babbling bouts with more different vocalization types than those of younger
pups.
18
11:30 Female influence on male courtship behaviour in the greater sac-winged bat,
Saccopteryx bilineata
Maria Eckenweber1, Franziska Harlacher1 & Mirjam Knörnschild2,3
1
Evolutionary Ecology and Conservation Genomics, University of Ulm, Germany
2
Animal Behaviour Lab, Institute for Biology, Free University Berlin, Germany
3
Smithsonian Tropical Research Institute, Balboa, Panama
Courtship behaviour signals the willingness to mate. It is often associated with an elaborated
display of males aiming at advertising fitness to females. In the greater sac-winged bat, males
try to persuade females with a multimodal and energetically costly display which includes
acoustic, visual and olfactory signals. However, only few studies have shown that also females
advertise willingness and ability (i.e. their fertile phase or oestrus) to mate. Here we provide
evidence that females of the greater sac-winged bat play a decisive role in the courtship. We
monitored eleven female S. bilineata from ten different colonies over the course of one mating
season. We recorded female vocalization and all behaviour patterns which were likely directed
towards males. Concerning vocalizations, we found a significant change in certain acoustic
parameters over the course of the mating season, as well as individual signature. We also
observed that females can influence male courtship behaviour by triggering male hover flights
through visual and acoustic signals. This interactive behaviour allows females to assess more
detailed information about quality and health of their harem male. The acoustic advertisement
of female’s oestrus is potentially an important signal for non-harem males to determine female
fertility, since they do not have access to chemical signals as harem males do.
11:45 Roosting interactions between con- and heterospecific maternity colonies
Zeus V 1, Puechmaille S J1 , Kerth G 1
1
University of Greifswald
Bats have been shown to coordinate their roosting behavior within the colony. However, it
remains largely unknown whether and to what extent different co-occurring colonies of con- and
heterospecifics influence each other when competing for the same roost types.
To address this issue, we studied five co-occurring colonies, belonging to three different species
of forest-dwelling bats. For the period of three maternity seasons, occupied bat boxes were daily
monitored with an automatic RFID-system to assess roosting behavior and interactions between
the colonies. Furthermore, we ran a simulation to test for each colony whether roosts were used
more often than expected if they had been recently occupied by a certain other colony.
We found a high flexibility in behavior from ignoring through attraction to avoidance. Thereby
bats differentiated between colonies of con- and different heterospecifics. To conclude, in a
shared habitat colonies of the same or different species can influence each other in their roosting
behavior.
19
Samstag (07. Januar 2017)
13:45 The evolution of male philopatry in proboscis bats – benefits and costs of a rare
mammalian trait
Linus Günther, Mirjam Knörnschild, Martina Nagy* and Frieder Mayer*
*joint senor authors
In contrast to the majority of mammals that predominantly exhibit male-biased dispersal,
Neotropical bats show an astonishing variability in dispersal behaviour. Currently, we know of
only a few bat examples with a reversed dispersal pattern where females leave their natal
group and males stay where they were born (e.g. in Rhynchonycteris naso, Saccopteryx
bilineata and Carollia perspicillata). While inbreeding avoidance is widely accepted as the
major driver for female dispersal, the evolution of male philopatry is still poorly understood
and discussed to be driven by male mating strategy, mate competition among male kin and kin
cooperation. During a five-year study we gathered detailed data on pedigree, individual
roosting and mating behaviour to assess the benefits and costs of male philopatry in proboscis
bats and improve the understanding of its evolution. Our behavioural data and genetic paternity
show that male proboscis bats adopt a territory based mating strategy with aspects of resourcedefence at night and direct female-defence during the day. Further, our results reveal that
social groups consist of several males descending from few patrilines and few unrelated male
immigrants. By assessing relatedness and competition (i.e. agonistic interactions, same mate
pairing and siring success during the same mating periods) of the present adult males we show,
that in R. naso closely related males face mate competition. However, these costs seem to be
outweighed by the benefits of philopatry, since philopatric males become more often territorial
and have a higher individual reproductive success compared to male immigrants. Finally, the
fact that males frequently tried to immigrate into colonies, but rarely stayed, reproduced or
became territorial indicates that male immigration is possible but assumingly difficult. This
illustrates how males may benefit from staying in their natal colony despite facing high mate
competition with their close relatives – a driver which is discussed to usually prevent male
philopatry in mammals.
20
14:00 Diversity and their evolution within the species-group of Myotis nattereri
Frieder Mayer1*, Elisabeth Hempel1, Emrah Coraman2, Christian Dietz3
Museum für Naturkunde Berlin, Germany
Institute of Environmental Sciences, Boğaziçi University, Turkey
3
Biologische Gutachten Dietz, Haigerloch, Germany
*
[email protected]
1
2
Natterer’s bats (Myotis nattereri) have a wide distribution range, which extends from Europe
to Northern Africa including the Caucasus Region. In the past, sequencing of fragments of the
mitochondrial genome (mtDNA) of Natterer’s bats especially in Western Europe revealed
several lineages that are quite divergent and in the range of interspecific differences. In our
current study we extend the analysis of genetic diversity to the east with a special focus on the
Caucasus. We limited our study not only to mtDNA but also sequenced three introns of the
nuclear genome (nucDNA).
The results support highly divergent lineages in the nuclear genome in addition to those in the
mitochondrial genome. Interestingly, divergence in mtDNA does not always match divergence
of nucDNA. This indicates introgression of mtDNA in the evolutionary history of populations
of Natterer’s bats. In the Caucasus region, the diversity is quite large for the given geographic
size of that region. This can be explained by its geographic location and its topography. To
which degree the divergent lineages may represent distinct biological species is difficult to
answer since contact zones have to be localized or may not exist.
14:15 Encounter-networks of bats revealed by miniaturized proximity sensors
Simon Ripperger* & Frieder Mayer*
*Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung
The observation of social behavior in free ranging bats is especially challenging because of
their nocturnal activity and their high mobility. Therefore, most work on interactions among
group living bats is based on data that has either been documented in captivity or focuses on
the behavior during day at the roosting site. Most technological solutions that would allow
tracking of group dynamics and social interactions outside the roost are only applicable to
larger sized animals. We developed a miniaturized and highly automated sensor network that is
designed to detect encounters among individual bats. The animal-borne sensors generate
dyadic datasets among tagged bats by direct encounter logging. Remote data download ensures
a minimal impact on the animals and a high degree of automation. This system opens new
avenues of research on bat (social) behavior, since its application is not limited to the roosts
but also documents individual interactions while foraging. We present the system design and
first “encounter-networks” for free ranging bats. Our work demonstrates that miniaturized
sensor nodes are valuable tools to create rich data sets for studying social behavior in small
vertebrates and in particular in bats.
21
14:30 Investigating food resource partitioning in time as a mechanism governing the
coexistence of two sister species of phyllostomid bats, Carollia perspicillata and Carollia
castanea
Tania Bosia and Sabine Schmidt
Institut für Zoologie, Stiftung Tierärztliche Hochschule Hannover
[email protected]
Species inhabiting the same area and possessing similar ecological requirements should differ
in at least one dimension to avoid competitive exclusion and coexist in sympatry. These
differences are particularly important to separate closely related species. Neotropical
phyllostomid bats have undergone an adaptive radiation in diet, ranging from insects, small
vertebrates, and blood, to nectar and fruits. Within frugivores, species of the subfamily
Carolliinae have been described to be Piper specialists. Bats of the genus Carollia are very
similar morphologically. Typically, two to three species differing slightly in size occur in
sympatry throughout their distribution range. So far, studies on resource partitioning between
these species have been mainly focussing on differences in spatial use of the habitat space or
food preference. Resource partitioning by differences in the timing of food consumption has
never been experimentally explored in frugivorous bats, although field observations suggest
different emergence times of the two sympatric sister species C. perspicillata and C. castanea.
We therefore investigated to which extent a temporal segregation might be responsible for their
coexistence. Bats tested were captured in the field, individually marked and kept in captivity for
the duration of the experiments, which were conducted in a flight cage during three hours
embracing the emergence time of the animals (17:30-20:30). Feeding behaviour and activity
pattern of a group of five C. perspicillata were observed alone as well as in the presence of four
conspecifics, or four C. castanea, to test for possible changes concerning the times of
investigation of the food source and of food-uptakes. We hypothesize that a variation in the
feeding behaviour and activity pattern of the larger species, C. perspicillata, is more likely to
occur in the presence of conspecific than in the presence of heterospecific food competitors. This
study will reveal whether a food resource partitioning in time might represent a mechanism
responsible for the coexistence of Carollia species.
22
14:45 Sex-specific age structure of Daubenton’s bats in summer sites: do males get
older?
Carola V. Behle1, Nina I. Becker12, Anna Roswag1, Jorge A. Encarnação12
1
Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus Liebig University Gießen
2
inatu.re, Institute for Applied Animal Ecology and Ecoinformatics
[email protected]; [email protected]; [email protected], [email protected]
The mechanisms of aging are still poorly understood and studies on longevity for males and
females of a species might give valuable new insights. Bat species have an exceptional life span
compared to other similar-sized mammals making them ideal model organisms for the study of
age structures. For wild mammals it is generally assumed that females get older than males. In
our study we assessed two factors concerning longevity: the maximal age of an individual and
the average age of a population. In our hypothesis we follow the general opinion, that
individually and averagely females should get older than males. As study organisms we chose
Daubenton’s bats (Myotis daubentonii) as males and females are philopatric over several years
which is a prerequisite for a mark-recapture study of ageing. For our study we used data from a
long-term study of four study areas near Gießen, Germany. Daubenton’s bats were captured by
mist-netting on their flight paths and individually marked by forearm banding. Contrary to our
expectations male bats reached a higher maximum (males: 14 years (13 – 16) (25 -75 percentile),
females: 9 years (9 – 13)) and even average (males: 4.3±0.7 years, females: 2.9±0.7 years) age
than females. One explanation might be the differing energetics of the sexes. While females have
a higher energetic demand especially during pregnancy and lactation and avoid torpor in those
times males can compensate for poor habitat quality or weather by extending their torpor use.
Another explanation might be an increased dispersal of younger males that would result in a
higher average and maximum age.
