Estimating abundance and density of Amur tigers along the Sino- Russian border

As an apex predator the Amur tiger(Panthera tigris altaica)could play a pivotal role in maintaining the integ­rity of forest ecosystems in Northeast Asia.Due to habitat loss and harvest over the past century,tigers rapidly declined in China and are now restricted to the Russian Far East and bordering habitat in nearby China.To fa­cilitate restoration of the tiger in its historical range,reliable estimates of population size are essential to assess effectiveness of conservation interventions.Here we used camera trap data collected in Hunchun National Na­ture Reserve from April to June 2013 and 2014 to estimate tiger density and abundance using both maximum likelihood and Bayesian spatially explicit capture-recapture(SECR)methods.A minimum of 8 individuals were detected in both sample periods and the documentation of marking behavior and reproduction suggests the presence of a resident population.Using Bayesian SECR modeling within the 11400 km2 state space,den­sity estimates were 0.33 and 0.40 individuals/100 km^(2) in 2013 and 2014,respectively,corresponding to an es­timated abundance of 38 and 45 animals for this transboundary Sino-Russian population.In a maximum likeli­hood framework,we estimated densities of 0.30 and 0.24 individuals/100 km^(2) corresponding to abundances of 34 and 27,in 2013 and 2014,respectively.These density estimates are comparable to other published estimates for resident Amur tiger populations in the Russian Far East.This study reveals promising signs of tiger recovery in Northeast China,and demonstrates the importance of connectivity between the Russian and Chinese popula­tions for recovering tigers in Northeast China.

Social structure and space use of Amur tigers(Panthera tigris altaica)in Southern Russian Far East based on GPS telemetry data

To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye,Russian Far East.Fixed kernel estimates of male home ranges were larger than those of female home ranges(P<0.05[mean 95%fixed kernel♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further north.Low overlap of adjacent home ranges suggested that females retained exclusive territories.Real core areas of females overlapped only slightly,and remained stable over multiple years.The home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of territoriality.Nonetheless,real core areas of males did not overlap,suggesting some spatial separation.In comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards males.We believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for mates.Continued monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis.

Population dynamics of Amur tigers(Panthera tigris altaica)in Sikhote-Alin Biosphere Zapovednik:1966–2012

In 2010,the world’s tiger(Panthera tigris)range countries agreed to the goal of doubling tiger numbers over 12 years,but whether such an increase is biologically feasible has not been assessed.Long-term monitoring of tigers in Sikhote-Alin Biosphere Zapovednik(SABZ),Russia provided an opportunity to determine growth rates of a recovering population.A 41-year growth phase was followed by a rapid decline in tiger numbers.Annual growth rates during the growth phase averaged 4.6%,beginning near 10%in the earliest years but quickly dropping below 5%.Sex ratio(females per male)mirrored growth rates,declining as population size increased.The rapid decline from 2009 to 2012 appeared to be tied to multiple factors,including poaching,severe winters and disease.Reproductive indicators of this population are similar to those of Bengal tiger populations,suggesting that growth rates may be similar.These results suggest that,first,tiger populations likely in general grow slowly:3–5%yearly increases are realistic and larger growth rates are likely only when populations are highly depressed,mortality rates are low and prey populations are high relative to numbers of adult females.Second,while more research is needed,it should not be assumed that tiger populations with high prey densities will necessarily grow more quickly than populations with low prey densities.Third,while growth is slow,decline can be rapid.Fourth,because declines can happen so quickly,there is a constant need to monitor populations and be ready to respond with appropriate and timely conservation interventions if tiger populations are to remain secure.Finally,an average annual growth rate across all tiger populations of 6%,required to reach the Global Tiger Initiative’s goal of doubling tiger numbers in 12 years,is a noble but unlikely scenario.

