Submission re the importation of the Red-eared firetail finch Stagonopleura oculata into Tasmania.
Red-eared firetail by Trevor Hetherington
Preface:
My name is Marcus Pollard and I hold a Bachelor of Science with Honours from the
University of Tasmania. My Honours project was completed on the endemic Green
Rosella, Platycercus caledonicus.
In 1999 I completed a number of Environmental Impact Statements' (EIS) for a
number of exotic aviary finch species which were under threat from proposed federal
legislation. I was able to do so successfully for all species such that they were added
to the Tasmanian avian permitting system of the time.
I was again able to demonstrate the advantages of the captive breeding that we
were undertaking at the time involving the Swift parrot, Lathamus discolor, where we
were so successful with this species we rewrote its husbandry manual. It is now a
common avicultural species as a result of this research and we subsequently
published most of our finding in a plethora of national and international avicultural
journals.
As a laboratory manager at the Menzies Research Institute I have written numerous
hazard statements and completed a number of risk analysis investigations as part of
my OH&S duties.
Summary:
Red-eared firetail finch - Stagonopleura oculata. (Quoy & Gaimard, 1830).
The species is endemic to south-western Western Australia - mainly between 31ºS
and 121ºE in the Darling Range and between Esperance and Duke of Orleans Bay
(Clement, et.al 1994).
There is no record of this species ever establishing feral populations outside of its
natural range, in fact its population has been shrinking rather than enlarging.
Has had no impact on humans throughout its natural range. I was unable to find any
incidences of adverse behaviors directed at agriculture, disease or any forms of
human habitation.
As such a shy and secretive bird it is rarely even seen and appears to shun human
habitation. It has a rare status in aviculture in Australia and has never established
escapee populations here or anywhere else in the world.
Given the moderate score in Climatch of 3, it's extremely low numbers in captivity
there is little potential likelihood that the species could be reasonably expected to
establish in the Tasmanian bush. It has never produced hybrids with any other
Estrildid species – not even members within its own genus.
The species will/may be a new import into Tasmania and as such there are none of
these finches currently in Tasmania as far as we are aware.
The benefits are that, as an extremely difficult species to keep and breed, it will allow
selected breeders here the opportunity to gain further expertise in the captive
husbandry of another endangered Australian species.
Given the concerns that CALM in Western Australia have for the species long-term
survival; captive breeding programs may prove advantageous to the species in the
long-term by providing valuable information on the Ethology of the species albeit in
captivity.
One member of the Stagonopleura genus, the Beautiful firetail, S.bella, exists in the
wild in Tasmania, but any fears about hybridisation or competition would be illfounded given that the Red-eared firetail has never produced hybrids with any other
species of Estrildid finch. Its rarity alone would preclude any such event and as
further evidence of this the other member of the Stagonopleura genus – the
Diamond firetail, S.guttata – is amongst the commonest of Tasmanian aviary finches
and none have managed to establish populations in the Tasmanian bush or ever
been recorded producing hybrids with either the Beautiful or the Red-eared firetail
finches in the wild or in captivity (Kingston, 2010) Further to this the climatic match
with Tasmania for the Diamond firetail is high and yet no escapees exist while the
Climatch for the Red-eared is low-moderate for Tasmania.
Any hybridisation concerns between members of the Stagonopleura genus are
further placated by the fact that the natural range of the Diamond and Beautiful
firetail overlap on the mainland yet no hybrids have been recorded in the wild - which
again suggests any such concerns are ill-founded based on the historical record.
This is further supported by the uncommon frequency of hybrid finches recorded in
the wild where the range of Chestnut-breasted, Lonchura castaneothorax, and Yellowrump finches, L.flaviprymna, overlap – two closely aligned species (Myers,
pers.comm.).
However, in captivity there are records of these two Lonchura species occasionally
producing hybrids if kept together in direct contrast to the Firetail group.
Due to its moderate Climatch score the conditions required to keep the Red-eared
Firetail in Tasmanian aviaries would preclude any more than a few specialist
breeders obtaining and holding the species in this state. Couple this with its
demanding husbandry & rarity in captivity it would be extremely unlikely that this
species has the potential to ever make it into main-stream aviculture in Australia let
alone in this state.
It will further allow other aviculturists to develop their own husbandry skills with no
threat to the Tasmanian environment or Biodiversity.
This species was imported into Tasmania at least once as around 14 birds were sold
through a Hobart pet dealership in the mid 1970’s (Oliver, pers.comm.). The fate of
these birds is unknown and they have certainly not been available to mainstream
aviculture here since.
