ESTIMATION OF THE NUMBERS OF THE FAR EASTERN LEOPARD (PANTHERA PARDUS) IN RUSSIA
The Far Eastern leopard, Panthera pardus orientalis, is one of the rarest subspecies of large cats in the world. Its numbers used to be estimated at 25–50 individuals. New methods of research using automatic cameras and molecular-genetic diagnostics failed to provide exhaustive information as well. Our work was carried out in 2011–2013 in the Southwest of the Primorsky Territory: from Razdolnaya River in the northeast to the border with North Korea in the south and China in the southwest. We chose a model area of 503 km2, where we installed a network of 41 pairs of Reconyx Rapidfire RC60, HC500, HC600 photo traps, high-speed automatic digital cameras with infrared motion sensors and infrared illumination, this allowing to obtain 1 frame per second. Information was removed from the photo traps once in four months. Two methods were used to survey the leopard population: direct extrapolation of the number of registered leopards during the year over the model area across the subspecies’ entire distribution area; and a modified method of Capture program utilized to determine the population density, which is also based on the principle of re-catching, taking into account the spatial relationships between animal registrations (Space Capture-Recapture, SECR) when using SPACECAP program. An “effective trapping area” was determined for correct extrapolations, one designed as a variant of half the average distance between two re–captures (1/2MMDM). This allowed us to obtain a buffer zone with a width of 5.66 km. The “effective trapping area” amounted to 1023 km2. Apparently unsuitable habitats were exclud from this area. In 377 pictures obtained with photo traps we identified 27 leopards, 10 of them males, 10 females, 7 individuals remained unsexed, while 10 individuals unidentified. Extrapolating these data to the entire territory taken up by potential leopard habitats in the Russian Far East, i.e. over an area of 3502 km2, allows us to conclude that the numbers of leopards total about 96–100 individuals, of which about 60 animals are resident and 35–40 are young, nomadic individuals. However, given the previous counts of leopard numbers, traces of which were found in an area of 2.233 km2, the overall estimate of the population is likely to be lower and will be about 60–65 leopards.