Bird roadkill occurences in Aragon, Spain

Abstract

The increase in road networks and vehicular traffic has posed a major threat to vertebrates over the last century. Although it is difficult to determine the annual number of avian–vehicle collisions, 2 to 9 million roadkills have been estimated for Europe, with numbers varying from country to country. Few studies have been conducted at a national or regional level in Spain. In this study we used data from La Alfranca Wildlife Rehabilitation Centre database to determine location, season and incidence of avian–vehicle collisions in the autonomous county of Aragon (Spain). A total of 643 wild birds representing 71 species were killed on roads between 2012 and 2014. Nine of these species have a high incidence of avian–vehicle collisions, four a moderate incidence, and 57 a low incidence. The species with the highest incidence was the griffon vulture (120 individuals). Spatial distribution of avian–vehicle collisions was heterogeneous, and the incidence was highest in July, August and September. We identified 41 reas of high roadkill occurrence, using a number of roadkills per km index (RI): 28 in the province of Zaragoza, 9 in Huesca and 4 in Teruel. Management strategies are proposed to reduce this threat on wild birds.