23
15:00 Decrypting cryptic diversity in the Hipposideros caffer complex in Ghana
Peter Vallo1,2, Heather J. Baldwin1,3, Petr Benda4,5, Christian Drosten6, Samuel K. Oppong7,
Adam J. Stow3, Marco Tschapka1,8
(1) Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Ulm, Germany
(2) Institute of Vertebrate Biology, Academy of Sicences of the Czech Republic, Brno, Czech Republic
(3) Department of Biological Sciences, Macquarie University, Sydney, Australia
(4) National Museum, Prague, Czech Republic
(5) Department of Zoology, Charles University, Prague, Czech Republic
(6) Institute of Virology, University of Bonn Medical Centre, Bonn, Germany
(7) Department of Wildlife and Range Management, Kwame Nkrumah University of Science and Technology,
Kumasi, Ghana
(8) Smithsonian Tropical Research Institute, Balboa, Panama
Sundevall's leaf-nosed bat, Hipposideros caffer (Sundevall, 1846), is a rather poorly
understood cryptic taxon, widespread throughout sub-Saharan Africa. Traditionally, Noack’s
leaf-nosed bat Hipposideros ruber (Noack, 1893) has been recognized as the sibling species of
H. caffer. Recent data show that H. tephrus Cabrera, 1906, from the Sudano-Sahelian zone can
be regarded as distinct from the Southern African H. caffer s.str. In a study of the H. caffer
complex in Ghana, 383 individuals were sequenced on a 782 bp fragment of the mitochondrial
cytochrome b gene. All four main phylogenetic lineages known to occur in West Africa were
present, suggesting existence of four cryptic species in Ghana. Three of them, conforming to
H. ruber by size, occurred in sympatry in central Ghana. The fourth one, pertaining to H.
tephrus, was found in the wet forest zone of the west coastal region. Of the three H. ruber
lineages, one remains exclusively West African, while the other two are related to genetic
forms from Central and East Africa. Genetic differences within the Ghanaian H. caffer
complex were further investigated using a panel of ten microsatellites. Four separate groups
could be identified that corroborate the division into mitochondrial lineages corresponding to
H. tephrus and three cryptic H. ruber species. External morphometric and acoustic data
support the genetic differentiation within the H. caffer complex and enhance its taxonomic
resolution.
24
15:45 Habitat use of pteropodid bats and their importance as seed dispersers, compared
to birds, on the slopes of Mt. Kilimanjaro, Tanzania
AV Vogeler1, M Vollstädt2, K Böhning-Gaese2,4, M Tschapka1,3
1
University of Ulm, Institute of Evolutionary Ecology and Conservation Genomics, 89069 Ulm
Biodiversity and Climate Research Centre (BiK-F) and Senckenberg Gesellschaft für Naturforschung, 60325
Frankfurt am Main
3
Smithsonian Tropical Research Institute, Balboa, Panamá
4
Johann Wolfgang Goethe University of Frankfurt, Department of Biological Sciences, 60438 Frankfurt am Main
2
Anna Vogeler, University of Ulm, Institute of Evolutionary Ecology and Conservation
Genomics, 89069 Ulm, email: [email protected]
Although frugivorous birds and bats are known to be important mutualists for plants, little
information is available on their function as seed dispersers in Africa including on how landuse changes may affect the associated ecosystem services. An interaction between resource and
consumer species requires trait matching and therefore species morphology is an important trait
set indicating the respective functional roles. We assembled interaction networks of bats and
birds with their food plants and assessed a species’ functional role based on the traits of its
interaction partners in a multidimensional trait space. We analyzed fecal samples of six
pteropodid bat species (1420 Individuals; Eidolon helvum, Epomophorus minimus,
Epomophorus wahlbergi, Rousettus aegyptiacus, Rousettus lanosus, and Lissonycteris
angolensis) captured in seven different habitat types (Maize, Savanna, Savanna Riparian
Stripes, Homegarden, Coffee plantation, Lower Mountain Forest, Forest Riparian Stripes).
Food plants are identified using morphological characteristics of seeds and additionally we are
currently evaluating the use of DNA barcoding techniques.
Preliminary analyses show distinct differences in community composition in the different
habitat types, showing that human land use and potentially also climate change impact these
keystone species. We further found changes of specialization in the seed dispersal network,
such as a decrease with increasing mean annual temperature and intensified land use. Moreover,
morphological differences between vertebrates reflected their functional differences. In most
fecal samples Ficus spp. (Moraceae) seeds were found, which emphasizes figs as crucial food
plants whose seeds are distributed by the various bat species to different habitats.
Our study stresses the importance of fruit bats compared to birds as seed dispersers on Mt.
Kilimanjaro, particularly for the Moraceae family. The high degree of mobility in combination
with seed retention times of more than 12 hours suggests a high potential for long-distance
seed dispersal and the potential to link different habitat types. Therefore, changes in
community composition caused by habitat degradation may have negative consequences on
overall seed dispersal and forest regeneration functions. Pending topics of our project are the
assessment of the ecomorphological traits of plants and bats, followed by a mutualistic network
analysis.
25
16:00 Should I stay or should I go? Site fidelity of Daubenton's bats over several years
Jennifer Pöll1, Nina I. Becker12, Jorge A. Encarnação12
1Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus Liebig University Gießen
2inatu.re, Institute for Applied Animal Ecology and Ecoinformatics
[email protected]; [email protected]; [email protected]
Philopatry is common in many species even over long time periods. In mammals females tend
to be more philopatric than males and in most species juvenile males are more likely to
disperse than adult ones. We studied philopatry in Myotis daubentonii (Daubenton's bats) as it
is a very long-lived species and both sexes regularly return to their summer sites. As generally
suggested for mammals we hypothesized that adult females are more philopatric than adult
males, as they form stable nursery colonies in successive years. Furthermore, male juveniles
should disperse more often than female juveniles. For this purpose we studied site fidelity of
M. daubentonii at four locations. My results revealed that the dispersal of juveniles is not sexbased but that adult males show a lower site fidelity than adult females. However, for both
adult sexes philopatry seems to be site specific possibly caused by resource availability e.g.
food or mates.
26
16:15 The costs of leaving early: Mortality costs associated with departure from the
hibernaculum in bats
CHRISTINE REUSCH1,*, ALEXANDER SCHEUERLEIN2, LENA GROSCHE1,3, FRAUKE
MEIER1,3, JUTTA GAMPE2, GERALD KERTH1
*
presenting author
University of Greifswald, Zoological Institute and Museum, Johann-Sebastian-Bach-Str. 11-12,
17489 Greifswald, Germany
2
Max Planck Institute for Demographic Research (MPIDR), Konrad-Zuse-Straße 1, 18057
Rostock, Germany
3
Echolot – Büro für Fledermauskunde Landschaftsökologie und Umweltbildung, Eulerstr. 12,
48155 Münster, Germany
1
It is well documented that hibernation is crucial for temperate bat species to survive periods with
low food availability during the winter. However, how differences in individual hibernation
behaviour influences mortality and whether individuals are plastic with respect to their
hibernation behaviour are largely unknown. Because bats are of high conservation concern it is
of prime importance to understand factors that might influence mortality during hibernation.
In this study we used an individual based data-set of the two bat species Myotis nattereri and
Myotis daubentonii at a hibernaculum. Each PIT-tagged individual was automatically recorded
while passing the entrances and, therefore, can be followed at the hibernaculum over its life time.
We investigated the impact of their individual hibernation behaviour, precisely the timing of
departure in late winter and early spring, on mortality, as well as differences within and between
the two species from 2011 until 2015.
Our results suggest considerable differences among individuals within as well as between bat
species with respect to emergence behaviour from the hibernaculum. Hence, our study highlights
the necessity to further investigate the phenotypic plasticity of hibernation behaviour and to
understand its effects on the demography of bats. We conclude that it is important for the
conservation management of bat species to identify key factors for the survival of individuals
during hibernation and to distinguish between species to select the best management tools for
bat hibernacula.
27
16:30 Radarbasierte Detektion von Fledermäusen bei Windenergieanlagen
Dr.-Ing. Jochen Moll
Der Energiegewinnung aus Windkraft kommt in Deutschland eine herausragende Bedeutung zu.
Allerdings haben Windenergieanlagen (WEA) einen Einfluss auf die Tierwelt. Insbesondere
Fledermäuse werden in ihrem Lebensraum beeinträchtigt, was zu einer hohen Sterblichkeit der
Tiere führt. Zu den primären Todesursachen zählen dabei die unmittelbare Kollision der
Fledermäuse mit den Rotorblättern, als auch eine Barotrauma Schädigung durch einen starken
Druckabfall beim Durchflug der Tiere durch die Rotorblattebene.
Im Rahmen des Forschungsprojektes B²-Monitor (www.b2monitor.de) wird ein Radarsensor
entwickelt, um die Aktivität von Fledermäusen in der Nähe von WEA großflächig zu erfassen.
Der Radarsensor wird dabei am Turm der WEA dauerhaft installiert. Daraus leitet sich ein
adaptives Steuerungskonzept der Anlage ab, welches die Sterblichkeit von Fledermäusen
reduziert und gleichzeitig die Betriebszeiten der Anlage für maximalen Stromertrag optimiert.
Dieses Konzept trägt dazu bei, die Interessen der WEA-Betreiber und Umweltverbände zu
harmonisieren, den gesetzlichen Auflagen bei der Inbetriebnahme von WEA hinsichtlich dem
Vorkommen von Fledermäusen gerecht zu werden und eine höhere gesellschaftliche Akzeptanz
von WEA zu erzielen.
Im Rahmen des Vortrages wird das Monitoring-Konzept vorgestellt, Ergebnisse der
radarbasierten Fledermausdetektion diskutiert und Ultraschallmessungen vorgestellt.
Neben der Goethe-Universität Frankfurt sind im B²-Monitor-Projekt die Firmen Wölfel
Engineering GmbH + Co. KG (Höchberg), HF Systems Engineering GmbH & Co. KG (Kassel)
und VOLTA Windkraft GmbH (Ochsenfurt) beteiligt. Gemeinsame Untersuchungen im
Fledermauslabor wurden mit Prof. Kössl, M. Jerome Beetz und Dr. Julio Hechavarria
durchgeführt.
Danksagung: Das Forschungsvorhaben wird durch das Bundesministerium für Wirtschaft und
Energie gefördert (FKZ 0325791A).
28
16:45 Challenges of acoustic monitoring of bats - a biosonar perspective
Jens C. Koblitz1, Peter Stilz2,
1
Bioacoustics Network, Neuss, Germany
Bioacoustics Network, Hechingen, Germany
2
Acoustic monitoring of bats is increasingly used in biodiversity assessments, population
monitoring and environmental impact assessments. Besides accurate species identification,
additional factors make it challenging to derive population trends, yet - sizes based on acoustic
monitoring. Inter- and intra-species- as well as individual variation of acoustic parameters and
acoustic activity result in varying detection probability. Changes in environmental conditions
result in a large changes in the volume monitored by the device. Differences in the devices
used for acoustic monitoring make it inherently difficult to compare data collected with
different devices. By broadcasting bat echolocation calls from various distances to monitoring
devices, the acoustic parameters influencing the successful detection of a call were examined.