A comparison of reproductive parameters of female Amur tigers(Panthera tigris altaica)in the wild and captivity

A healthy population of captive Amur tigers might assist recovery of the wild population in Northeast China if individuals were properly prepared and considered suitable for release in the wild.We analyzed the breeding records of 68 female Amur tigers from 1995 to 2010 in the Hengdaohezi Felid Breeding Center of China and compared the reproductive parameters of this population to wild female Amur tigers.We found that the reproductive parameters of the captive population(the age of first parturition,length of gestation and litter survival rate)were not significantly different from those of wild Amur tigers.Differences in birth date and litter size between wild and captive populations may be caused by management protocols for the captive population or insufficient field data from the wild population.Reproductive parameters of females giving birth after losing a litter were similar to parameters of females that did not lose a litter,except for birth date.These results provide no indication of major problems in using captive females for a breeding program for release of cubs into the wild,but additional information is still needed to assess their suitability.

Estimation of body weight in captive Amur tigers(Panthera tigris altaica)

So far,there has been no safe and convenient method to weigh the largefierce animals,like Amur tigers.To address this problem,we built models to predict the body weight of Amur tigers based on the fact that body weight is proportional to body measurements or age.Using the method of body measurements,we extracted the body measurements from 4 different kinds of the lateral body image of tigers,that is,total lateral image,central lateral image,ellipsefitting image,and rectanglefitting image,and then we respectively used artificial neural network(ANN)and power regression model to analyze the predictive relationships between body weight and body measurements.Our results demonstrated that,among all ANN models,the model built with rectanglefitting image had the smallest mean square error.Comparatively,we screened power regression models which had the smallest Akakai information criteria(AIC).In addition,using the method of age,wefitted nonlinear regression models for the relationship between body weight and age and found that,for male tigers,logistic model had the smallest AIC.For female tigers,Gompertz model had the smallest AIC.Consequently,this study could be applied to estimate body weight of captive,or even wild,Amur tigers safely and conveniently,helping to monitor individual health and growth of the Amur tiger populations.

Identifying ecological corridors for Amur tigers(Panthera tigris altaica)and Amur leopards(Panthera pardus orientalis)

The rapid explosion of human populations and the associated development of human-dominated landscapes have drastically reduced and fragmented habitat for tigers(Panthera tigris)and leopards(Panthera pardus)across Asia,resulting in multiple small populations.However,Amur tiger(Panthera tigris altaica)habitat in Russia has remained largely interconnected,except for a break between tigers in southwest Primorye and the southern Sikhote-Alin Mountains.This habitat patch in southwest Primorye also retains the last population of Amur leopards(Panthera pardus orientalis).Genetic differentiation of tigers in southwest Primorye and the Sikhote-Alin Mountains along with survey data suggest that habitat fragmentation is limiting movement of tigers and leopards across the Razdolnaya River basin.We looked at historical and recent survey data on tigers and leopards and mapped existing cover types to examine land-use patterns of both large felids and humans in the development strip along the Razdolnaya River.We then used least-cost distance analyses to identify the most effective potential corridor to retain connectivity for large felids between Land of the Leopard National Park and Ussuriskii Zapovednik(Reserve).We identified a single potential corridor that still exists with a total distance of 62.5 km from Land of the Leopard National Park to Ussuriskii Zapovednik,mostly(93%)through forested habitat.We recommend formal recognition of a Razdolnaya ecological corridor and provide specific recommendations for each of 3 proposed management sections.

Behavior observation of Amur tiger (Panthera tigris altaica) in captivity

The various behaviors of four Amur tigers in captivity were investigated in March from 1998 to 2001 in Harbin Zoo. The results showed that the behavior could be divided into 5 major types: moving, resting, sleeping, eating and other behaviors (including drinking, urinating, grooming, playing, standing). Of all behavioral models, sleeping and moving behaviors alone accounted for 75.18% and were two major behavioral models of all behaviors. Resting, eating and other behaviors accounted for 24.82%. Apart from eating, one male and two female individuals have similar peak periods of 4 major behaviors (one peak period in the daytime, and one peak period at night), similar to that of wild Amur tiger. However, one female individual have two clear peak periods at night.

