Goodrich, J. M., I. V. Seryodkin, D. G. Miquelle, L. L. Kerley, H. B. Quigley, M. G. Hornocker.
2011. Tooth Breakage in Tigers: cause for conflict? Journal of Zoology. In press.
The definitive version is available at www.blackwell-synergy.com
Effects of Canine Breakage on Tiger Survival, Reproduction, and Human-Tiger
Conflict
John M. Goodrich1, Ivan V. Seryodkin2, Dale G. Miquelle1, Linda L. Kerley3, Howard B.
Quigley4 & Maurice G. Hornocker4
1 Wildlife Conservation Society, 2300 Southern Blvd, Bronx, New York, USA
2 Pacific Geographical Institute, Russian Academy of Science, Radio Street 7, Vladivostok, Russia
3 Zoological Society of London, Lygovaya 7, Lazo, Primorsky Region, Russia
4 Hornocker Wildlife Institute and Wildlife Conservation Society, 2023 Stadium Drive, Suite 1a, Bozeman,
Montana, USA
Abstract
Human-tiger conflict (HTC) fuels tiger population declines through retaliation killing by
local people and government-sanctioned removal of problem individuals. This may have
significant impacts on population persistence. In tigers and other large felids, broken
canines are often assumed to be an infirmity that leads to HTC, but peer-reviewed
literature does not support this. Thus, removal of animals with broken canines from the
wild may result in unnecessary mortality. We examined data from wild Amur tigers to
establish a baseline for degree of canine breakage in wild tigers not involved in conflict
(referred to as “research tigers”), test for sex and age-related patterns in canine breakage,
and estimate the impacts on survival and reproduction. We further compared canine
breakage in research tigers to that in tigers captured or killed in HTC situations (HTC;
“conflict tigers”). We detected no difference (P = 0.76) in percent of tigers with broken
canines between the two groups (24% in research tigers versus 27% in conflict tigers) and
no difference between sexes (P = 0.84), but the proportion of animals with broken
canines increased with age class (P < 0.001). We detected no impact of canine breakage
on survival or reproduction of research tigers and four research tigresses produced 1-3
litters each, despite 1-3 broken canines. Broken canines were considered a significant
health issue in 2 of 17 cases, resulting in depredation in 1 case. Our data support the
premise that broken canines do not usually represent a serious health issue and are
usually not related to HTC. The assumption that broken canines lead to HTC appears
invalid and may result in tigers being unnecessarily removed from the wild by managers.
Similar results have been found for lions and the trend may be true for other large cats
and carnivores as well.
Key words
Amur (Siberian) tiger, Panthera tigris altaica, tooth breakage, human-tiger conflict,
Russia.
Correspondence
Wildlife Conservation Society, Asia Program, 2300 Southern Blvd, Bronx, NY, 10460,
USA. Tel.: +1 (718) 220-1954. Email [email protected]
Introduction
Tigers (Panthera tigris) are critically endangered, with only about 3500
individuals left in the wild occupying 7% percent of their historical range (Sanderson et
al., 2006; Seidensticker, Gratwicke, & Shrestha, 2010). Their decline has been attributed
to habitat loss and human-caused mortality, the latter driven primarily by poaching to
supply black-market trade (Walston et al., 2010). However, human-tiger conflict (HTC)
fuels population declines through retaliation killing by local people and governmentsanctioned removal of problem individuals (reviewed in Goodrich, 2010; Inskip &
Zimmerman, 2008). Such human-caused mortality may have significant impacts on
population persistence (Chapron et al., 2008; Kenney et al., 1995).
As part of the Global Tiger Initiative, 13 tiger range states recently pledged to
double tiger populations by the next Year of the Tiger (Global Tiger Recovery Program,
2010). However, HTC will likely also increase with increased numbers of tigers
(Karanth & Gopal, 2005) and an expanding human population in Asia, so proactive plans
to manage HTC will be important to successful recovery. Many governments have
developed or are developing “tiger response teams” that are trained to capture tigers
involved in HTC situations, assess their condition, and make an appropriate decision as to
the fate of the tiger based largely on its physical condition, i.e., whether or not the animal
is fit to survive in the wild (Barlow et al., 2010; Goodrich et al., 2011; Gurung et al.,
2009). Accurate assessment of whether a tiger is fit or infirm is critical to avoid
unnecessarily removing animals from the wild.