A microphone array was used to track bats in the vicinity of monitoring devices and the
distance between device and bat was measured for each call based on the time of arrival
difference. The acoustic detection function, the probability of detecting calls as a function of
distance, was then derived for multiple detector types.
17:00 Of bots and bats: A compact automated video surveillance system for studying
bats in the field.
Patrick Cvecko1, 2, Rachel A. Page2, Marco Tschapka1, 2
1Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Alee
11, D-89069 Ulm, Germany
2Smithsonian Tropical Research Institute, Apartado 0843 - 03092, Balboa Ancón, República de Panamá
Field-based observations on bats can be difficult due to their nocturnal and cryptic lifestyle.
Documenting bats via infrared (IR) video recordings has become an important tool in
behavioral studies of bats. However, most commercially available IR camera systems are
expensive and / or rather limited in their adjustability to the specific needs of bat ecologists.
We are developing a compact IR video recording system, with interchangeable lenses and
internal IR-LEDs, that uses a single-board computer and camera module developed by the
Raspberry Pi foundation (UK). This remotely controlled camera system is capable of, e.g.,
continuous video recordings of more than 24 hours, or may also take pictures automatically in
predefined intervals of up to one week.
We tested eight of these waterproof camera systems during six month in a neotropical lowland
rain forest in Panama (Barro Colorado Island). We monitored bats in various roost types from
leaf tents to tree cavities, and captured, e.g., rarely observed footage on leaf modification by
Thomas's fruit-eating bat Dermanura watsoni that got abruptly cut short by a predation event
from a Spectacled owl (Pulsatrix perspicillata).
All parts used for our camera system are inexpensive and easily available. There is a growing
Open Source community using and developing this technology and providing support on all
kinds of projects. Therefore, we encourage bat researchers, to take advantage of this highly
dynamic development and to build own camera systems that are tailored to suit the own
specific projects.
29
17:15 Forschung - Umweltbildung - Naturschutz: Mit FUN in die Wildnis
Michael Gerhard Schöner1, Ralf Koch2 & Gerald Kerth1
1
Applied Zoology and Nature Conservation, Zoological Institute and Museun, University of Greifswald
2
Naturpark Nossentiner/Schwinzer Heide, Plau am See
In large parts of public opinion academic sciences and nature conservation are still subject to
scepticism. One possible solution to this reluctance is to offer people the possibility to
participate in scientific research. This is why we funded the new citizen science project FUN,
(funded by the Deutsche Bundesstiftung Umwelt), which will start in March 2017. Using wildranging bats as model system FUN combines some of the most fundamental factors to
successfully integrate citizens in research and applied conservation: academic experience with
novel perspectives and ideas of the citizen scientists, field research with computer-based data
analyses, public education for nature conservation with academic and school teaching and
people of different ages and backgrounds. During the project several bat species are regularly
monitored in their hibernacula, colony day roosts, and hunting areas within the nature park
Nossentiner/Schwinzer Heide (Mecklenburg-Pomerania). Using PIT-tags, batcorders and
infrared-video the automatically gained raw data are uploaded to an interactive website and
become available for the interested public and schools. To guarantee for a high quality of the
results each raw data set needs to be analysed by different participants and will then be
evaluated by an expert before being further processed for publication in scientific journals. By
including didactics, students and schools we will bring wilderness into classrooms and ensure
that developed teaching materials are tested and disseminated. Our overall aim is to make
science more accessible for the public. We are convinced that FUN will promote a new
generation of scientists within and outside academia and contribute to the conservation of
nature and bats, following the guiding principle: You only protect what fascinates you.
30
17:30 Zur Praxis der Konfliktbewertung in Fledermausfachgutachten zu WEAs im
BImschG-Verfahren.
Kiefer, A.1, Trenz, M.1, Lüttmann, J.2, Veith, M.1
1
2
Biogeographie, Universität Trier, Universitätsring 15, 54286 Trier
FÖA Landschaftsplanung GmbH, Auf der Redoute 12, 54296 Trier
Fledermausfachgutachten, erstellt im Rahmen des immissionsschutzrechtlichen
Genehmigungsverfahrens eines Windkraftprojekts, sollen sicherstellen, dass der Schutz von
Fledermäusen hierbei hinreichend berücksichtigt wird. Hierzu müssen die damit beauftragten
Planungsbüros ihre Erfassungsbefunde im Kontext einer eingriffsbezogenen Konfliktanalyse
bewerten.
An 30 Fledermausfachgutachten aus Rheinland-Pfalz untersuchten wir, in welchem Umfang
eine solche Konfliktbewertung tatsächlich erfolgte, ob es eine Beziehung zwischen der Größe
eines nachgewiesenen Fledermausbestandes und der Stärke des erkannten Konflikts gibt, und
welche Maßnahmen zur Vermeidung des Konflikts vorgeschlagen wurden. Hierzu werteten
wir die Daten zu fünf Federmausarten aus: Pipistrellus pipistrellus, Pipistrellus nathusii,
Nyctalus noctula, Nyctalus leisleri und Myotis bechsteinii.
Die Konfliktbewertung erfolgt in den meisten Gutachten nicht anlagen- sondern
projektbezogen. In einigen Fällen werden unzulässiger Weise Artengruppen bewertet. Das
Methodenspektrum zur Konfliktermittlung war oft sehr begrenzt (meist bioakustisch, kaum
Radiotelemetrie trotz häufiger Netzfänge, die als Hinweis auf Wochenstubenquartiere im
Wirkraum der WEA hätten gewertet werden können). Häufig wurde gar keine explizite
Konfliktwertung durchgeführt, und wenn dann oft pauschal (Literaturangaben, „copy-paste“Bewertung). Es war keine Beziehung zwischen der Konfliktstärke und der Eingriffsbewertung
erkennbar. Ein „Standardset“ an Empfehlungen dient der Konfliktabwendung beim Betrieb der
WEA (inb. Abschaltalgorithmus, ggf. in Verbindung mit einem Monitoring, d.h.
Schlagopfersuche und akustisches Gondelmonitoring). Einschränkungen in der Errichtung der
untersuchten WEAs als Konsequenz der Konfliktbeurteilung kommen faktisch nicht vor.
Insgesamt legen unsere Ergebnisse nahe, dass es dringend einer Orientierungshilfe (am besten
Richtlinie) zur Konfliktbewertung bedarf. Gutachten ohne hinreichende und fundierte
Konfliktbewertung sollten von den Genehmigungsbehörden unter Hinweis auf die Mängel als
nicht prüffähig zurückgewiesen werden. Hierzu jedoch müssen die Behörden personell und
fachlich in die Lage versetzt werden.
31
17:45 Up and down: Mopsfledermäuse erkunden aktiv Gittermasten – Implikationen
für WEAs
Veith, M.1, Budenz, T.2,3, Gessner, B.2, Lüttmann, J.4, Molitor, F.4, Servatius, K.4
1
Biogeographie, Universität Trier, Universitätsring 15, 54286 Trier
Gessner Landschaftsökologie, Im Ermesgraben 3, 54338 Schweich
3
aktuelle Adresse: Am Schlaufenglan 67, 66606 Sankt Wendel
4
FÖA Landschaftsplanung GmbH, Auf der Redoute 12, 54296 Trier
2
Fledermäuse gehören zu den durch Windkraftanlagen (WEAs) stark bedrohten Tierarten.
Mehrere Hypothesen versuchen zu erklären, warum Fledermäuse an WEA tödlich
verunglücken. Vielen gemeinsam ist, dass sie implizit annehmen, dass Fledermäuse die WEAs
erkunden und hierdurch in den Wirkbereich der Rotorblätter kommen.
An zwei Gittermasten an Waldstandorten in Rheinland-Pfalz (Höhe des Kronendachs jeweils
20-25 m) überprüften wir die Hypothese, dass Mopsfledermäuse gezielt an den Masten auf und
ab fliegen: Beuren (weitgehend geschlossenes Kronendach um den Mast) und Schöndorf
(offenes Kronendach). An den Masten waren batcorder in unterschiedlichen Höhen
angebracht: 3,5 m (Boden), 20 m (Baumkronen), 35 m (über dem Kronendach) sowie 50 und
80 m (freier Luftraum). Unter der Annahme vertikaler Flugbewegungen erwarteten wir zeitlich
korrelierte Registrierungen an jeweils benachbarten batcordern.
Die vertikale Verteilung der Registrierungen an den beiden Standorten war sehr
unterschiedlich. Kontakte der Mopsfledermaus im freien Luftraum wurden ausschließlich in
Beuren dokumentiert 3-mal auf 50 m), obwohl die Boden- und Kronenaktivität an beiden
Standorten hoch war. Signifikante Auf- und Abwärtsbewegungen zw. 3,5 und 20 m waren an
beiden Standorten nachweisebar, solche zwischen 20 und 35 m nur in Beuren, dem Standort
mit geschlossenem Waldbestand. Unsere Daten belegen, dass die Mopsfledermaus aktiv an
den Masten auf- und abfliegt. Letzteres interpretieren wir als Erkundungsverhalten. Die
geringe Aktivität im freien Luftraum über dem Kronendach passt zur Jagdstrategie und
Echoortungs-Physiologie der Art, die einen „Echohintergrund“ benötigt.
Eine maßgebliche Gefährdung der Mopsfledermaus durch Kollision mit den Rotorblättern oder
Barotrauma im freien Luftraum hoch über dem Kronendach ist angesichts der beobachteten
sehr geringen Nutzung dieses Stratums unwahrscheinlich. Allerdings können wir nicht
ausschließen, dass Erkundungsflüge an den Masten aufwärts gelegentlich Individuen in den
Wirkbereich der Rotorblätter bringen (anlagenbedingter Effekt).