Risks involved in fecal DNA-based genotyping of microsatellite loci in the Amur tiger Panthera tigris altaica:a pilot study

In modern wildlife ecological research,feces is the most common non-invasive source of DNA obtained in the field and polymerase chain reaction(PCR) technology based on microsatellite markers is used to mine genetic information contained within.This is especially the case for endangered species.However,there are risks associated with this genotyping method because of the poor quality of fecal DNA.In this study,we assessed genotyping risk across 12 microsatellite loci commonly used in previous tiger studies using blood and fecal DNA from captive Amur tigers(Panthera tigris altaica).To begin,we developed an index termed the accumulated matching rate of genotypes(R)between positive DNA(blood samples) and fecal DNA to explore the correct genotyping probability of a certain microsatellite locus.We found that different microsatelliteloci had different genotyping risks and required different PCR amplification protocols.The genotyping errors we detected altered population genetic parameters and potentially impact subsequent analyses.Based on these findings,we recommend that:(1) four loci(E7,Fca094,Pti007 and Pti010) of 12 loci are not suitable for Amur tiger genetic research because of a low Rand difficulty reaching a stable status;(2) the Rof the 12 microsatellite loci plateaued differently,and considering limited budgets,amplification times of some loci could be increased when using fecal samples; and(3) future genetic analysis of wild Amur tigers should be corrected by genotyping error rates(1-R).

Genetic structure of the Amur tiger(Panthera tigris altaica)population:Are tigers in Sikhote-Alin and southwest Primorye truly isolated?

We used molecular genetic analyses to noninvasively identify individual Amur tigers and define subpopulations of tigers in the Russian Far East.We identified 63 individuals after genotyping 256 feces,7 hair and 11 blood samples collected within southern,central and northern Sikhote-Alin,as well as Southwest Primorye.Analysis of nuclear DNA at 9 microsatellite loci demonstrated greater genetic similarity between animals from southern and northern Sikhote-Alin(some 500 km apart)than between animals from Ussuriskii State Nature Reserve and Southwest Primorye(less than 10 km apart at their nearest point),suggesting that a true barrier exists preventing movements of tigers between Southwest Primorye and the southern Sikhote-Alin Mountains.

A comparison of food habits and prey preference of Amur tiger(Panthera tigris altaica)at three sites in the Russian Far East

Prey availability is one of the principal drivers of tiger distribution and abundance.Therefore,formulating effective conservation strategies requires a clear understanding of tiger diet.We used scat analysis in combination with data on the abundance of several prey species to estimate Amur tiger diet and preference at 3 sites in the Russian Far East.We also examined the effect of pseudoreplication on estimates of tiger diet.We collected 770 scats across the 3 sites.Similar to previous studies,we found that tigers primarily preyed on medium to large ungulates,with wild boar,roe,sika and red deer collectively comprising 86.7%of total biomass consumed on average.According to Jacobs’index,tigers preferred wild boar,and avoided sika deer.Variation in preference indices derived from these scat analyses compared to indices derived from kill data appear to be due to adjustments in biomass intake when sex–age of a killed individual is known:a component missing from scat data.Pseudoreplication(multiple samples collected from a single kill site)also skewed results derived from scat analyses.Scat analysis still appears useful in providing insight into the diets of carnivores when the full spectrum of prey species needs to be identified,or when sample sizes from kill data are not sufficient.When sample sizes of kill data are large(as is now possible with GPS-collared animals),kill data adjusted by sex–age categories probably provides the most accurate estimates of prey biomass composition.Our results provide further confirmation of the centrality of medium ungulates,in particular wild boar,to Amur tiger diet,and suggest that the protection of this group of species is critical to Amur tiger conservation.