Broken teeth, particularly canines, are often cited as infirmities that lead to
depredations by large felids on domestic animals and humans (e.g. Gurung et al., 2009;
Marker, 2003; Rabinowitz, 1986) and hence, broken canines may be considered a reason
to remove large felids from the wild. The idea that broken canines represent a significant
infirmity resulting in conflict probably stems in part from common sense, popular
literature that reports broken canines in man-eating tigers and lions (P. leo) (Corbett,
1955, 1957), and peer-reviewed literature providing strong evidence that damaged
dentitions resulted in depredations by the legendary man-eating lions of Tsavo (Neiburger
& Patterson, 2000, 2002). Broken canines are common in wild felids with 20-40% of
skulls examined in various studies having damaged dentition (Patterson, Neiburger, &
Kasiki, 2003; Van Valkenburg, 1988, 2009), but the occurrence of broken teeth was not
correlated with conflict in a study of lion dental condition (Patterson et al., 2003). No
such studies have been conducted for tigers, yet despite evidence to the contrary for lions,
broken canines are sometimes assumed to be a significant cause of depredations on
humans and domestic animals (Gurung et al., 2009), and managers may consider broken
teeth as a reason to remove conflict animals from the wild.
We used data on tooth breakage in wild Amur tigers in the Russian Far East to
examine the relationship between HTC and tooth breakage. We analyzed data on tooth
breakage in tigers captured as part of a long-term research project (hereafter referred to as
“research tigers”) in the Russian Far East (Miquelle et al., 2010a) to establish a baseline
for frequency of canine breakage in wild tigers and estimate the impacts of tooth
breakage on tiger health, survival, and reproduction. We compared canine breakage
between research tigers and tigers captured in HTC situations (hereafter referred to as
“conflict tigers”) to determine if tooth breakage could be implicated as a cause of HTC.
Methods
Research tigers were captured from 1992-2010 on and near the Sikhote-Alin
Biosphere Zapovednik (448469N, 1358489E), which is centrally located in the northsouth gradient of the geographic range of tigers in the Russian Far East (Miquelle et al.,
2010a). We collected data on conflict tigers from 1999-2010 (Goodrich et al., 2011)
throughout the range of Amur tigers in Russia, which is primarily confined to the Russian
Far East provinces (Krais) of Primorye and Khabarovsk (Miquelle et al., 1999). In 2005,
there were estimated to be <400 adult and subadult tigers in Russia (Miquelle, Pikunov &
Dunishenko, 2007), with about 95% occurring in the foothills and main ranges of the
Sikhote-Alin Mountains, the crest of which runs north–south through most of the tigers’
current range in Russia. The area consists of two Tiger Conservation Landscapes
(Sanderson et al., 2006) representing a zone where East Asian coniferous–deciduous
forests and the boreal forests merge, resulting in a mosaic of forest types (Miquelle et al.,
2010a). In contrast to most tiger habitat in Asia, the climate of Amur tiger range in
Russia is marked by cold, snowy winters that likely stress tigers and ultimately limits
their geographic distribution (Miquelle et al., 2010b). The climate is monsoonal, with
75–85% precipitation (650–800 mm in central Sikhote-Alin) occurring as rain between
April and November. Snow depth varies greatly by locale and year, but averages 22.6 cm
in mid-February (60-year mean) in the inland central Sikhote-Alin and only 13.7 cm on
the coast (data from Primorye Weather Bureau). However, heavy snowfalls, most
common in March, can have dramatic impacts on ungulate and tiger populations. The
January monthly mean temperature in Sikhote-Alin Biosphere Zapovednik (roughly the
geographic center of tiger range) is ‒22.6° C on the inland side of the central SikhoteAlin Mountains, but the Sea of Japan moderates temperatures and snow depths on the
coastal side of the range, when the January monthly mean is ‒12.4° C. The July monthly
mean temperature is 15° C on the coast and 18.4° C inland.