32
Sonntag (08. Januar 2017)
08:45 Landscape feature and scale dependent spatial niches for bats foraging above
intensively used arable fields
Olga Heima,b,*, Lukas Lorenzb, Stephanie Kramer-Schadta, Kirsten Jungc, Christian C. Voigta,d,
Jana Eccardb
Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, D – 10315 Berlin, Germany
Animal Ecology, Institute of Biochemistry and Biology, University of Potsdam, Maulbeerallee 2a, D – 14469
Potsdam, Germany
c
Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert- Einstein-Allee 11, D
– 89069 Ulm, Germany
d
Department of Animal Behaviour, Freie Universität Berlin, Takustr. 3, D – 14195 Berlin, Germany
a
b
Many bat species are threatened by current anthropogenic land-use changes due to agricultural
management and its intensification. Thus, detailed knowledge on how bats use agricultural
landscapes is crucial for the conservation of this threatened taxon. Our aim was to identify spatiotemporal factors and interactions which are relevant for the activity of bats above conventionally
managed arable fields in Germany. We repeatedly monitored the relative activity of bats above
open arable fields using acoustic monitoring. In addition, we assessed site related biotic and
abiotic factors and analyzed selected landscape characteristics across five spatial scales. Finally,
we used these variables and their combinations to identify those factors which explained bat
activity best. The relative activity of bats was most often related to a combination of local and
landscape effects. Hereby, the proportion of water cover in the area adjacent to arable fields was
always associated with a higher bat activity. Landscape characteristics influenced the
relationship between relative bat activity and insect abundance. Furthermore, specific landscape
elements were more important for the relative activity of some bat species during summer
compared to autumn. Bat species differed in the specific landscape features which were most
relevant for their activity. This may point towards the possibility of resource partitioning on the
level of habitat, diet and spatial scales. Based on our results, landscape characteristics
surrounding conventionally managed arable fields affected bat activity and influenced the way
bat species interacted with insects above arable fields. Therefore, the predicted increase in landuse intensity and farmland expansion might have negative effects on bat activity above farmland
and further reduce the interaction of bat species with the agro-ecosystem.
33
09:00 Bat flies (Diptera: Streblidae) in a fragmented habitat in Panama.
Thomas Hiller1,2, Stefan D. Brändel1,2, Rachel Page2, Marco Tschapka1,2
1
Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
2
Smithsonian Tropical Research Institute, Balboa, Panama City, Panama
Habitat loss and fragmentation influence the survival of many species, especially in the highly
diverse tropical biomes. Recent studies on bats showed that successful persistence in degraded
habitats depends on the degree of specialization: whereas generalist may even profit of habitat
alterations, specialist species may go locally extinct. For obligate bat ectoparasites such as the
highly species-specific bat flies (Diptera: Streblidae), the body of their host species represents
their habitat. Changes in bat species composition and abundance will therefore directly
influence the local species richness of the streblid ectoparasites and may also affect prevalence
and intensity of parasitism.
Between 2013 and 2015 we captured bats in 3 habitat types with different human influence
(closed forest, fragments surrounded by water, fragments surrounded by agriculture) in
Panama and collected from the six most common bat species (n=4444) a total of 3524 bat flies,
belonging to 11 species. Prevalence per species ranged from 8.0% to 67.9% and mean intensity
of parasitism was between 1.1 and 2.8 flies per infested bat. Preliminary analyses show
significant differences in prevalence and intensity of parasitism between bat host species,
between habitat types as well as in age and sex within the host species.
Further analyses will target the high variability between host species as well as identify the
habitat and host characteristics mostly affecting parasitism by bat flies and thus shed light on
the complex host-parasite interactions.
34
09:15 Habitat disturbance results in chronic stress and impaired health status, but not
increased viral shedding in forest-dwelling paleotropical bats
Anne Seltmann1,2, Gábor Á. Czirják3, Victor Corman4, Christian Drosten4, Henry Bernard5,
Matthew Struebig6, Christian C. Voigt1,2
1
Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17,
10315 Berlin, Germany, fax: +49-30-5126-104. telephone number: +49 30 5168 326. Email: [email protected], [email protected]
2
Institute of Biology, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
3
Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17,
10315 Berlin, Germany
4
Institute of Virology, University of Bonn Medical Centre, Sigmund-Freud-Str. 25, 53127 Bonn, Germany
5
Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu,
Sabah, Malaysia
6
Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of
Kent, Canterbury, Kent, CT2 7NR, UK
Emerging infectious diseases (EIDs) are considered as a major threat to human health
worldwide. Most of the EIDs seem to result from an increased contact between wildlife and
humans, especially when humans encroach into formerly pristine habitats. Yet, habitat
deterioration may negatively affect the physiology and health of wildlife species, for example
by stress-related immune suppression, which may eventually lead to a higher susceptibility to
infectious agents and/or increased shedding of the pathogens causing EIDs. Here, we tested in
a paleotropical forest with ongoing logging and fragmentation whether habitat disturbance
influences the body mass, immunity and occurrence of astro- and coronaviruses in eight
species of bats, a taxon implicated as a major reservoir for highly virulent viruses. We
measured and compared body mass, chronic stress (indicated by neutrophil to lymphocyte
ratios) and the number of circulating immune cells between bats with different roost types
living in recovering areas, actively logged forests, and fragmented forests in Sabah, Malaysia.
In a cave-roosting species, chronic stress levels were higher in individuals from fragmented
forests compared with conspecific from actively logged areas. Small, foliage-roosting species
showed a reduced body mass and decrease in total white blood cell counts in actively logged
and fragmented forests compared with conspecifics living in recovering areas. In contrast to
our hypothesis, anthropogenic habitat disturbance was not associated with higher corona- and
astroviral detection rates in fecal samples. However, we found a higher detection rate of
astroviruses at the beginning of the rainy compared to the dry season and a trend that
individuals with a poor body condition had a higher probability of shedding astroviruses in
their feces. By identifying the beginning of the rainy season as a risk factor for increased viral
shedding that may potentially result in increased interspecies transmission, we contribute to
means of preventing viral spillovers from bats and other wildlife reservoirs to humans.
35
09:30 Do European bats suffer from the White-Nose Disease caused by
Pseudogymnoascus destructans?
MARCUS FRITZE1,2, CHRISTIAN C. VOIGT2, GABOR A. CZIRJAK2 & SEBASTIEN J.
PUECHMAILLE1,3
1
Zoology Institute,University of Greifswald,Soldmann-Str. 14, D - 17487 Greifswald, Germany
Leibniz institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
3
School of Biology and Environmental Sciences, University College Dublin, Belfield, D4 Dublin Ireland
2
The cold-loving fungus Pseudogymnoascus destructans (Pd) colonizes bats during hibernation.
The fungus affects the snouts and all the hairless skin membranes of the bats and causes
lesions, which via cascading processes, leads to mass mortalities resulting in regional
extinctions in some North America bat species. The epidemic that was first discovered in 2006
near New York, spread rapidly across the east coast of North America and very recently
reached the west coast. In Europe, and probably in the whole Eurasian temperate zone, this
fungal species seems to be common in bat hibernacula but with no evidence of associated bat
mortalities. We investigated the presence of Pd via visual observations, bat swabbing as well
as environmental DNA and related the fungus presence with bat mortality and environmental
conditions within the hibernation sites. Temperatures around 8 °C and a high relative humidity
within the hibernacula are associated with the presence of Pd in the hibernation sites across
Europe. Occasional fatalities but no mass mortalities were recorded within the sites. Our
results present for the first time baseline mortality in European bat hibernacula.
Pseudogymnascus destructans was not detected as a predictor for mortality. Physiological data
and blood samples from infected and non-infected European bats were compared in an
immunological analysis to better understand if European bats suffer from white-nose disease
and if they developed immunological resistance or tolerance. Integrating our ecological and
immunological results in an evolutionary framework brings novel insights into mechanisms of
resistance/tolerance against fungal diseases in European bats.
36
Poster
Was beeinflusst die Erfüllung methodischen Vorgaben zu WEAs im BImschGVerfahren?
Gebhard, F.1,2, Kiefer, A.1, Kötteritzsch, A.1,3, Lüttmann, J.4, Hendler, R.5, Veith, M.1
1
Biogeographie, Universität Trier, Universitätsring 15, 54286 Trier
Gessner Landschaftsökologie, Im Ermesgraben 3, 54338 Schweich
3
Büro für Faunistik und Landschaftsökologie, Gustav-Stresemann-Str. 8, 55411 Bingen;
4
FÖA Landschaftsplanung GmbH, Auf der Redoute 12, 54296 Trier
5
Institut für Umwelt- und Technikrecht (IUTR), Universität Trier, Universitätsring 15, 54296 Trier
2
Um den Schutz von Fledermäusen während der Planungsphase eines Windkraftprojekts zu
berücksichtigen, werden im Rahmen des immissionsschutzrechtlichen
Genehmigungsverfahrens Fledermaus-Fachgutachten verfasst. In mehreren Bundesländern
existieren hierzu methodische Arbeitshilfen.
An 156 Fledermausfachgutachten aus sechs Bundesländern untersuchten wir mittels einer
Varianzanalyse die Erfüllung methodischer Mindeststandards sowohl des Gesamtgutachtens
als auch der Teilaspekte Untersuchungsrahmen, Erfassungsmethoden, Konfliktbewertung,
Ergebnisdarstellung und Verbotstatbestände. Wir testeten den Einfluss folgender Faktoren auf
diese Qualitätskriterien: Vorhandensein einer landesspezifischen Arbeitshilfe, das
Erstellungsjahr, das Bundesland, der Auftraggeber und das ausführende Planungsbüro.
Die Gutachten variieren teils stark im Grad der Erfüllung methodischer Standards, sowohl in
der Gesamtqualität als auch in Bezug auf die Einzelkriterien. Durchschnittlich wurden 78 %
(Spannweite 19 bis 96 %) aller methodischen Vorgaben erfüllt, allerdings gab es signifikante
Unterschiede zwischen den Bundesländern. Insbesondere der kritische Bereich der
Konfliktbewertung wurde unterschiedlich erfüllt. Ein positiver Effekt der Arbeitshilfen auf die
Qualität der Fachgutachten war feststellbar, jedoch kann eine Qualitätssteigerung zwischen
2005 und 2013 nicht belegt werden. Während ein Einfluss des Auftraggebers auf die Qualität
der Gutachten kaum feststellbar war, zeigten sich signifikante Unterschiede bei den
ausführenden Planungsbüros in der Gesamtqualität sowie in den meisten Teilkriterien. Hieraus
leiten wir einen dringenden Handlungsbedarf hinsichtlich der Standardisierung der
methodischen Vorgaben sowie der Qualitätskontrolle und -sicherung von FledermausFachgutachten ab.
