Sign Transects and SLIMS
What Other Information Can Be Gathered?
SLIMS also includes methods for surveying the herds of wild sheep and goats that constitute the snow leopard’s primary food source under natural conditions. From well concealed vantage points on a hill or other place with a good view, and using binoculars or ideally a spotting scope, the researcher counts the herds as they are grazing or resting on nearby mountain slopes or valleys. The herd’s location is recorded using a handheld GPS. Also recorded are the particular species present, group size, the age-class and sex of each individual, size of the area visible and other relevant habitat parameters such as type of vegetation or terrain present, the distance to the nearest escape cover, and whether livestock graziers use the same pasture and when. For more information download SLIMS Volume 2.
By enumerating the prey population, biologists can estimate the amount of food potentially available for snow leopards as well as other large predators. Another means of validating the number of snow leopards that may occupy a particular area is predator-prey modeling. As with sign transect surveys, it may be possible to monitor the prey’s population size and trend by conducting counts over successive or alternate years in the same place and time of year, of course using the same methods and observers with similar observational skills.
Information about the health of wild prey and local threats helps determine what conservation actions are needed to improve their number. For example, if the herds are not very abundant but the habitat is otherwise suitable for both prey and snow leopard, conservation efforts would focus on increasing the wild sheep or goat populations so that snow leopards can better survive without preying on domestic livestock.