Research tigers were captured in Aldrich foot snares or darted from helicopter
and conflict tigers were captured or killed by a variety of means from 1992-2010
(Goodrich et al., 2001, 2011). Canine teeth were examined and usually photographed
and condition noted. We estimated age of tigers based on known birth dates of cubs born
to radio-collared tigers (Kerley et al., 2003), degree of tooth eruption, and/or degree of
tooth wear, gum recession, and staining (Goodrich et al., 2001), and placed in one of four
age classes: <4, 4-7, 7-10, and >10. Our analysis included only permanent teeth and only
broken canines with pulp exposure and hence underestimates overall tooth damage.
However, for live tigers, it was not always possible to examine all teeth before tigers
recovered from anesthesia and for dead tigers, frozen carcasses or limited access to some
carcasses hindered detailed examinations. For similar reasons, we were unable to
estimate the age of a few tigers.
To establish a baseline for canine breakage in wild Amur tigers not involved in
conflict, we calculated the percent of research tigers with one or more broken canines.
While some research tigers occasionally killed domestic animals, none were considered
conflict animals because: 1) they did not depredate repeatedly over short periods, 2) they
did not enter villages or farm yards to kill domestic animals, and 3) there depredations
did not require management action. In contrast, conflict tigers were captured after
repeated depredations resulted in a request by the government to capture the animal
(Goodrich et al., 2011). To determine if canine breakage was related to sex or age, we
compared the percent of animals with broken teeth between sexes and among the 4 age
classes. For individual tigers captured multiple times over several years, data were used
from only one capture per tiger selected at random. We examined the potential impact of
broken canines on survival of research tigers by comparing annual survival (van der
Toorn, 1997) and the mean age at death between resident (Goodrich et al., 2010) research
tigers with broken canines and those without. Non-resident subadult (i.e. dispersing)
animals were not included because dispersal-related mortality was nearly 100%
(Goodrich et al., 2008). None of these tigers had broken canines, so including these
animals with their low survival rates would have biased the test, reducing the chance of
detecting a difference in survival associated with canine breakage. Some tigers were
initially captured without any broken canines, but had broken canines in subsequent
captures. For survival analysis, we estimated the date on which a canine was broken as
the mean date between captures. Further, these animals were included in both groups and
survival rates assumed to be independent. Thus, while 24 tigers were included in the
survival analysis, the overall sample size was 27. Date of death was determined based on
radio-tracking data as described by Goodrich et al. (2008).
To determine if broken canines influenced reproductive rates, we compared
number of cubs produced per year (Kerley et al., 2003; Goodrich et al., 2010) between
tigers with broken canines and those without. In cases where litter size was unknown, but
radio-collared tigresses were known to be with cubs, litter sizes were estimated as the
mean number of cubs per litter (2.5; Kerley et al., 2003, 2005). Means were compared
using t-tests and frequency of tooth breakage using chi-square tests (Ambrose &
Ambrose, 1981).
To examine the relationship between canine breakage and conflict, we compared
data on proportion of tigers with broken canines between research tigers and conflict
tigers. We compared mean age of research tigers with that of conflict tigers because
degree of tooth breakage likely increases with age.
Results
We detected no difference in proportion of research and conflict tigers with
broken canines (χ2 = 0.09, d.f. = 1, P = 0.76); 24% of research tigers (n = 46) and 27% of
conflict tigers (n = 22) had broken canines (Table 1). We detected no difference in age
between research tigers (x̄ = 5.0 ± 3.5) and conflict tigers (x̄ = 5.3 ± 3.5; t = 0.43, d.f. =
61, P = 0.67). For both samples combined, we detected no difference between sexes in
proportion of animals with broken teeth (χ2 = 0.81, d.f. = 1, P = 0.84), but the proportion
of animals with broken canines increased with age class (χ2 = 33.8, d.f. = 3, P < 0.001;
Fig. 1). Two research tigers and 1 conflict tiger damaged canines as a result of capture.