37
Influence of habitat use on hind leg morphology of bat flies (Diptera: Streblidae) in
Panama
Benjamin Honner1, Thomas Hiller1,2, Stefan Brändel1,2, Rachel Page2, Marco Tschapka1,2
1
Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
2
Smithsonian Tropical Research Institute, Balboa Ancón, Republic of Panama
Bat flies are obligate ectoparasites of bats, feeding on the blood of their host. Most bat flies
exhibit high host specificity and parasitize a single bat species. On their hosts bat flies prefer
particular habitats, enabling them to escape from mechanical defense mechanisms such as
grooming and to prevent competition with other hematophagous bat fly species parasitizing the
same host.
Based on their preferred habitat on the bats, bat flies can be categorized into three ecotypes: „fur
runner“ (on the fur), „fur swimmer“ (in the fur) and „wing crawler“ (on wing membranes) (ter
Hofstede et al., 2004). The pronounced differences in the surface of these different habitats might
have selected for different morphological adaptations in the bat fly ecotypes. Therefore, we
focused on the hind leg morphology of 19 bat fly species parasitizing eleven bat species from
Panama and expected these structures to be adapted for locomotion in the different habitats
available on bats. We photographed hind legs of bad flies and measured these using the software
Image J. We determined the percentage of trochanter-femur length, of tibia length and of tarsal
length relative to the total hind leg length as well as the percentage of femur width relative to
the trochanter-femur length was measured. These morphological data were analyzed using
NMDS and were tested for morphological differences between the three ecotypes. We found
that the three ecotypes of bat flies differed significantly from each other – and even discovered
a fourth type differing significantly from all others. In conclusion, our study showed distinct
specializations of the hind legs of bat flies using different body parts of bats as their habitats and
suggests that there might be even more, yet undescribed habitat niches for bat flies available on
bats.
38
Ion channels for fast temporal processing in the brainstem auditory pathway of
echolocating bats
Marianne Vater, Alina Baasner, Tina Saborowski
Institut für Biochemie & Biologie - Allgemeine Zoologie, Universität Potsdam,
Karl Liebknecht Str. 26, 14476 Potsdam
Fast and precise temporal processing by auditory brainstem neurons of mammals depends on
their morphology, synaptic properties and differential expression profiles of certain ion
channels. HCN channels (hyperpolarization-activated cyclic nucleotide gated channel) are
known to crucially contribute to fast neuronal integration in several monaural and binaural
nuclei, and voltage-gated potassium channels of the Kv1 family influence the threshold, shape,
duration and timing of action potentials (review: Golding & Oertel 2012 J Physiol
590.22:5563-5569).
This study investigates the neuronal distribution of HCN1 channels and Kv1.1 channels in the
auditory brainstem of the short-tailed fruit bat Carollia perspicillata with
immunohistochemical techniques. Since precise temporal processing of acoustic signals is
especially important for echolocation we were interested to define similarities and differences
in the expression patterns found in the bat with those reported for non-echolocating mammals.
There were profound similarities in HCN1 expression patterns to nonecholocating mammals in
that octopus cells of the cochlear nucleus, principal neurons of the lateral and medial superior
olive, and a subpopulation of inferior colliculus neurons expressed high levels of HCN1,
whereas neurons of the dorsal cochlear nucleus, the medial nucleus of the trapezoid body and
dorsal nucleus of the lateral lemniscus lacked HCN1-expression. A profound difference is the
lack of HCN1 in spherical cells of the cochlear nucleus and throughout most of the ventral
nucleus of the lateral lemniscus in the bat.
All cell types known to express Kv1.1 and to respond with high temporal precision in other
species were labeled in the fruit bat, emphasizing basic functional similarities. Additionally,
we describe a differential distribution of Kv1.1 in subpopulations of inferior colliculus neurons
indicating the presence of functionally distinct cell populations and differential temporal
processing properties across frequency channels.
39
Echolocation behavior of the fish eating bat, Myotis pilosus
Christina Weiss1, Hans-Ulrich Schnitzler1, Vu Dinh Thong2, Annette Denzinger1
1
Tierphysiologie, Institut für Neurobiologie, Universität Tübingen
Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, Hanoi, Vietnam
2
Myotis pilosus is distributed in China, Hong Kong, Laos and Viet Nam. It belongs to the guild
of edge space trawling foragers and feeds on fish and insects. Except fot the description of
single calls nothing has been known sofar about the echolocation behavior of M. pilosus. We
found M. pilosus hunting above a lake in Cat Ba, Vietnam, which is the first record of M.
pilosus on the island, and recorded the echolocation and foraging behavior. M. pilosus flew
mainly low above the water surface taking prey items out of the water or from the water
surface, but we also observed high catches of insects. In search flight, M. pilosus emitted
echolocation calls typical for Myotis species, consisting of a steeply modulated component
followed by a more shallowly modulated part and a further steeply modulated component.
Duration varied between 4 and 12 ms, bandwidth and start frequency correlated with pulse
duration. Around 6 ms the signals had a mean start frequency of 61 kHz and a mean end
frequency of 28 kHz resulting in a mean bandwidth of 33 kHz. The distribution of pulse
intervals had a first peak arround 70 ms, suggesting that M. pilosus emits 2 signals per wing
beat. In contrast to other Myotis species that have uniform search signals M. pilosus emitted
search signals varying in an irregular pattern between longer pulses with smaller bandwidth
and shorter pulses with higher initial frequency and therefore larger bandwidth. The longer and
shorter search calls often also varied in their sound pressure level at the microphone suggesting
that they were emitted into different directions. Approach signals were grouped and the
terminal group always consisted of buzz I and buzz II. The mean number of calls was 15,8 ±
2,0 in buzz I and 7,7 ± 3,1 in buzz II. Buzz II was almost always followed by a search signal
longer than 6 ms. We will discuss the possible function of the varaiation between longer and
shorter search signals not observed in other trawling Myotis species.
40
Frequency integration during distress call processing by auditory cortex neurons of
Carollia perspicillata
Mahyar Moghimi, Jan Pastyrik, Julio Hechavarria
The auditory system has to extract information from complex stimuli of the real natural world
such as vocalizations produced by conspecifics that cover a wide frequency spectrum In this
study, we differentiated between the high and low frequency components of the distress
syllables produced by Carollia perspicillata when under duress. The low and high frequency
components were played to the bats, and the resulting neuronal response was compared to the
response obtained when playing the natural unfiltered calls, which contained both low and high
frequencies. In cortical neurons, the algebraic sum of responses to low and high frequency
syllable-components is lower than the response to the natural call. Thus, suppression appears
to play a strong role in modulating the neural activity to natural, spectrally complex, sounds.
We also noticed that some calls (especially the long calls) evoke very strong activity in all the
recorded neurons irrespective of their frequency tuning. These findings open a door to further
investigation of how neurons are involved in processing vocal communication sounds and
complex acoustic stimuli.
Temperature dynamics during torpor
Nina I. Becker12, Matthias S. Otto1, Klemens Ekschmitt3, Jorge A. Encarnação12
1
Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus-Liebig-University of
Giessen, Giessen, Germany
2
inatu.re, Institute for Applied Animal Ecology and Ecoinformatics
3
Research Centre for Biosystems, Land Use and Nutrition, Justus-Liebig-University of Giessen, Giessen,
Germany.
*Corresponding author: Nina I. Becker, [email protected]
Bats are heterothermic endotherms and use torpor to save energy during diurnal inactivity and
in periods of inclement weather or food shortage. Entry into torpor is characterized by reduced
metabolic rate and declining body temperature. During torpor, body temperature is low and
follows the ambient temperature at the roosting site. To exit torpor, the body must rewarm to
normothermic levels, which is the energetically most costly phase of torpor. In this study we
hypothesized that temperature dynamics during torpor under field conditions are species-specific
and vary with reproductive status. Thermo-sensitive radio transmitters were used to measure
skin-temperatures for six bat species (Myotis bechsteinii, M. nattereri, M. daubentonii, Nyctalus
noctula, N. leisleri and Plecotus auritus). Preliminary results show species-specific differences
in cooling but not in rewarming rates. We tentatively assume that the cooling and warming
processes of torpor are driven by different factors. Microclimatic conditions within roosts appear
to drive cooling rates, whereas fetal development seems to trigger faster warming rates.
41
Mechanical tuning in the cochlea of the fruit-eating bat Carollia perspicillata derived
from suppression of distortion-product otoacoustic emissions
Authors: Manfred Kössl, Christin Reißig, Steven Abendroth
Affiliations: Institute for Cell Biology and Neuroscience, Goethe University, 60438
Frankfurt/Main, Germany
To be able to assess frequency tuning in the cochlea, the suppression of otoacoustic emissions
is a fast method that can be employed noninvasively. It requires the introduction of the tip of
an acoustic coupler into the outer ear canal. The coupler includes a microphone and several
speakers. In our experiments on C. perspicillata, the animals were anaesthetized for a duration
of 2-3h using a Ketavet/Rompun mixture. Distortion-product otoacoustic emissions (DPOAE)
are a consequence of active and nonlinear amplification of low level sound by mammalian
outer hair cells. DPOAE are evoked by using two stimuli of different frequency (f1, f2) and
occur at distinct frequencies like 2f1-f2. To obtain cochlear tuning curves, a third acoustic
stimulus f3 is used to suppress the 2f1-f2 DPOAE by a certain amount (3,6,9,12 dB).
Suppression of DPOAEs in C.perspicillata produces suppression tuning curves (STCs) that
conform to the typical mammalian scheme with a sensitive tip region close to f2. During
suppression, the phase of the DPOAE signal lags at the tip of the STC and leads at the flanks
of the STC. This is consistent with properties of the cochlear amplifier. Tuning sharpness is
moderate and comparable to other hearing generalists that have a good high frequency hearing.
There are no obvious specializations at echolocation call frequencies. In some cases double
tipped tuning curves were measured that had an additional sensitive minimum for frequencies
significantly above f2. When we increased the level of the two stimuli that did evoke the
DPOAE, suppression tuning became sharper and there was a consistent amplitude
enhancement of the DPOAE by application of high frequency ‘suppressors’. The data could
indicate that, while increasing cochlear sensitivity and tuning at low sound levels, the
nonlinear cochlear amplifier may introduce more complex sound shaping at higher sound
levels.
