Effects of ranger stations on predator and prey distribution and abundance in an Iranian steppe landscape

Abstract

Ranger stations are essential to combat poaching in protected areas and the distance from ranger stations is sometimes used as a proxy for poaching levels and law enforcement intensity. However, the influence of the spatial distribution of ranger stations on wildlife abundance and population structure has rarely been investigated. We evaluated the abundance and distribution of urial sheep Ovis vignei and Persian leopard Panthera pardus saxicolor in the steppe of Golestan National Park in northeastern Iran. The spatial distribution of these species in regard to anthropogenic (distances to ranger stations, villages and park border) and environmental variables (distance to water resources, average slope and normalized difference vegetation index) was assessed using systematic line transect sampling (186 km) and camera trapping (1150 trap nights). The studied steppe area is divided into three management zones differing in the number of ranger stations and their position with respect to park boundaries. The results of multivariate analyses highlighted that the distance to ranger stations was negatively related to the size and density of urial clusters and the most important variable in explaining urial distribution. Moreover, the distance to park borders influenced urial cluster density. Leopard abundance was positively associated with urial density but was less affected by the other variables tested. We found urial densities in the three management zones to range from 0.15 +/- se 0.09 individuals km(-2) (zone with just one station outside the park) to 21.77 +/- se 7.92 individuals km(-2) (zone with three stations). Taking into account these results and historical data on ungulate abundance and distribution in these management zones, we conclude that law enforcement from ranger stations has shaped current patterns of ungulate distribution. These results confirm that a good coverage (both numbers and locations) of ranger stations is of central importance for the management of protected areas.