Of these, 1 research tiger damaged a canine during capture and the tooth later broke at the
point of damage (Goodrich et al., 2001). The remaining 2 tigers displayed slab fractures
and chipping as a result of capture on canines that appeared to have been broken prior to
capture. However, all of these tigers had additional canines that had broken prior to
capture, so damage as a result of capture does not influence our results.
We detected no difference between estimated annual survival for tigers without
broken canines (0.82 ± 0.06) and those with broken canines (0.73 ± 0.11; z = 0.13, P =
0.89) (Table 1). The mean age at death was greater for tigers with broken canines (x̄ =
10.8 ± 3.0, n = 10) than for those without (x̄ = 7.6 ± 2.6, n = 10; t = -2.77, d.f. = 22, P =
0.01). We detected no difference in mean number of cubs born per year between research
tigresses with (x̄ = 1.2 ± 1.2, n = 9) and without (x̄ = 1.3 ± 0.6, n = 4) broken canines
(Table 1). Four research tigresses produced 1-3 litters each, despite 1-3 broken canines.
We found evidence suggesting that broken teeth were a serious health issue in 2
cases. The first was a conflict tiger who had 3 broken canines, but was also missing
several other teeth, including all of the premolars and the molar on the upper left side of
her mouth. The missing teeth had not broken, but fallen out, suggesting dental disease.
This tigress was emaciated when captured, likely due to difficulty eating frozen prey
because of missing teeth, and had killed several domestic animals in a town. The second
was a research tiger that had broken an upper canine at the gum line prior to capture. Part
of the break extended 3 cm into the skull, resulting in a hole packed with debris and prey
remains, resulting in infection. Despite being a large (200 kg) adult male (7 yrs old), this
animal’s home range was only 159 km2; whereas mean adult male home range size was
1,385 ± 539 km2 (Goodrich et al., 2010). We suspect that the tiger’s limited movements
were due to health issues associated with the broken tooth; however, 3 months after his
capture, we lost radio-contact with the tiger, likely because he was poached and his collar
destroyed (Goodrich et al., 2008). His body was not recovered.
Discussion
Van Valkenburg (2009) reported only 9% canine breakage in museum skulls of
tigers, which is considerably lower than 24-27% that we found. This may be due to
differences in mean age of specimens, i.e., tooth-wear data presented by Van Valkenburg
(2009) suggests a preponderance of young animals and very few old animals. Patterson
found 40% of lion skulls examined had damaged dentitions, but did not report canine
breakage specifically, and included unbroken teeth with pulp cavities exposed as
“damaged.” The proportion of tigers with broken teeth in our sample increased markedly
with age, as was found by Patterson et al. (2003) for lions. We believe that tooth damage
resulted in significant health issues in only two cases and resulted in depredation on
domestic animals in only one case. Otherwise, research tigers with broken canines did
not appear to have difficulty securing sufficient prey to survive and reproduce. There
was no difference in survival or reproduction between tigers with broken canines and
those without, and tigresses with 1-3 broken canines successfully raised cubs. We
believe that like lions, tigers have mechanisms to retard or prevent infection of broken
teeth with pulp exposures (Patterson et al. 2003). We may have failed to detect
differences due to small samples in some cases, particularly for difference in survival
between tigers with and without broken canines which was 9%. This difference was
likely due to the higher mean age of tigers with broken canines; however, sample sizes
were too small to calculate age-specific survival rates.
That there was no difference in age between research and conflict tigers
contradicts other studies. Conflict is often attributed to young animals that have not yet
established a home range or very old animals that have lost their home. Lions involved in
conflict are often younger than those not involved in conflict (Patterson et al., 2003;
Woodroffe & Frank, 2005). That adult age classes are well represented in our sample of
conflict tigers is alarming because it suggests that adult residents are equally vulnerable
to HTC-related mortality.
There was no significant difference in proportion of tigers with broken canines
between research and conflict tigers, and tooth damage was linked to conflict in only one
case. Patterson et al. (2003) found similar results for African lions and the pattern may
hold true for most large felids, which have similarly high tooth breakage rates (Van
Valkenburg, 1988, 2009). However, Rabinowitz (1986) found that 5 of 13 conflict
jaguars (P. onca) had broken canines, while all canines of 17 non-conflict animals were
intact, but insufficient data were presented to determine cause and effect.
