Landscape of risk to roe deer imposed by lynx and different human hunting tactics

Abstract

Predator efficiency depends on how hunting tactics relate to habitat characteristics. Different tactics such as ambush, stalking, and pursuit may lead to spatially heterogeneous distributions of predation risk. Studying how such a landscape of risk looks in a multi-predator setting has become topical in light of the re-colonization of apex predators in areas with extensive human harvesting. The human hunter is likely to adapt hunting tactics to increase encounter rate and hunting success, but is also limited by time constraints, light conditions, legislation, tradition, and/or skills. The extent to which hunters vary tactics resulting in a spatial pattern of risk to ungulate prey has never been quantified. By comparing habitat characteristics between kill sites and sites used by GPS-marked roe deer, we quantified the landscape of risk as experienced by roe deer (Capreolus capreolus) exposed to predation by both Eurasian lynx (Lynx lynx) and humans using different hunting tactics in southeastern Norway. Lynx killed roe deer in denser habitat than roe deer used on average, while humans killed most roe deer in open terrain. However, humans used multiple hunting tactics, and habitat characteristics varied predictably between drive hunts conducted with rifle versus shotgun, and between stalking versus “sit and wait” hunts with a rifle. Vegetation density was higher where roe deer were shot during drive hunts with a shotgun and during stalking than when shot during drive hunting with a rifle or during “sit and wait” hunts. Shooting distance was shortest for drive hunts with a shotgun, similar for drive hunts with a rifle and stalking, and considerably longer during “sit and wait” hunting. Managers therefore have the possibility to create different risk landscapes by restricting types of weapons and types of hunting tactic allowed, also in combination with the duration of the hunting season.