42
Teasing apart cryptic species groups: Implications for species-specific conservation of the
Myotis mystacinus group
Anna Roswag1, Nina I. Becker12, Robert Drangusch3, Kathleen Kuhring3, Bernd Ohlendorf4,
Jorge A. Encarnação12*
1
Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus-Liebig-University of
Giessen, Giessen, Germany
2
inatu.re, Institute for Applied Animal Ecology and Ecoinformatics
3
Workgroup of bat conservation in Saxony-Anhalt e.V., Stolberg, Germany
4
Biosphärenreservat Karstlandschaft Südharz, Landesreferenzstelle für Fledermausschutz Sachsen-Anhalt, Roßla,
Germany
* Corresponding author: Email: [email protected]
The increasing loss of biodiversity and the need to delay the 6th mass extinction on earth resulted
in several international conventions aiming to protect threatened species. Protection advances
with increasing knowledge of the biology and ecology of these species. However, species
numbers exponentially increase with the progressive description of cryptic species. Thus
originally generalistic species are teased apart into several specialized species. The question
arises if detailed knowledge of each cryptic species is essential for effective protection or if they
can be protected by "umbrella" conservation plans that aim at species group level. We studied
the nutrition ecology of three cryptic bat species of the Myotis mystacinus group and compared
the inter- and intra-specific variation. We could show that state-of-the-art methods are able to
detect differences in the nutrition ecology. Based on this we illustrate implications for their
conservation. Protection of key habitat structures at group level will benefit all cryptic members
of the group. Nonetheless, every cryptic species has unique features that are not covered by the
"umbrella" protection and detailed knowledge about these might improve effective conservation
of every single cryptic species.
43
Neuronal responses to amplitude modulation in the bat auditory cortex
Lisa Martin1, M. Jerome Beetz1, Manfred Kössl1, Julio C. Hechavarría1
Goethe Universität Frankfurt am Main, Institut für Zellbiologie und Neurowissenschaft – Dep. Neurobiologie
und Biosensorik, Max von Laue Straße 13, 60438 Frankfurt am Main, Germany
1
Amplitude modulation (AM) is a widely distributed feature of natural vocalisations. Among
other animals, bats and humans use sequences of amplitude modulated acoustic information to
communicate with each other. Amplitude modulated sounds are thought to carry ethologically
important information for the listeners, and this information needs to be extracted by neurons
in the auditory pathway. The aim of this study was to investigate how neurons in the auditory
cortex (AC) of the bat species Carollia perspicillata extract AM information. To that end,
artificially generated acoustic stimuli with different modulation frequencies were presented to
anaesthetised animals and neuronal activity was measured with carbon fibre microelectrodes.
In total, data from 80 neurons was collected. The results show that neurons in the bat AC can
follow AM frequencies up to 8.57 Hz by phase-locking to every cycle of the modulation
envelope. In response to higher modulation frequencies (MFs) up to 2 kHz, a majority of the
neurons generated a burst of spiking activity at the offset of the stimulus. Our data suggests
that bat cortical neurons are rather slow regarding their temporal following capacity, even
though these animals do have to cope with fast time-varying acoustic information on a regular
basis.
44
Vocal signals of bats and mice: making sense of large and diverse vocal repertoires
M. Walter1,2*, M. Eble1*, H.-U. Schnitzler1 and A. Denzinger1
1
Tierphysiologie, Institut für Neurobiologie, Eberhard Karls Universität Tübingen, Deutschland
E-Mail: [email protected]
2
*
Contributed equally to this work
Many mammals produce a great variety of acoustic signals within and across behavioral
contexts, thus providing an often daunting task to us researchers: how to make sense of this large
variation in signal structure. Here, we present a classification approach based on the vocal
repertoire of males from two mammalian orders, the greater mouse-eared bat (Myotis myotis) as
a representative of bats and the harvest mouse (Micromys minutus) as a representative of rodents.
Bat vocalizations were recorded in agonistic interactions between pairs of males and mouse
vocalizations during courtship. In both bats and mice, the vocal repertoire was highly diverse,
resulting in a large number of structurally different vocalizations. We argue that this diversity
can be described as a continuum of related calls. In both species males showed a variable level
of arousal that we determined by analyzing the animals’ behavior. Both behavioral contexts,
aggression and mating, were associated with increased levels of arousal. By arranging the calls
according to the level of arousal of the sender we found a continuum of graded acoustic
structures. The complexity of the signals increased with the caller’s arousal and included the
appearance of multiple types of nonlinear phenomena at high arousal levels. Our approach shows
that a large temporal and structural diversity of vocalizations does not per se reflect different
intentions of the caller. It is more likely a direct effect of the animal’s increased level of arousal
that modulates sound production. The definition of a large number of different call types often
found in the literature is thus highly questionable.
45
Reduction of emission SPL in three common bat species catching a microphone
Julia Löschner1,2, Hans-Ulrich Schnitzler1 und Annette Denzinger1
1
Tierphysiologie, Institut für Neurobiologie, Universität Tübingen
Email: [email protected]
2
When approaching a target bats lower the emission SPL to keep the echo SPL in an optimal
range for auditory processing. Reduction rates given in the literature range from 4-9 dB per
halving of distance (dB/hd). So far it is not fully understood what determines the reduction
rate. In this study we measured the amplitude of echolocation calls of Myotis nattereri,
Myotis mystacinus/brandtii and Pipistrellus pipistrellus in the field recorded when catching the
microphone of a batcorder. We hypothesized that during the approach bats only compensate
for the rise of the SPL measured at the target caused by geometric spreading (6 dB/hd) which
would result in a constant SPL measured at the microphone. This would give the bat the
possibility to collect additional information of the quality (reflection properties) of the target
by evaluating the dynamic changes in echo amplitude over successive echoes; eg., point targets
get louder by 12 dB/hd whereas the reflecting properties of a mirror target like a wall would
result in an increase of 6 dB/hd.
In all species the approach to the microphone of the batcorder was longer than the approach to
real prey targets, indicating that the batcorder was detected earlier, and/or that bats approached
it with a lower speed, and/or that they hovered during the approach. In search flight the
amplitude at the microphone increased as predicted by atmospheric spreading but during
approach it was kept constant or decreased, indicating that all bats species reduced emission
SPL when approaching the microphone, although in different manners. In the near edge space
forager M. nattereri the approach phase was rather long and the emission SPL was kept almost
constant at the microphone. The long duration may partly mirror hovering phases in front of
the microphone without changes of emission SPL. The constant SPL in the non-hovering
phases indicated a rather exact reduction with 6 dB/hd. The more in the open hunting edge
space forager P. pipistrellus compensated less precisely, and the decrease of the signal SPL at
the microphone indicated a compensation of more than 6 dB/hd. M. mystacinus/brandtii was
somewhere in between.
The closer a species forages to the background the more precise the compensation rate was
kept at 6 dB/hd, which may indicate that near edge space foragers use the dynamic changes of
the echo SPL in successive calls to discriminate between background and prey echoes.
46
Ultrasonic vocalizations of male harvest mice Micromys minutus during courtship
Myrna Eble and Annette Denzinger
Animal Physiology, Institute for Neurobiology, University of Tübingen
E-Mail: [email protected]
Ultrasonic vocalization (USV) is a common type of communication among rodents. In mice
USVs are an essential part of courtship behavior and differ according to the behavioral context
and the affective state of the emitter. The present study examined for the first time USVs of
male harvest mice (Micromys minutus) during courtship behavior. We synchronously recorded
the behavior and the call repertoire of male harvest mice during courtship, assigned the USVs
to call types according to their complexity and investigated which call types occurred during
the single stages of courtship behavior.
USVs were assigned to four different call types that represent a graded continuum with
increasing completeness and complexity. Call type 1 consisted of a v-shaped component,
which occurred in all four call types. Call types 2 and 3 additionally contained one frequency
jump. Call type 4 was a combination of all call types and exhibited the complete structure of
USV containing two frequency jumps. Moreover, calls differed in their structural complexity:
some calls contained in addition to the 1st harmonic also the 2nd harmonic and/or subharmonic
structures as well as chaotic components. All males emitted all call types.
The courtship of harvest mice comprised a succession of five different behaviors that occurred
mostly in the same order: approach, nose-dance, chasing, anogenital sniffing and mounting.
Besides these five mating related behaviors four non-mating related behaviors (close sitting,
grooming, exploration and sitting) were observed during which predominantly simply
structured calls were emitted. The most complex calls, type 4, occurred almost exclusively
during mating related behaviors and structural complexity was generally higher in mating
related than in non-mating related behaviors. Our data show that USVs of male harvest mice
represent a dynamic continuum, that consist of one call type which is modulated according to
the males’ level of arousal.
47
Thermoperception and temperature discrimination in a frugivorous bat
Samuel Kaiser & Holger R. Goerlitz
Acoustic and Functional Ecology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319
Seewiesen
The ability to sense temperature differences is widespread within the animal kingdom. A range
of different sensory cells and organs evolved for thermoperception, enabling animals to find
mates, detect prey or fruit. Crotaline and Boid snakes, for example, use infrared radiation to
detect their prey. Insects use it for finding new breeding grounds, like the beetle Melanophila
acuminata. The butterfly Pachliopta aristolochiae uses thermoperception to adjust the amount
of received sun radiation by changing its wing angle. Within mammals, the common vampire
(Desmodus rotundus) is well-known for its ability to sense temperature differences, potentially
using this ability to detect (the blood-vessels of) warm-blooded animals. Beside detecting warmblooded prey, however, thermoperception may also be beneficial for detecting and locating other
warm objects. Some tropical fruit such as figs become significantly warmer than its environment
during ripening. Locating centimeter-sized objects in dense tropical forest by echolocation is
challenging. For this reason, specialized echo-acoustic beacons evolved in bat-pollinated plants
to attract bats. Likewise, radiating a thermal signature might be beneficial to attract seed
dispersers. The neotropical lesser spear-nosed bat Phyllostomus discolor is an omnivorous bat
who feeds to a large amount on different fruit items. Like the common vampire bat, it belongs
to the family Phyllostomidae and thus might possess the ability for thermoperception, potentially
used for fruit detection. Here, we investigated thermoperception in P. discolor by measuring its
temperature discrimination threshold in a two-alternative forced choice experiment. Eight bats
were trained to approach the warmer of two plates with diameters of 55, 90 and 140 mm.
Temperature differences ranged from ΔT of 45 °C to 5 °C relative to a neotropical-like room
temperature of 25°C. We will present learning curves for temperature discrimination at large ΔT
and temperature discrimination performance for different ΔT values.
48
Former settlements serving as multifunctional roosts for Rhinolophus bats
Winter R1., Schmidt S.2 & J. Mantilla Contreras1
1
Institute of Biology and Chemistry, University of Hildesheim, Germany
Institute of Zoology, University of Veterinary Medicine Hannover Foundation, Germany
Corresponding author: [email protected]
2
The loss of adequate foraging habitats and roosts is the biggest threat for bats in Europe.