This submission is on behalf of Allan Oliver of Sandford Tasmania.
The Species:
The species is the Red-eared firetail, Stagonopleura oculata.
Full classification:
Kingdom: Animalia
Phylum:
Chordata
Class:
Aves
Order:
Passeriformes
Family:
Estrildidae
Genus:
Stagonopleura
Species: S. oculata
There are no recognised sub-species/races recorded for this species or is
there any evidence of geographical variation within the species:
It was clear from the large array of reference material available that the Red-eared
firetail has never been recorded as hybridising with the other 2 species in its 'group' the Beautiful firetail, S.bella, and the Diamond firetail, S.guttata.
The Beautiful firetail occurs in Tasmania and is a locally common species in the wild.
The Diamond firetail is among the most common Australian aviary species held in
Tasmanian aviaries.
The trade name for this species is the Red-eared firetail finch.
It may occasionally be referred to as the Casuarina finch, Native sparrow or simply
as the Red-eared.
There exists little taxonomic uncertainty within this species - no mutations are
recorded and no sub-species recorded. There is little chance of misrepresentation
with this unique species as it is the most striking of all the Australian grassfinches
save for the Gouldian finch.
Also there would appear to be little chance of hybrids being produced given none
have ever been recorded in the history of aviculture world-wide.
It also shares its home-range with the introduced Red-browed finch, Neochmia
temporalis, - another Estrildid species - but again, no hybrids have ever been
recorded.
Description:
This species is monomorphic.
The Red-eared firetail is around 120mm in length and weighs around 13grams.
The general upper body colour is olive-brown, finely barred with black or blackish
grey. This barring transgressing from being broader and more conspicuous on the
back and wing coverts to becoming finer, closer spaced and less distinguishable on
the head. The lores and feathers around the eyes are black. The areas below and
behind the eye, including some of the upper ear coverts, are bright red. As per all
members of the firetail family, the rump is a shiny bright red. The Primaries and
secondaries are a dark brownish grey edged with a narrow band of pale or olive
grey. The tail is generally olive grey and finely barred with black, with the bars almost
merging at the base of the tail to give it a black tipped appearance. The chin, throat
and breast are a buff brown finely barred with black. The feathers on the sides of the
breast, the flanks and under-tail coverts are black and barred or boldly spotted with
white. The iris is brown, whilst the skin around the eye is a pale blue to bluish-grey.
The bill is red and the legs dark brown (McCrae, 2007).
The male Red-eared firetail however, undergoes subtle transformations when
approaching breeding condition. Firstly their beak darkens to an almost crimson red.
Simultaneously, the ear patches change from a bright red to a brilliantly, deep scarlet
red. The female on the other hand undergoes no apparent transformation (McCrae,
2007).
Juveniles: Appear as a dull grey with poor definition of the black lines through the
plumage and the beak is a black colour. The change from juvenile to adult takes
around 10-14 weeks to occur (McCrae, 2007).
Other Information: There are no recorded colour morphs or mutations recorded for
this species in the available literature or among those that have observed them in the
wild.
Hybrids with other Fringillid or Estrildid finches were not recorded either in the wild or
in captivity in the literature scanned.
Given its striking colouration it has no even superficial resemblances to any native
species that exists in the Tasmanian environment. The only trait it shared with the
native Beautiful firetail is its characteristic red tail coverts.
Even in captivity it is so distinct that it is very difficult for even the novice finch keeper
to confuse its identity with other common aviary finch species.
Conservation & Legal Status:
The Red-eared firetail finch is considered a species of “Least Concern” on the IUCN
(International Union for Conservation of Nature) and was last assessed by BirdLife
International in 2009. Their reasons for thus grading the species as such were:
“Although this species may have a restricted range, it is not believed to approach the
thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2
combined with a declining or fluctuating range size, habitat extent/quality, or population size
and a small number of locations or severe fragmentation). The population trend appears to
be stable, and hence the species does not approach the thresholds for Vulnerable under the
population trend criterion (>30% decline over ten years or three generations). The population
size has not been quantified, but it is not believed to approach the thresholds for Vulnerable
under the population size criterion (<10,000 mature individuals with a continuing decline
estimated to be >10% in ten years or three generations, or with a specified population
structure). For these reasons the species is evaluated as Least Concern. (The Red List 2010
- http://www.iucnredlist.org/apps/redlist/details/149388/0)
Within Australia in order to hold the Red-eared firetail requires the top specialist-type
license in most states.
For example in Queensland you require a Class 1 Restricted License, in Victoria an
Advanced License, in NSW a Class 2 License, in South Australia a 'Specialist Permit
to Keep and Sell Protected Animals' is needed and in Western Australia an
Advanced Avicultural License.
