Nightjars, rabbits, and foxes interact on unpaved roads: spatial use of a secondary prey in a shared-predator system [Dataset]

Between 2011 and 2012, we conducted transect counts of European rabbits (Oryctolagus cuniculus), red-necked nightjars (Caprimulgus ruficollis) and red foxes (Vulpes vulpes) along unpaved roads crossing the protected core of the Doñana National Park and a human-managed area located 10 km apart (37°1–7'N, 6°32–33'W). Rabbit abundance was estimated in April, June and September from transect counts conducted by driving a vehicle at a constant speed of 10-15 km/h along six different road stretches of 15 km each. Between April and September, we conducted weekly counts of road-sitting nightjars by driving a vehicle along a 35-km road circuit at a constant speed of 30 km/h, beginning 1-2 h after dusk. Fox abundance was estimated as the total number of fox sightings during the nightjar counts. In addition, in June and July 2011 and 2012 we examined the patterns of microhabitat selection by nightjars encountered during the nocturnal transects. We recorded their proximity to roadside vegetation (1 cm), measured as the perpendicular distance from the roadside, and vegetation height (1 cm).