Especially cave dwelling Rhinolophus bats showed dramatic declines during the last decades
and thus are highly protected nowadays. Former settlements, with a large amount of
uninhabited structures may therefore provide adequate roosts for these species. We examined
the role of uninhabited settlements for bats on the former prison island and National Park
Asinara, in Sardinia, Italy. Man-made structures on the island were checked for cave dwelling
bats in summer 2014 and roosts were regularly monitored from January to September 2015.
Species, number of individuals and roost type were recorded. We defined six different roost
types: ‘regular day roost’, ‘temporary day roost’, ‘night roost’, ‘nursery’, ‘temporary nursery’,
‘winter roost’ and ‘not monitored’ roost, where bats were present but further monitoring was
not feasible. Data loggers recorded temperature and relative humidity inside roosts once per
hour. Often a structure provided several roost types, thus 36 different structures harbored 65
roosts. 44 of them were used by R. hipposideros, 10 by R. ferrumequinum and 11 by both
species but only in 3% of controls the species were found perching in the same room.
Nurseries, exclusively of R. hipposideros, were detected in cisterns and rooms of houses.
Microclimate differed significantly between roost types and in relation to the inhabiting bat
species. The results show that man-made structures are of high value for bat conservation, and,
additionally allow a cost effective monitoring of bat populations. As these structures provide
different microclimatic conditions, they may play a key role as alternatives for natural roosts,
especially in view of the ongoing climate change.
49
DIET OF TWO BAT SPECIES (RHINOLOPHUS HIPPOSIDEROS & R. FERRUMEQUINUM) ON
ASINARA ISLAND, SARDINIA
V. WESKE1, R. WINTER1, A. BLÖCHL², S. SCHMIDT3 & J. MANTILLA-CONTRERAS1
1
Institute of Biology and Chemistry, University of Hildesheim, Germany
²Division of Cell Biology, University of Veterinary Medicine Hannover Foundation, Germany
³Institute of Zoology, University of Veterinary Medicine Hannover Foundation, Germany
Corresponding author: [email protected]
In the last 50 years, Rhinolophus populations have declined due to the loss of roosts and
foraging habitats. To protect present colonies of the endangered species, information about
roosts and foraging habitats are essential. To understand the quality of a foraging habitat, data
about the potential prey and the species’ dietary requirements are necessary for evaluating
habitats adequately. Therefore, we studied prey availability as well as insects consumed by R.
hipposideros and R. ferrumequinum in the Asinara Island National Park. Due to the high
amount of grazing animals on the island, the role of dung beetles as prey was also investigated.
Insects were assessed to order using light trap capture data from 2013 and 2014. To check
which taxa were actually eaten, the diet of the two species was studied by analyzing insect
fragments in faeces. Droppings were collected once a week from May to July 2015 at a day,
and a night, roost of each species. 44 droppings of R. hipposideros and 40 of R. ferrumequinum
were analyzed. We determined presence-absence data of insect orders and the main prey
component per dropping. Lepidoptera, Hymenoptera and Coleoptera were predominant in light
trap captures. In droppings, we identified fragments of seven insect orders, i. e. Lepidoptera,
Hymenoptera, Diptera, Coleoptera, Neuroptera, Orthoptera and Hemiptera, as well as spiders.
In droppings of R. hipposideros, we determined fragments of six insect orders as well as of
spiders. In droppings of R. ferrumequinum, seven insect orders were identified. Lepidoptera
was the most present order in droppings of both species. Significant differences in the diet of
the two species were ascertained for Hymenoptera, Neuroptera and Diptera. Composition of
droppings in day and night roosts showed no significant differences. Neither in light traps, nor
in droppings a considerable amount of dung beetles was found. First results indicate that both
species forage opportunistically but with slight differences in taxon ranking at least on a
presence-absence level. Similar insect compositions in droppings of day and night roosts show
that the same taxa are consumed throughout the night. An effect of grazing animals on prey
availability via dung beetles was not confirmed. Differences in diet may be based on e. g. bats’
body size, call frequency and foraging strategy.
50
Ecology of coronavirus infection in Ghanaian bats
Heather Joan Baldwin1,2, Victor Max Corman3,X, Evans Ewald Nkrumah4, Ebenezer Kofi Badu4,
Priscilla Anti4, Augustina Angelina Annan4, Michael Owusu4, Olivia Agbenyega4, Samuel
Kwabena Oppong4, Stefan M. Klose1, Yaw Adu-Sarkodie4, Adam J. Stow2, Peter Vallo1,5,
Elisabeth K. V. Kalko6, Jan Felix Drexler3,7, Christian Drosten3 and Marco Tschapka1,6.
Author affiliations: 1Ulm University, Ulm, DE; 2Macquarie University, Sydney, AU; 3Bonn University, Bonn, DE;
4
Kwame Nkrumah University of Science and Technology, Kumasi, GH; 5Academy of Sciences of the Czech
Republic, Brno, CZ; 6Smithsonian Tropical Research Institute, Panama City, PA; 7German Centre for Infection
Research, partner site Bonn-Cologne, DE
Bats are hosts of several coronaviruses (CoV) causing zoonotic diseases, including SARS and
MERS. Individual- and population-level risk factors assessment for CoV infection in bats was
conducted in cave-dwelling bats in Ghana, West Africa. Widespread CoV infection was
revealed, with seven of 17 sampled bat species infected with CoVs belonging to several Alphaand Betacoronavirus lineages. Juvenile bats had substantially higher risk of infection than
adults. Temporal variability of infection may indicate an important role of juveniles and
seasonal roosting behavior in CoV amplification. Ectoparasitic infection showed varying
degrees of positive association with CoV infection, and there was evidence that lower body
condition may increase the infection risk. Our results help to better understand ecological,
demographic and seasonal processes that influence CoV infection dynamics in bats. Avenues
on which to focus future strategies for the prediction and prevention of zoonotic CoV outbreak
could be devised, including avoiding.
Cues for prey detection: what about the water surface?
K. Übernickel, Uni Tübingen
In the context of the ongoing discussion about auxiliary cues for prey detection we focused on
the possible information provided to the greater bulldog bat Noctilio leporinus by water
surface disturbances created by prey movements. To estimate the chances of detection we
measured via ensonification the target strength of echoes produced by punctual water
disturbances. Our artificial echolocation-like constant frequency (CF) and frequency
modulated (FM) sounds revealed that both, a water splash and the subsequently expanding
ripples, may be detected with both types of ultrasound calls. We compared the results to
measurements of constant prey cues and also calculated maximum detection distances. Our
results indicate that water surface disturbance patterns are detectable for this bat and may
provide auxiliary cues for prey detection.
51
Escaping a bat: Behavioural variability as anti-predator adaptation in moths
THERESA HÜGEL1*, HANNAH M. TER HOFSTEDE2, HOLGER R. GOERLITZ1
1
Acoustic and Functional Ecology Group, Max Planck Institute for Ornithology, Eberhard-Gwinner Straße 11,
82319 Seewiesen, Germany
2
Dartmouth College, Department of Biological Science, 78 College St, Hanover, NH, 03755, USA
*author for correspondence: [email protected]
How to not end up as a predator’s meal? This question is crucial for animals of prey; and
therefore a multitude of adaptations for avoiding or escaping predators evolved. One of the
widespread adaptations is erratic and therefore unpredictable movement known as “protean
behaviour”. Echolocating bats and eared moths are ideal to study this kind of behaviour. Upon
detecting a bat with their ultrasound sensitive ears, many moths engage in evasive flight
manoeuvres to escape the attacker. Previous studies already revealed that moths´ escape flight
behaviour consists of two stages, directional and erratic flight. Surprisingly however, erratic
flight seems to show some degree of stereotypy. As successful defence behaviour is mainly
based on unpredictability, an open research question is how such stereotypical behaviour can
be effective for avoiding predators. We hypothesize that interspecific variation in evasive
flight exists across moth species, causing a masking effect of the stereotypy of the evasive
flight of any single moth species. We recorded the evasive flight behaviour of multiple
European and North-American moth species using two different approaches. (A) Using an
automated force-transducer we recorded behavioural audiograms of stationary flying moths.
Pure tone stimuli from 5-90 kHz were presented in randomized order and with increasing
intensity of 20-90 dB SPL to flying moths. (B) To observe natural flight behaviour, we
recorded 3D trajectories of free flying moths in a sound-attenuated and anechoic acoustic
chamber in response to pure tone pulses of 30 kHz at 50, 65 or 80 dB SPL. Analysing
behavioural thresholds (A) and the onset and three-dimensional shape of escape trajectories
(B) will enable us for the first time to systematically compare moth escape flight across
multiple species, to compare behaviour to the underlying neuronal audiograms, and to study
additional factors like moth size and echo reflectivity on escape behaviour. In sum, this will
shed light on the specialised adaptations that evolved in prey species in response to the threat
posed by their highly specialized predators, nocturnal flying echolocating bats.
52
Acoustic and ecological similarity as factors for echolocation-call mediated interspecific
information transfer in wild Myotis bats
THERESA HÜGEL1,2,3, VINCENT VAN MEIR1,2, AMANDA MUÑOZ-MENESES2, B.-MARKUS
CLARIN1, BJÖRN M. SIEMERS1,†, HOLGER R. GOERLITZ1,2,*
1
Sensory Ecology Group, Max Planck Institute for Ornithology, Eberhard-Gwinner Straße 11, 82319 Seewiesen,
Germany
2
Acoustic and Functional Ecology Group, Max Planck Institute for Ornithology, Eberhard-Gwinner Straße 11,
82319 Seewiesen, Germany
3
Department of Animal Ecology and Tropical Biology (Zoology III), Julius-Maximilians-University, Am
Hubland, 97074 Würzburg, Germany
*author for correspondence: [email protected]
Recognizing species identity is crucial for many aspects of animal life and directly relevant to
fitness. A strong selection pressure exists in mating to distinguish conspecifics from sympatric
similar species. Additionally, distinguishing between sympatric heterospecifics should be
beneficial, for example for following ecologically similar heterospecifics to suitable roosting
and foraging sites. The information transfer required for this ability might be mediated by
multiple cues and signals, with acoustic signals playing a major role in many taxa including
insects, anurans, birds and mammals. In bats, echolocation evolved for sound-based orientation
and foraging of the calling individual, yet it also contains diverse information about the calling
individual with can be perceived by close-by individuals. Increasing evidence supports the
communicative function of echolocation within species, yet data about the role of echolocation
calls for interspecific information transfer is scarce. Here, we asked if bats extract information
from heterospecific echolocation calls, which information they extract, and if they use it for
their own decision making during foraging. We tested the ecological similarity and the
acoustic similarity hypothesis that propose different sensory and cognitive mechanisms
underlying this information transfer. In three lab- and field-based playback experiments, we
tested if foraging bats (M. capaccinii and M. daubentonii) approached the foraging calls of
conspecifics and four heterospecifics that were similar in foraging ecology only (ecological
similarity hypothesis), acoustic call structure only (acoustic similarity hypothesis), both, or
none. In the lab, bats only approached calls of M. capaccinii and M. daubentonii, and only
showed a very weak positive response to these species in the field. Our results confirm
information transfer across species boundaries, yet cannot decide on the underlying mechanism
which might be based on acoustic similarity only or on a combination of acoustic and
ecological similarity. Furthermore, the mostly lacking response in the field highlights the
importance of environmental factors and the need for studying animal behaviour where it
really happens, in the field.
