Northern Goshawk breeding sites indicate the presence of mature forest in Mediterranean pinewoods

Abstract

Forestry practices based on fire prevention and biomass acquisition for energetic purposes may have negative effects on biodiversity. To ensure that forest management is compatible with biodiversity conservation, the identification and use of surrogate species such as forest-dwelling raptors is known to be effective. In this study, we analyse nest site selection of the Northern Goshawk (Accipiter gentilis), an acknowledged surrogate species in boreal and cool-continental forests, in a Mediterranean mid-altitude mountain ranges in Catalonia (NE Spain). Our aims were both (i) to determine Goshawk nest site selection in terms of forest structure and human presence and (ii) to highlight the need for sustainable forestry practices based on the conservation of this forest raptor. Goshawks selected large-pines in forest stands with high densities of mature pines and young broad-leaved trees, as well as high shrub cover, on relatively steep slopes and in territories with low cover of urbanized land and few roads. These characteristics indicate their preference for mature, well-preserved forests with little human disturbance. In our study area, Goshawks nest in pine forests which are endangered at a regional scale: black pine (Pinus nigra salzmannii) and Scots pine (P. sylvestris), but also Aleppo pine (P. halepensis) as a common used species. Nest site properties selected by Goshawks suggest that this species acts as an indicator species of forest maturity and low human-disturbed area in Mediterranean pinewoods and, consequently, to conserve Goshawk sites, forest management should not alter the structural properties necessary for nest site occupancy. Future research should assess more fully the role of this avian predator as a biodiversity indicator in Mediterranean forests.