EFFECTS OF FORESTRY AND OTHER LAND-USE PRACTICES ON THE CONSERVATION OF CINEREOUS VULTURES

Abstract

Managing forests to meet both production and conservation goals is a growing challenge around the world, particularly as forest areas devoid of human intervention continue to shrink in area. There is a general lack of information about the response of long-lived vertebrates to silvicultural treatments due to the difficulty of carrying out long-term studies that can disentangle the effects of forestry from other factors influencing the distribution and numbers of large organisms. We examined the responses of the Cinereous Vulture, Aegypius monachus, to two divergent forestry practices in two colonies where ∼10% of the European population breeds: (1) long-term exploitation of mature forest in high mountains (highland colony), and (2) clear-cutting and regeneration in lower altitude mountain areas (lowland colony). Distribution patterns of Cinereous Vultures were determined mainly by forestry and human-related activities, as well as by orographic variables, whereas forest structure had a lesser influence. Ecological factors such as orography and forest structure had a greater influence in the distribution and abundance of vultures in the highland area, whereas the influence of variables associated with human disturbance was stronger in the lowland area. Vultures in the lowland area consistently selected areas with a low incidence of forestry activity to breed. A major fraction of the variability of breeding success was not explained by the factors considered, although human-caused disturbance and rainfall during the nestling period had negative effects on breeding success in the lowland colony. The negative effects of forestry activities may persist for a long time, even after the direct impacts of these activities have diminished. In order to effectively conserve breeding areas, it may be necessary to protect suitable habitat from human activity near nests. In addition, halting illegal poisoning is a strict necessity to guarantee the conservation of colonies. Social conflict between conservationists and forest managers who employ local people in nonproductive forestry tasks could easily be resolved by conducting silviculture-related practices in areas that are unimportant for conservation and directing employment toward activities related to nature conservation.