As an Australian native species it is not listed by the Vertebrates Pest Committee
and hence has no rating.
The import will not constitute any international effort to breed the species given its
status of Least Concern with IUCN.
However, it is part of a national initiative within finch aviculture to ensure that the
species is sustained within aviculture for the foreseeable future. To this end it is a
desired outcome to have the species in the hands of those breeders best able to
reproduce the species and ensure its longevity, albeit in captivity.
Further to this is with the demand for land in the Perth environs there has been a
shift in thinking towards the preservation of certain bird species through advanced
captive breeding programs. Selected aviculturists have been allowed to trap then
breed threatened species in captivity with the permission of Western Australia’s
Department of Conservation and Land Management (CALM) – this includes the Redeared firetail finch. (Burke, 2005)
It is inconceivable that this species would ever be available to the average back-yard
finch hobbyist due alone to its highly demanding breeding ethology and high price –
stated without any intended slur to any Tasmanian finch breeder residing in this
state.
Life History:
There appears to be no studies undertaken of breeding in the wild and most records
are from captive finches (Higgins, et.al, 2006)
The breeding season of the Red-eared firetail finch in captivity in Australia
commences around early September and the birds construct a large football sized
nest in bushes and small trees.
The breeding nest has a funnel attached to the front of the nest and there is little
attempt to actually hide the nest structure.
4-5 white eggs are laid and fertility is around 75% currently so it is to be expected
that 2-4 chicks will be raised per nest. The usual number of nests in a given season
is 2 or 3 depending on the pair (McCrae, pers.comm.).
The incubation period is around 12-16 days and is undertaken by both sexes.
The fledging time is around 21-24 days.
Full independence is not obtained until 3-4 weeks after leaving the nest. (Kingston
2010)
The species has a reputation for aggression during the breeding season which some
attribute to its solitary life style when breeding in the wild.
In the confines of the aviary it can react badly to the close proximity of others of the
same species and young must be removed as soon as independent as the parents
frequently turn on them with catastrophic results. Many of the breeders currently
holding the Red-eared firetail are attempting of use fostering as a means of removing
this natural aggression and establishing a captive strain suitable for colony breeding
(McCrae, 2007)
Breeding age would appear to be possible at around 6 months of age but best
breeding results are achieved from one year old birds.
There is no recorded evidence of sperm storage but I believe that this is not a
characteristic of this avian species – certainly not a documented one.
As previously stated there are no records of hybridisation between this species and
any other avian/Estrildid species.
As mentioned the close confines of the aviary environment contrast markedly with
their extensive natural habitat so there may be displays of aggression when this
species is forced into close proximity to other species.
Habitat Requirements and Preferences:
The Red-eared firetail finches natural habitats are the forests and coastal thickets of
south-western Western Australia. It tends to be found in the riparian zone in these
locales.
They are rarely recorded around human habitation which would preclude any
concerns over their impaction upon any agricultural land uses – not that there is any
recorded evidence of their having any deleterious effects on any human land use.
Natural Geographical Range:
This species occurs in the forests and coastal thickets of south-western Western
Australia (IUCN, 2009)
The global population has not been quantified but Clements listed it as uncommon or
scarce (IUCN, 2009)
Given that so little is recorded on this species there is scant information to comment
satisfactorily on it historical status although – “Much of this species' habitat has been
cleared for agriculture, degraded by salinization, or destroyed during the construction
of water storage dams. It was feared that local extinctions would occur in the
fragmented habitat remnants as a result of fire or other random processes as it was
a sedentary species. However, it is now known to disperse more widely, and still
occurs over most of its former range.” (Garnett, 1992)
Given its apparent aversion for Human habitation it appears that its habitat has
shrunk in line with deforestation and land demands of an ever expanding human
population in the range it occupies as evidenced by the concerns of CALM
previously outlined.
Introduced Geographical Range:
Not applicable for this species as no feral populations are known to exist.
This species is not listed in J.L.Longs' "Introduced Birds of the World" - which is
the premier work on introduced avian species.
Kingston (2010) also states that there are no published records of the species ever
having been established in the wild in any part of the globe despite being a fairly
common aviary species.
Potential Distribution In Tasmania:
Using the Climatch program from the Bureau of Rural Science (DAFF) the natural
range of the Red-eared firetail finch was compared with that of Tasmania for a
possible correlation for the establishment of feral populations.
