Estimating red deer population size using vantage point counts at baited sites

Accurate estimates of population size are central to the management and conservation of wild ungulates. Counting animals from vantage points of baited sites is a method that is traditionally used in Europe to obtain abundance estimates of wild ungulates, but its reliability in forested landscapes is contested. We assessed the accuracy of vantage point counts (VPCs) for estimating population size in red deer (Cervus elaphus) at De Hoge Veluwe National Park, a fenced, partially forested game reserve in the Netherlands. We compared estimates from duplicated VPCs for 1977–2010 with population sizes reconstructed from cohort analyses of age-specific mortality records, including and excluding supplementation with vehicular direct counts (VDCs) and field knowledge on herd composition and herd size from game wardens. Estimates from VPCs supplemented with VDCs matched the reconstructed population size well for 2001–2010. In addition, estimates based on ≥1 VPC site/11 km² provided representative estimates of the reconstructed population size in that period. Simultaneous VPCs at multiple baited sites can yield precise population estimates for red deer in forests.