53
All-winter rehabilitation of Nyctalus noctula, Kharkiv (NE Ukraine)
Kseniia Kravchenko1,2,3, Anton Vlaschenko1,2, Olena Rodenko1,2,4, Vitalii Hukov1,2
1
Bat rehabilitation center of Feldman Ecopark, Kharkiv, Ukraine,
e-mail: [email protected]
2
Ukrainian Independent Ecology Institute, Kharkiv, Ukraine
3
Leibniz-Institute for Zoo and Wildlife Research
4
University of Silesia in Katowice
The study presents the results of rehabilitation of group of Nyctalus noctula (N=97) during the
winter 2014/2015 in Bat Rehabilitation Center (BRC) of Feldman Ecopark (Kharkiv, Ukraine).
Since 1990th, crevices in old prefabricated blocks of flats in eastern Europe become occupied
by bats (mostly N. noctula) during autumn and winter. It causes multiple conflicts between
bats and citizens. Quite frequently during reparatory or rebuilding works in such buildings the
roosts are destroyed and bats are thrown away. Such group of abandoned N. noctula from the
destroyed cavity was saved by staff of BRC and was kept in artificial hibernation condition
from December 2014 to March 2015. For each individual sex, age and reproductive status were
evaluated (if possible). Forearm length and body mass (by digital scale to 0.1 gram) were also
measured. All individuals were surveyed for presence of any injures or traumas. After 37 days
of hibernation all individuals were weighted again. These bats which have insufficient weight
were additionally hydrated and fed during continuous several days and then were put again
into cool temperature condition for hibernation. Since then, such checkups take place in
average each two weeks. For each individual was made a data base, where the information
about weight check, feeding or hydration actions was fixed. After analyses of these cards we
estimated the survival rate of the N. noctula during hibernation, their weight dynamics and
effect of additional feeding and hydrating.
54
Vocal Production Learning in Adult Phyllostomus discolor
Ella Z. Lattenkamp1,2, Sonja C. Vernes2, and Lutz Wiegrebe1
1
AG Wiegrebe, Division of Neurobiology, Ludwig-Maximilians University Munich, DEU
Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, NDL
2
Bats have a highly specialized audio-vocal system, which allows not only for echolocation but
also for rich acoustic communication. Most bat research has focused on their echolocation, but
recently they have started to attract attention for being a well-suited mammal model for vocal
learning. Several bat species are known to have an extensive call repertoire and to exhibit a rich
pallet of communicative interactions. Not only sophisticated syllable- and song formation was
demonstrated, but some bat species have also shown indications of ‘vocal production learning’,
i.e. the acquisition of non-innate communication calls, which further adds to the flexibility of
the vocal repertoire.
Here we aim to establish a psychophysical behavioral paradigm that allows testing for vocal
production learning in adult P. discolor under fully controlled laboratory conditions: we
developed a multistage training plan, in the course of which adult bats will be trained via an
ultrasonic intercom to adjust their calls according to real-time manipulated auditory feedback.
With the help of food rewards, adult bats will be trained to adjust parameters of their own calls
to match or compensate real-time modified playbacks of their calls. Modifications include
changes of the fundamental frequency (‘pitch’) or energy content of the harmonics (‘formants’),
among others. Via multivariate call analyses, we will assess the calls before and after the training
period and will thus be able to detect significant changes in call parameters, signifying vocal
entrainment by the bats.
Targeted real-time modifications will allow us to investigate the ability of adult Phyllostomus
discolor to imitate artificially modified calls by independently adjusting properties of their
phonatory system (the vocal folds for e.g. controlling fundamental frequency) and filter system
(the vocal tract for e.g. formant formation).
55
The bat-moth arms race goes on: Barbastelle bats lead through the combination of lowintensity echolocation and intensity compensation
DANIEL LEWANZIK, HOLGER R. GOERLITZ
Acoustic and Functional Ecology Research Group, Max Planck Institute for Ornithology,
Eberhard- Gwinner-Str. 11, 82319 Seewiesen, Germany.
The predation pressure of insectivorous bats on their insect prey led to the evolution of ears in
several insect taxa. Eared moths perform evasive flight manoeuvres when they hear bat
echolocation calls, thereby decreasing their risk of predation. Yet, barbastelle bats, Barbastella
barbastellus, are able to capture eared moths in large quantities. We hypothesized that
barbastelles lower the intensity of their anyway low-intensity search calls while closing in on
their prey, such that the intensity at the moth’s ear remains below the moth’s hearing threshold
until capture and the moth fails to elicit its life-saving evasive manoeuvre. Yet, in many
vertebrate taxa, background noise causes an increase in vocalisation amplitude. Thus, we further
hypothesised that background noise alters the predator-prey interaction between barbastelles and
moths.
We tested these hypotheses in both the wild and captivity by offering tethered moths to
barbastelles under silence and noise conditions. We reconstructed the bats’ three-dimensional
flight paths based on time-of-arrival differences of the echolocation calls at four microphones,
measured the received sound levels at the moth’s position with an additional miniature
microphone, and calculated call source levels.
We show that barbastelles continuously reduced call intensity upon detecting a moth, thereby
remaining below the moth’s hearing threshold and rendering the bat’s approach undetected by
its prey until shortly before capture. Background noise caused an increase in call intensity.
Barbastelles have combined intensity compensation with low-intensity echolocation to counter
moth hearing during an attack. This novel strategy might have given them exclusive access to a
formerly unavailable food source, thereby probably altering competition between sympatric bat
species tremendously. In turn, selection pressure for eared moths might have increased,
potentially fostering new anti-bat traits to evolve. Yet, increased source levels in noisy
environments could foil the bat’s stealth strategy if the moth’s hearing threshold remains the
same.
56
Global transition from conventional to LED street lighting may be advantageous for lightaverse bats, but disadvantageous for light-tolerant species
DANIEL LEWANZIK, CHRISTIAN C. VOIGT
Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße
17, 10315 Berlin, Germany & Department of Animal Behaviour, Freie Universität Berlin, Takustraße 6, 14195
Berlin, Germany
Light pollution can have deleterious effects on biodiversity, but light types differ in their effect
on wildlife. Among the light types used for street lamps, light emitting diodes (LEDs) are
expected to become predominant globally within the next few years.
We investigated how the pervasive replacement of conventional illuminants by LEDs affects
urban bat communities: in a large-scale field experiment we compared bat activity at municipal
mercury vapour (MV) street lamps which were replaced by LEDs with control sites that were
not changed.
Pipistrellus pipistrellus and bats of the Nyctalus/Eptesicus/Vespertilio group were 45% and 31%
less active at LED than at MV street lamps, respectively, while light type did not affect activity
of Pipistrellus nathusii and Pipistrellus pygmaeus. Bats of the genus Myotis increased activity
4.5-fold at LEDs when compared with MV lights.
Our results suggest that the anthropogenically introduced competitive advantage for light
tolerant species, namely the ability to selectively forage on insect aggregations at artificial lights,
diminishes at LEDs. Light averse species, in contrast, might even benefit from LEDs, since
LEDs seem less repelling to light averse bats and remove fewer insects from adjacent dark
habitats than MV lights. Thus, the anticipated wide-spread transition from conventional lighting
techniques to LEDs may largely alter the anthropogenic impact of artificial light on urban bat
assemblages and might eventually affect bat populations’ development. Further, a reduced
selective hunting pressure on insects at LEDs is likely to have far reaching consequences for
biodiversity and ecosystem functioning through cascading effects via the food web. Yet, we
argue that the global spread of LED street lamps might help to head towards a more natural level
of competition between light tolerant and light averse bats. The potential benefits of LEDs could
be swept off, though, if low costs foster an overall increase in artificial lighting.
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Neuronal tuning to natural echolocation sequences in the inferior colliculus of the fruiteating bat Carollia perspicillata
Authors: Sebastian Kordes, M. Jerome Beetz, Julio C. Hechavarría, Manfred Kössl
Authors’ affiliations: Institute for Cell Biology and Neuroscience, Goethe University, 60438
Frankfurt/Main, Germany
Cortical neurons of the fruit-eating bat Carollia perspicillata are suppressed and more sharply
tuned when stimulated with natural echolocation streams than with single pulse echo elements
of the sequence that were separated by a 400 ms silent period. At present it is unclear, whether
subcortical neurons are also suppressed in response to fast echolocation streams, or more
generally, how they process natural echolocation streams. Therefore multi-unit recordings
from the inferior colliculus of anaesthetized and awake bats were preformed while the animals
were passively listening to natural echolocation sequences. Two different stimulation protocols
were used. A simple one where the echolocation sequence consisted of echo information from
one object and a complex stimulus where the echolocation sequence included echoes from up
to three different objects that were separated along the depth axis.
The data reveal that suppression at subcortical level is relatively weak in comparison to the
suppression occurring at cortical level. Suppression was mainly manifested in a reduction of
spontaneous activity. In comparison to the strong delay selectivity in cortical neurons,
collicular neurons responded equally well to each pulse echo element of the echolocation
sequence. Our data indicate that the time point of pulse and echo occurrence is highly
conserved in the inferior colliculus. This implies that in contrast to other species like the
mustached bat, no typical delay tuning as described in cortical neurons of C. perspicillata has
been found at midbrain level. Neuronal data during stimulation with the multi-object
echolocation sequence (complex stimulus) show that each of three objects was almost equally
represented by the unit which emphasizes that collicular neurons did not show selective
suppression as cortical neurons do.
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