For the purposes of this Risk Analysis the geographical range for the Red-eared
firetail was taken from:
http://mapservices.iucnredlist.org/IUCN/mapper/index.html?ID_NO=149388
29 stations were utilised in the generation of the Climatch map and there were 6
scores that were >5 giving this species a Low-Moderate Climatch score of (6-9).
Fig. 1. Climate match results showing the potential geographical distribution of the
Red-eared firetail finch (Stagonopleura oculata) in Australia. (Source: Climatch http://adl.brs.gov.au:8080/Climatch/)
Diet & Feeding Behaviour:
In the wild was obtained for their natural food species in the wild and most authors
simply stated that they consume seeds and insects.
They feed in low vegetation close to the ground or on the ground itself. There is no
reference to this species consuming human feed crops; in fact they are recorded as
a species that shuns human habitation in any form.
As previously stated there is a lack of any grassland in Tasmania that could support
such a granivorous species.
In captivity their diet consists of a range of millet, panicum and plain canary seeds –
none of which are commercially grown in Tasmania.
Social Behaviour & Groupings:
Very little is available in print concerning the habits of this species.
From avicultural observation the species would appear to be highly territorial when
nesting and intolerant of members of its own species.
Outside the breeding season it is known to form small groups for feeding purposes
but it is unknown as to whether these groups remain together for any other
purposes.
Natural Predators or Disease:
Again information is scant but as a small Passerine I would image that they are a
common food source for larger avian and mammalian predators.
As Tasmania possesses a large number of avian predators – from the introduced
Kookaburra, numerous large Wattlebirds, the Noisy miner, the Butcherbird and
numerous Raptor the chances of this solitary species being able to avoid these
species is questionable.
Add to this the large number of feral cats that exist in most habitats within Tasmania
and this species would be at extreme risk in the unlikely event it should ever escape.
Perhaps even more damming than this is the lack of wild blood in the current aviary
bred population due to their isolation and subsequent aviary conditioning which
would make these birds easy prey for higher-order predators – a trait shared by all
finch species currently held in Tasmanian aviaries.
There were no recorded episodes of natural diseases that had, in the past, delimited
the wild population of this species.
Threat to Human Safety:
The Red-eared firetail finch is a small Passerine species which is not equipped to
cause any deleterious effects to members of the general public. A lack of
claws/talons, or a ripping beak and its diminutive size would render this improbable.
It is generally not equipped to cause any harm to humans.
In a previous submission to bring another member of the Stagonopleura genus into
Tasmania I consulted with most of Australia top avian veterinarians whom informed
me that they were not aware of any know zoonotic diseases present in Australian
aviary finches (or in particular in the Stagonopleura genus) that should preclude their
import into Tasmania and certainly none, in their opinion, that could be transmitted to
humans or endanger the Tasmanian Biodiversity. (Brown, Gellis, Walker & Harris.
pers.comm)
In the literature consulted there were no recorded adverse disease effects of Redeared firetail finches upon humans.
History as a Pest Species:
As previously outlined there is no precedence for this discussion given that the
species has never been intentionally released into any environment for the purposes
of colonisation.
In the wild I could find no reports of its foraging and feeding habits impinging upon
any forms of human agricultural land usage, in fact it prefers to shun contact with
human settlements.
Any accidental/intentional non-recorded releases must, given the lack of any
recorded sustainable wild populations, have also met with failure.
However, given its rarity and specific habitat conditions we doubt whether any
attempts have been made to introduce it elsewhere – a statement supported by the
available literature.
In order to even house this species in Tasmania an aviary would have to be custom
built to reflect the temperature and appearance of its natural range.
Subsequently it has zero history as a pest species.
As previously mentioned the authors consulted all state that, to their knowledge, no
wild populations of the Red-eared firetail finches existed outside of their natural
range.
It is not listed on the Global Invasive Species Database.
Potential Impact in Tasmania:
As a member of the Stagonopleura genus it has one close relative in the Tasmanian
bush in S.bella and, as previously outlined, should pose little threat to existing native
species re hybridisation (never recorded) or competition for resources.
The introduced Gold & Greenfinch exist in close proximity with human agricultural
land use and have benefited from that arrangement and spread accordingly as urban
expansion tends to force existing native species from that area and these two
resourceful Fringillid species have benefitted accordingly.
Releases of both these species were from wild-caught blood directly from Europe
and were not from aviary reared strains. In fact some authors suggest that these
wild-bloodlines contribute markedly to the success or failure of escapee populations
(Carrete & Tella, 2008).
With the adoption of European land use methods during the colonisation of Australia
and the subsequent introduction of numerous grass and weed species created the
perfect niche for these introduced species.
