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

Abstract

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 11 400 km(2) 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.

Relationships between humans and ungulate prey shape Amur tiger occurrence in a core protected area along the Sino‐Russian border

“…We used quantile regression because occupancy may only be expected to positively correlate to density at high levels of occupancy, that is, a triangular wedge‐shaped relationship between occupancy and abundance may be expected (Boyce et al, ). Density data were obtained from previous SCR modeling at each camera stations in the same area (Xiao et al, ), and the occupancy probability data were obtained from our occupancy prediction above at each camera stations. All analysis conducted in R package “quantreg” (Koenker, ).…”

“…To test for temporal overlap between tigers, prey, and livestock, we applied kernel density estimation to estimate the daily temporal pattern of activity for tigers, three ungulate species as well as human and cattle activities in forest in order to measure the overlap (Linkie & Ridout, ; Ridout & Linkie, ) and interaction. Finally, because occupancy is not necessarily linearly related to density (Kéry & Royle, ; Steenweg, Hebblewhite, Whittington, Mckelvey, & Lukacs, ), we tested the relationship between tiger occupancy and a previously published spatial model of density developed from spatially explicit capture–recapture (SCR) model within Hunchun Nature Reserve (Xiao et al, ).…”

Camera-trap monitoring of Amur Tiger (Panthera tigris altaica) in southwest Primorsky Krai, 2013–2016: preliminary results

“…Further expansion of both Amur tiger and leopard populations in southwest Primorsky Krai is unlikely since they currently occur in all suitable habitat, and further expansion is limited by surrounding agricultural and infrastructure development. Thus the contiguous Hunchun -Wangqing area of Jilin Province, China, which has large patches of suitable habitat, represents the best opportunity for recolonization and expansion of both large felid populations (Hebblewhite et al, 2012;Wang et al, 2016). Over the past decade the number of Amur tiger records in China, including breeding females, has been increasing (Xiao, 2015;Wang et al, 2016).…”

“…Thus the contiguous Hunchun -Wangqing area of Jilin Province, China, which has large patches of suitable habitat, represents the best opportunity for recolonization and expansion of both large felid populations (Hebblewhite et al, 2012;Wang et al, 2016). Over the past decade the number of Amur tiger records in China, including breeding females, has been increasing (Xiao, 2015;Wang et al, 2016). However, the future of tiger recovery in China still heavily depends on the southwest Primorye core population, as evidenced by the fact that most tigers recorded in China occur in close proximity to the international border (Wang et al, 2016).…”

“…Over the past decade the number of Amur tiger records in China, including breeding females, has been increasing (Xiao, 2015;Wang et al, 2016). However, the future of tiger recovery in China still heavily depends on the southwest Primorye core population, as evidenced by the fact that most tigers recorded in China occur in close proximity to the international border (Wang et al, 2016).…”