Our data support the premise that broken canines in wild tigers are not usually an
impairment that significantly reduces an animal’s ability to kill wild prey, and in most
cases have no influence on whether a tiger kills domestic animals and humans. Managers
should not remove conflict tigers from the wild based on the presence of broken canines
alone. Further, in analyzing data on tiger dentition relative to conflict, researchers should
not assume that broken canines represent a serious health problem, but rather, should
examine broken teeth carefully for infection or other significant health issues caused by
the break. For example, for tigers and other big cats, broken canines are often listed as an
infirmity causing depredation on humans and domestic animals, but with no detail about
the injury, suggesting that the authors assumed that a broken canine is sufficient injury to
force an animal to prey on humans or livestock (e.g. Gurung et al., 2009; Marker, 2003;
Rabinowitz, 1986). Our data suggest that such an assumption is not valid for tigers and
similar results have been found for African lions (Patterson et al., 2003), and the same
may be true for other large felids. For all large cats, researchers should describe more
carefully dental damage and the reasons they believe it resulted in conflict (e.g. severe
infection associated with the break). Otherwise, managers are mislead into believing
broken canines are a serious issue leading to reduced body condition and eventual attacks
on domestic animals or humans, and may unnecessarily remove tigers or other large
carnivores from the wild.
Acknowledgements
Funding was provided by the Wildlife Conservation Society, National Fish and
Wildlife Foundation’s Save the Tiger Fund, 21st Century Tiger, U.S. Fish and Wildlife
Service Rhino and Tiger Conservation Fund, the Homeland Foundation, The Columbus
Zoo and Aquarium Conservation Fund, National Geographic Society, Exxon
Corporation, the Charles Engelhard Foundation, Disney Wildlife Fund, Turner
Foundation, Richard King Mellon, Avocet Charitable Lead Unitrust, Robertson
Foundation, Starr Foundation, Goldman Environmental Foundation, the Homeland Fund,
Denver Zoo, and numerous private donors. A. Khobitnev, E. Tsarapkin, B. Schleyer, N.
Rybin, A. Rybin, A. Kostirya, I. Seryodkin, V. Melnikov, A. Saphonov, V. Schukin, and
E. Gishko assisted with data collection. A. A. Astafiev and M. Gromyko, Y. Potikha, and
Y. Pimenova of Sikhote-Alin Biosphere Zapovednik , S. A. Zubtsov of Inspection Tiger,
and T.S. Aramiliev of the Primorye Wildlife Management Department provided logistical
and administrative support. The Russian Ministry of Natural Resources provided permits
for capture. John Seidensticker and an anonymous reviewer provided helpful comments
on a previous draft.
References
Ambrose, H. W., & Ambrose, K. P. (1981). A handbook of biological investigation.
Winston-Salem, North Carolina, USA: Hunter Textbook.
Barlow, A. C. D., Greenwood, C. J., Ahmad, I. U. & Smith, J. L. D. (2010). Use of an
action–selection framework for human–carnivore conflict in the Bangladesh
Sundarbans. Conserv. Biol. 24, 1338–1347.
Chapron, G., Miquelle, D. G., Goodrich, J. M., Legendre, S. & Clobert, J. (2008). The
impact of poaching versus prey depletion on tigers and other large solitary felids. J.
Appl. Ecol. 45,1667-1674.
Corbett, J. (1955). The temple tiger and more man-eaters of Kumaon. New York: Oxford
University Press.
Corbett, J. (1957). Man-eaters of India. New York: Oxford University Press.
Global Tiger Recovery Program. (2010). http://www.globaltigerinitiative.org/download/
St_ Petersburg/GTRP_Nov11_Final_Version_Eng.pdf.
Goodrich, J. M. (2010). Human-Tiger Conflict: a Review and Call for Comprehensive
Plans. Integ. Zool. 5, 297-308.
Goodrich, J. M., Kerley, L. L., Schleyer, B. O., Miquelle, D. G., Quigley, K. S.,
Smirnov, E. N., Nikolaev, I. G., Quigley, H. B. & Hornocker, M. G. (2001).
