Effects of free-flight activities on wildlife: a poorly understood issue in conservation

Abstract

Recreational activities may have negative effects on wildlife, but there are very few studies specifically on the effects of free-flight activities (i.e., hang-gliders, paragliders and their powered derivatives) on wildlife. We review the existing scientific studies on this issue in order to identify the gaps in knowledge at the taxonomic-group level in order to develop guidelines to minimize the impacts of recreational free-flight on wildlife. We found that studies mainly concerned the effects on four ungulate species (chamois, red deer, roe deer and Alpine ibex) and, to a lesser extent, on raptors such as the golden eagle and two vulture species (bearded vulture and cinereous vulture). The studies have generally been carried out in high mountain areas (e.g., the European Alps). Data show that free-flight activities create disturbances and have negative effects on wildlife, resulting in increased energy expenditure, reduction of feeding time, abandonment of feeding areas, reduced breeding output, loss of body condition, increased predation risk and harm from flight accidents. However, the lack of studies on many species and areas, along with the small number of long-term studies, prevents proper assessment of the current situation regarding the impact of this activity on wildlife. We provide recommendations to improve the regulation of this activity.