Amur tiger stripes:individual identification based on deep convolutional neural network

The automatic individual identification of Amur tigers(Panthera tigris altaica)is important for population monitoring and making effective conservation strategies.Most existing research primarily relies on manual identifi-cation,which does not scale well to large datasets.In this paper,the deep convolution neural networks algorithm is constructed to implement the automatic individual identification for large numbers of Amur tiger images.The experimental data were obtained from 40 Amur tigers in Tieling Guaipo Tiger Park,China.The number of images collected from each tiger was approximately 200,and a total of 8277 images were obtained.The experiments were carried out on both the left and right side of body.Our results suggested that the recognition accuracy rate of left and right sides are 90.48%and 93.5%,respectively.The accuracy of our network has achieved the similar level compared to other state of the art networks like LeNet,ResNet34,and ZF_Net.The running time is much shorter than that of other networks.Consequently,this study can provide a new approach on automatic individual identification technology in the case of the Amur tiger.

A comparison of food habits and prey preferences of Amur tiger(Panthera tigris altaica)at the southwest Primorskii Krai in Russia and Hunchun in China

A small,isolated Amur tiger population ranges across the southwest Primorskii Krai region in Russia and Hunchun region in China.Many individuals,with“dual nationality,”cross the border frequently.Formulating effective conservation strategies requires a clear understanding of tiger food requirements in both countries.While the diets of tigers ranging in Russia is clearly understood,little is known of the tigers’feeding habits in China..We used scat analysis combined with data on the abundance of 4 prey species to examine Amur tiger diet and prey preferences in Hunchun.We examined 53 tiger scat samples from 2011 to 2016 and found that tigers preyed on 12 species(11 species in winter),4 of which were domestic animals with 33.58%biomass contribution;this was the first record of Amur tigers eating lynx in this area.Tigers showed a strong preference for wild boar(Jacobs index:+0.849),which were also the most frequently consumed prey,and a strong avoidance of roe deer(Jacobs index:–0.693).On the Russian side,domestic animals(just dog)were rarely found in tiger scat,and tigers did not show strong avoidance of roe deer,but of sika deer.We also found red deer footprints during winter surveys and that tigers ate red deer on the Chinese side,while there was no record of red deer feeding on the Russian side.Reducing or eliminating human disturbance,such as grazing,is essential to recovering tiger prey and habitat in this area and the Sino–Russian joint ungulate annual survey is indispensable for prey estimates of this small,isolated Amur tiger population.

Indicators of success for smart law enforcement in protected areas:A case study for Russian Amur tiger(Panthera tigris altaica)reserves

Although considerable conservation resources have been committed to develop and use law enforcement monitoring and management tools such as SMART,measures of success are ill-defined and,to date,few reports detail results post-implementation.Here,we present 4 case studies from protected areas with Amur tigers(Panthera tigris altaica)in Russia,in which indicators of success were defined and evaluated at each.The ultimate goal was an increase in tiger numbers to 1 individual/100 km^(2)at each site.We predicted that improvements in law enforcement effectiveness would be followed by increases in prey numbers and,subsequently,tiger numbers.We used short-term and long-term indicators of success,including:(i)patrol team effort and effectiveness;(ii)catch per unit effort indicators(to measure reductions in threats);and(iii)changes in target species numbers.In addition to implementing a monitoring system,we focused on improving law enforcement management using an adaptive management process.Over 4 years,we noted clear increases in patrol effort and a partial reduction in threats.Although we did not detect clear trends in ungulate numbers,tiger populations remained stable or increased,suggesting that poaching of tigers may be more limiting than prey depletion.Increased effectiveness is needed before a clear reduction in threats can be noted,and more time is needed before detecting responses in target populations.Nonetheless,delineation of concrete goals and indicators of success provide a means of evaluating progress and weaknesses.Such monitoring should be a central component of law enforcement strategies for protected areas.