Capture and chemical anesthesia of Amur tigers. Wildl. Soc. Bull. 29, 533-542.
Goodrich, J. M., Kerley, L. L., Smirnov, E. N., Miquelle, D. G., McDonald, L.,
Quigley, H. B., Hornocker, M. G. & McDonald, T. (2008). Survival rates and
causes of mortality of Amur tigers on and near the Sikhote-Alin Biosphere
Zapovednik. J. Zool. 276, 323-329.
Goodrich J. M., Miquelle, D. G., Smirnov, E. N., Kerley, L. L., Quigley, H. B. &
Hornocker, M. G. (2010). Spatial structure of Amur (Siberian) tigers (Panthera
tigris altaica) on Sikhote-Alin Biosphere Zapovednik, Russia. J. Mamm. 91, 737748.
Goodrich, J. M., Seryodkin, I. V., Miquelle, D. G., & Beriznuk, S. I. (2011). Conflicts
Between Amur (Siberian) Tigers and humans in the Russian Far East. Biol.
Conserv. 144, 584-592.
Gurung, B., Smith, J. L. D., McDougal, C., Karki, J. B. & Barlow, A. (2009). Factors
associated with human-killing tigers in Chitwan National Park, Nepal. Biol.
Conserv. 141, 3069–3078.
Inskip, C., & Zimmermann, A. (2009). Human-felid conflict: a review of patterns and
priorities worldwide. Oryx 43,18–34.
Karanth, K. U. & Gopal, R. (2005). An ecology-based policy framework for human–tiger
coexistence in India. In People and wildlife: conflict or co-existence?: 373-387.
Woodruffe, R. & Thirgood, S. & Rabinowitz, A. (Eds). Cambridge: Cambridge
University Press.
Kenney, J. S., Smith, J. L. D., Starfield, A. M. & McDougal, C. W. (1995). The longterm effects of tiger poaching on population viability. Conserv. Biol. 9, 1127-1133.
Kerley, L. L., Goodrich, J. M., Miquelle, D. G., Smirnov, E. N., Nikolaev, I. G., Quigley,
H. B. & Hornocker, M. G. (2003). Reproductive parameters of wild female Amur
(Siberian) tigers (Panthera tigris altaica). J. Mamm. 84, 288-298.
Kerley, L. L., Goodrich, J. M., Nikolaev, I. G., Miquelle, D. G., Smirnov, E. N., Quigley,
H. B. & Hornocker, M. G. (2005). Reproductive parameters of wild female Amur
tigers. In Tigers of Sikhote-Alin Zapovednik: ecology and conservation: 61-69.
Miquelle, D. G., Smirnov, E. N. & Goodrich, J. M. (Eds.). Vladivostok, Russia: PSP. (in
Russian)
Marker, L. L., Dickman, A. J., Mills, M. G. L. & Macdonald, D. W. (2003). Aspects of
the management of cheetahs, Acinonyx jubatus jubatus, trapped on Namibian
farmlands. Biol. Conserv. 114, 401-412.
Miquelle, D. G., Goodrich, J. M., Kerley, L. L., Pikunov, D. G., Dunishenko, Yu. M.,
Aramiliev, V. V., Smirnov, E. N., Nikolaev, I. G., Salkina, G. P., Zhang, E.,
Seryodkin, I. V., Carroll, C., Gapanov, V. V., Fomenko, P. V., Kostyria, A. V.,
Murzin, A. A., Quigley, H. B. & Hornocker, M. G. (2010a). Science-Based
Conservation Of Amur Tigers In Russian Far East And Northeast China. In Tigers
of the world: the science, politics, and conservation of Panthera tigris, 2nd edition:
399-419. Tilson, R & Nyhus, P. (Eds). Oxford: Elsevier Limited.
Miquelle, D. G., Goodrich, J. M., Smirnov, E. N., Stephens, P. A., Zaumyslova, O. Yu.,
Chapron, G., Kerley, L., Murzin, A. A., Hornocker, M. G. & Quigley, H. B.
(2010b). The Amur tiger: a case study of living on the edge. In The biology and
conservation of wild felids: 325-339. Loveridge, A. J. & Macdonald, D. W. (Eds.).
