Bird mortality on high-speed railways: Lessons from two large contrasting species

<p>Collisions are the chief effect of transport infrastructures on vertebrate populations but their relevance in high-speed railways (HSR) is largely unknown. We analyzed Great Bustard (Otis tarda) and Eurasian Eagle-owl (Bubo bubo) mortality along two 5-km stretches of a Spanish HSR. Five fresh bustard and 10 owl carcasses were collected during 40 weeks of monitoring over two years, plus older remains of 14 bustards and 17 owls more. Relevant mortalities of both bird species thus occur, and differences in local use of the infrastructure explain their spatial patterns. Bustards die at points where they fly across optimizing their local movements according to MaxEnt models, while owls die while hunting the abundant rabbits present in railway verges as pointed by camera trapping. Impact prediction, evaluation and mitigation must therefore accommodate to species’ characteristics.</p>