Population Monitoring

Camera-trapping and snow track counts

 

How do you know how many Amur leopards there are in the wild?

A critical component of Amur leopard conservation is monitoring of the population, which allows us to better understand population numbers and trends. Only through intensive monitoring can we determine whether our conservation actions are having a positive impact.

ALTA partner WCS has been engaged in monitoring the Amur leopard population since 1997, using two approaches – a traditional Russian methodology based on tracks in the snow, and more recently, more precise estimates using camera traps.

Tracking leopards

Historically Amur leopards and other wildlife in Russia have been surveyed in winter by counting tracks in the snow along an extensive series of designated routes. The track data are used to estimate relative abundance (tracks/km) and, with standardised approaches, population size. The first “snow-track leopard counts” were conducted in the 1970s by Dimitri Pikunov and Vladimir Abramov, and Pikunov and others have continued these counts to the present. These counts provide important information on the distribution and status of the entire Amur leopard population in Russia. Currently we attempt to repeat snow track counts every 3 years. The results of the most recent count in February-March 2007, financed by WWF-Russia and WCS, resulted in an estimated population of 27 to 32 leopards in SW Russia.

Snapping leopards

These traditional snow counts, while extremely useful, do not give precise information on densities of leopards, and cannot provide us other pieces of information vital to assessing viability of this subspecies, such as survival and recruitment rates. To obtain these data, we conduct camera-trap surveys. Camera trapping allows us to identify individual leopards by their unique spot patterns, and therefore we are able to monitor individual animals over many years. For instance, one leopard, captured in 1996 as part of a telemetry study, showed up in our camera traps in 2002 and 2003, but then disappeared.  Because we know that this leopard was an adult when first captured in 1996, we were able to determine that he lived a minimum of 10 years. Before WCS began camera-trapping in 2002, camera traps had never before been used for population monitoring in Russia. The method turned out to be very effective, and more than 300 photos of leopards have been taken since our first efforts in 2002.

Find out more about our Amur tiger camera trapping in Lazo

Putting the information together

Camera-trap data provide statistically rigorous estimates of population density and trends over time. Long-term data will also provide insight into turnover and mortality rates. Camera-trap monitoring results are maintained in a GIS (Geographic Information System) database that facilitates other analyses, such as determining correlations between leopard and ungulate densities, habitat types, land use, forest fires, proximity of settlements and roads, etc.

Camera-trap results between 2002 and 2011 as well as recent snow-track counts (2000, 2003, 2007) indicated a small but stable population of around 30 individuals in SW Primorye in Russia. A few individuals (probably no more than 5 leopards) live across the border in China. Cameras are placed along trails likely to be used by leopards (two cameras on eitehr side of trail at each sampling point) and as the pattern of rosettes is unique to each leopard, individual animals can be identified and counted.

The number of leopard photographs and the minimum number of leopards in the study area since 2002 can be seen in the table below:

YEAR  # Leopard Photos  Minimum # of Leopards
 2002-2003                   65                            9
      2004                   69                           13
      2005                  113                           14
      2006                   63                            9
      2007                   65                           14
      2008                   56                            8
      2009                  106                            9
      2010                   63                           12
      2011                  156                           17

The overall trend in leopard numbers is positive with 17 being seen in 2011 but the fluctuations over the years show there is sadly no steady upward trend in the study area. WCS used new camera in 2011 which are able to take picture in quick succession and they photographed two leopard cubs in camera traps for the first time ever. This means 15 adults were counted and it is likely that a lot of the leopards are transients and are unlikely to be present in 2012. It seems only a few leopards are permanent residents of the area who appear regularly in the monitoring.

Overall though the monitoring does indicate that there is robust reproduction and animals are dispersing in search of suitable habitat. Concerted efforts are therefore needed to ensure habitat improvement to increase prey base is a priority in both the Russia and China.

Snapping Amur tigers

Amur tiger numbers are also monitored and their numbers appear to be more stable with 3-4 adult tigers in the study area in all years except 2010 when two new females arrived. In 2011 the camera traps twice captured a litter of three cubs bringing the total number to 7 tigers. As with the leopards, the presence of cubs and transients indicates reproduction is good and this particular population appears to be sustaining itself.