Oxford: Oxford University Press.
Miquelle, D. G., Pikunov, D. G. & Dunishenko, Y. M. (2007). 2005 Amur tiger census.
Cat 1ews 46, 11–14.
Miquelle, D. G., Smirnov, E. N., Merrill, W. T., Myslenkov, A. E., Quigley, H. B.,
Hornocker, M. G. & Schleyer, B. (1999). A habitat protection plan for the Amur
tiger. In Riding the tiger: meeting the needs of people and wildlife in Asia: 273295. Seidensticker, J., Christie, S. & Jackson, P (Eds). Cambridge: Cambridge
University Press.
Neiburger, E. J., & Patterson, B. D. (2000). Man eating lions—a dental link. J. Am.
Assoc. .For. Den. 24, 1–3.
Neiburger, E. J. & Patterson, B.D. (2002). A forensic dental determination of serial
killings by three African lions. Gen. Den. 50, 40–42.
Patterson, B. D., Neiburger, E. J. & Kasiki, S. M. (2003). Tooth breakage and dental
disease as causes of carnivore-human conflicts. J. Mamm. 84, 190-196.
Rabinowitz, A. (1986). Jaguar predation on domestic livestock in Belize. Wildl. Soc.
Bull. 14, 170-174.
Sanderson, E., Forrest, J., Loucks, C., Ginsberg, J., Dinerstein, E., Seidensticker, J.,
Leimgruber, P., Songer, M., Heydlauff, A., O’Brien, T., Bryja, G., Klenzendorf, S.
& Wikramanayake, E. (2006). Setting priorities for the conservation and recovery
of wild tigers: 2005–2015. The Technical Assessment. Washington D.C.: WCS,
WWF, Smithsonian, NFWF-STF.
Seidensticker, J., Gratwicke, B. & Shrestha, M. (2010). How many wild tigers are there?
An estimate for 2008. In Tigers of the world: the science, politics, and conservation
of Panthera tigris, 2nd edition: 293-298. Tilson, R & Nyhus, P. (Eds). Oxford:
Elsevier Limited.
van der Toorn, J. (1997). Survival guide to survival rates. Marine Mamm.: Pub. Disp.
Res. 3, 27-38
Van Valkenburgh, B. (1988). Incidence of tooth break-age among large, predatory
mammals. Am. 1at. 131, 291–300.
Van Valkenburg, B. (2009). Costs of carnivory: tooth fracture in Pleistocene and recent
carnivorans. Biol. J. Linn. Soc. 96, 68–81.
Walston, J., Robinson, J. G., Bennett, E. L., Breitenmoser, U., da Fonseca, G. A. B.,
Goodrich, J., Gumal, M., Hunter, L., Johnson, A., Karanth, K. U., Leader-Williams,
N., MacKinnon, K., Miquelle, D., Pattanavibool, A., Poole, C., Rabinowitz, A.,
Smith, J. L. D., Stokes, E. J., Stuart, S., Vongkhamheng, C. & Wibisono, H. (2010).
Bringing the tiger back from the brink - the six percent solution. PLoS Biol. 8,
e1000485. doi:10.1371/journal.pbio.1000485.
Woodroffe, R. & Frank, L. G. (2005). Lethal control of African lions (Panthera leo):
local and regional population impacts. Anim. Cons. 8, 91-98.
Table 1 Percent canine breakage in research tigers versus conflict tigers and
reproductive and survival rates between research tigers with broken canines and those
without, 1992-2010, Russian Far East.
Research Tigers
Mean or
percent
SD
5.0
3.5
24%
Conflict tigers
n
22
22
mean
5.3
27%
SD
3.5
0.06
na
na
na
0.73
0.11
na
na
na
9
1.2
1.2
na
na
na
4
1.3
0.6
na
na
na
Age
canine breakage
n
45
46
survival rate w broken
canines
8
0.82
survival rate w/out
broken canines
19
reproduction rate w
broken canines
reproduction rate w/out
broken canines
List of Figures
Figure 1 Percent of broken teeth in 4 age classes for wild Amur tigers in the Russian Far
East, 1992-2010.