A comparison of scat counts and camera-trapping as means of assessing Iberian lynx abundance

Rigorous cost-effective census methods are an essential part of managing wild animal populations, particularly if the involved species require continuous monitoring. In recent years, the range and size of the Iberian lynx ( Lynx pardinus ) population have increased notably as a result of conservation programs. Given this expansive scenario, monitoring Iberian lynx using camera-traps may become logistically and financially unfeasible. Here, we test whether or not scat counts are as efficient as camera-trapping in predicting lynx densities and compare the cost of these two approaches to lynx monitoring. We found a significant positive linear relationship between these two methods of assessing Iberian lynx abundance. Lynx abundance assessment by scat counting was six times less expensive than camera-trapping; there was no significant effect of the two study areas on the observed patterns (GLM F 1,7 = 45.81, P < 0.001). Our study shows that scat counting is a non-invasive cost-effective method that can provide reliable assessments of Iberian lynx abundance. However, if comparisons are to be made, censuses should be carried out (a) under as nearly identical conditions as possible and (b) in the same season. A number of different factors affect scat abundance, and in order to improve counts, it would be of great interest to evaluate the potential effect of the factors that cause scat estimates to vary.