It should also be noted that the Beautiful firetail also occurs in areas with a heavy
compliment of both these Fringillid species with little obvious problems which
suggests a difference in feeding patterns.
In fact the author’s wild studies have demonstrated that it is the native Beautiful
firetail that has adapted to introduced weeds – especially in the case of winter grass,
Poa annua – whereas the Fringillid species both prefer the smooth Thistle and
Phalaris weeds thus reducing any perceived competition between the 2 groups of
finches.
In field observations at Lymington in the states south-west the author saw Firetails
sharing their nesting fruit tree with a nest of Goldfinches.
In captivity the Beautiful firetail prefers the three members of the Ehrharta family of
introduced South African grasses which tend to occur close to human habitation.
However, as previously stated by various authors the Red-eared firetail finch seeks
to distance itself from human habitation and, as such, would potentially subject itself
to the rigors of the harsh Tasmanian bush – complete with a full quote of larger
predatory avian species such as the Wattlebirds, Noisy miner, Butcherbird,
introduced Kookaburra and an assortment of Raptorial species.
Add to that feral cats and the Native cat and it would face a number of perils before it
could hope to become established.
Mr Oliver also lives in an area that is devoid of Beautiful firetails.
It should also be raised that the current aviary population of Red-eared firetail
finches has been in captivity for many generations which would dramatically alter
their chance for colonisation – unlike the previously mentioned releases of wildtrapped Gold & Greenfinches into Tasmania and into a custom-made ‘Europeanstyle’ environment.
Add to this the aggressive nature of S.bella and there is little chance for any aviary
escapee’s surviving long enough to contribute to a feral population.
Another defining factor is the high market value price of these finches which would
preclude them from ever being housed in anything but a situation with the highest
level of aviary security.
Further to this are recent observations on the Beautiful firetail where significant
changes in behaviour were recorded after only 2 generations in captivity which would
again prove deleterious for establishment in the wild (Pollard, in press).
Given the rarity of this species in captivity it would be even debatable that there are
enough of these finches in captivity in Australia to form the threshold for a viable
aviary population let alone an escapee wild population, as during the 2011 Australian
census of aviary finches undertaken by the National Finch & Softbill Association only
38 Red-eared firetail finches were recorded in Australia. (D.Pace pers.comm)
Based on this data alone it must be queried whether this species exists in sufficient
numbers that could even exert enough propagule pressure/number (introduction
effort) to even be considered at risk of establishing a feral population anywhere
within Australia let alone in Tasmania which is outside their preferred climatic zone.
Regretfully this aspect is also not a component of the Bomford model that is used to
determine this form of Risk Analysis concerning the establishment of species in the
wild yet is/should be a critical factor when deciding upon such specie that have been
in the closeted aviary population for decades.
Given that the other member of the Stagonopleura genus is a common aviary
species and held in large number and that this species - S.guttata- hails from a
similar climatic zone to S.bella and none have ever established escapee populations;
it would strongly suggest that there is negligible chance of S.oculata establishing any
feral population in this state. Given the long captive history of all 3 species and the
dearth of recorded hybrids between them in the available literature or in numerous
conversations with aviculturists holding these birds then that aspect should be
considered as inconsequential as a delimiting factor for the import of this species into
Tasmania.
As with all finch species in captivity their staple seed requirements are various millets
and panicums plus plain canary seed none of which are grown in Tasmania because
of the limited growth span afforded during our summer.
Again as for any finch species there is a lack of any such seeding
grasses/grasslands growing anywhere in Tasmania which would in itself prove a
limiting factor in the spread of any finch species.
Perhaps the strongest argument yet for allowing this species as an import is found in
the following passage:
“The mid-nineties saw the Western Australian Finch Society successfully apply to the
Department of Conservation and Land Management for the implementation of a
captive Red-eared firetail breeding program. Approximately 10 aviculturists were
permitted to take 20 pairs of Red-eared firetails and attempt to establish them in
captivity. Alan Middleton was primarily responsible for the trapping, acclimatisation,
and finally the distribution of the birds.
Whilst the aviculturists willing to dedicate the time and effort to the species achieved
some success, the majority of the members of the group failed dismally to keep the
birds alive let alone breed” (McCrae, 2007).
In light of this difficulty where birds failed to acclimate to captivity in their natural
climatic range and within their natural habitat few fears should be held about any
potential for environmental damage within Tasmania.
REFERENCES:
Books & Articles:
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http://gaiaresources.com.au/databases/dbd/speciesresults.php?speciesselect=Redeared%20Firetail&Submit=Submit
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