Amur tiger conservation education program:A pilot study on program effectiveness

Anthropogenic impacts are the primary threats to Amur tigers(Panthera tigris altaica)and their habitat.Villagers living in proximity to tigers tend to view them negatively and,often,as a source of revenue on black markets.We aim to reduce human–tiger conflict by working with young students of Ternei County in the heart of tiger habitat in Primorskii Krai(Province).To inform and influence Ternei County’s future decision-makers,we developed“Safe Conduct”,a year-long education program held in 6 villages,culminating in a multi-school conference.We tested the efficacy of Safe Conduct as a potential model for tiger conservation educational programs.We measured levels of student knowledge about tiger ecology,their attitude towards tigers,and their willingness to engage in tiger conservation activites prior to,immediately after and 6 months following the completion of our program.Results supported the fundamental premise of Safe Conduct that knowledge and attitude towards tigers are correlated.Knowledge of tiger ecology and attitude towards tigers increased by the project’s completion;both remained high after 6 months.However,commitment to participation in conservation efforts rose temporarily post-program and then dropped.Results varied by village.We recommend that the reasons for the high performance measures of students in 2 villages be investigated,and that lessons learned be applied to villages that underperformed.Safe Conduct represents a potential model for environmental education programs in Ternei County and elsewhere to educate future generations,to eventually develop a strong commitment to Amur tiger conservation at the community level.

The development and application of a multiplex short tandem repeat(STR)system for identifying subspecies,individuals and sex in tigers

Poaching and trans-boundary trafficking of tigers and body parts are threatening the world’s last remaining wild tigers.Development of an efficient molecular genetic assay for tracing the origins of confiscated specimens will assist in law enforcement and wildlife forensics for this iconic flagship species.We developed a multiplex genotyping system“tigrisPlex”to simultaneously assess 22 short tandem repeat(STR,or microsatellite)loci and a gender-identifying SRY gene,all amplified in 4 reactions using as little as 1 ng of template DNA.With DNA samples used for between-run calibration,the system generates STR genotypes that are directly compatible with voucher tiger subspecies genetic profiles,hence making it possible to identify subspecies via bi-parentally inherited markers.We applied“tigrisPlex”to 12 confiscated specimens from Russia and identified 6 individuals(3 females and 3 males),each represented by duplicated samples and all designated as Amur tigers(Panthera tigris altaica)with high confidence.This STR multiplex system can serve as an effective and versatile approach for genetic profiling of both wild and captive tigers as well as confiscated tiger products,fulfilling various conservation needs for identifying the origins of tiger samples.

Addressing the impact of canine distemper spreading on an isolated tiger population in northeast Asia

The continuation of the isolated Amur tiger(Panthera tigris altaica)population living along the China-Russia border is facing serious challenges due to factors such as its small size(including 38 individuals)and canine distemper virus(CDV).We use a population viability analysis metamodel,which consists of a traditional individual-based demographic model linked to an epidemiological model,to assess options for controlling the impact of negative factors through domestic dog management in protected areas,increasing connectivity to the neighboring large population(including more than 400 individuals),and habitat expansion.Without intervention,under inbreeding depression of 3.14,6.29,and 12.26 lethal equivalents,our metamodel predicted the extinction within 100 years is 64.4%,90.6%,and 99.8%,respectively.In addition,the simulation results showed that dog management or habitat expansion independently will not ensure tiger population viability for the next 100 years,and connectivity to the neighboring population would only keep the population size from rapidly declining.However,when the above three conservation scenarios are combined,even at the highest level of 12.26 lethal equivalents inbreeding depression,population size will not decline and the probability of extinction will be<5.8%.Our findings highlight that protecting the Amur tiger necessitates a multifaceted synergistic effort.Our key management recommendations for this population underline the importance of reducing CDV threats and expanding tiger occupancy to its former range in China,but re-establishing habitat connectivity to the neighboring population is an important long-term objective.