Artificial night lighting determines nest-site selection and habitat use by Burrowing owl

JOSÉ HERNÁN SARASOLA; RODRIGUEZ, AIRAM; PAULA MAITEN OROZCO VALOR

Skukuza- Kruger National Park

Conferencia; Raptor research foundation conference; 2018

Light pollution caused by artificial lights in urban areas can potentially affect wildlife. Here we examine the effects of artificial night lights on habitat use and nest-site selection of a nocturnal avian predator, the Burrowing owl (Athene cunicularia), in an urban environment. Fifteen owls were tagged with GPS data loggers that recorded individual?s locations every one minute for 4-6 days from bird tagging to recapture. Habitat characteristics, including nest-site habitat structure and distances from nests to the nearest artificial lights, houses and roads were recorded for 27 active owl nests and for 39 randomly-selected locations within the study area. In addition, insect prey availability was assessed behind ten artificial lights and in ten control sites without lights by setting pit-fall traps. Distance to the nearest artificial light was the single variable explaining nest-site selection by owls. Owls? nests were located significantly closer to artificial light than the expected by chance. In addition, GPS individual?s locations during the night were clustered in areas around artificial lights, while during the day owls were closer to their nests. Our results show that artificial night lighting may be determining both habitat use and nest-site selection by the Burrowing owl in urban environments. Burrowing owls apparently thrive in many cities across the Neotropics although the reason of such success in these human-made environments are still unknown. Artificial lights could be either playing a key role on the colonization process of urban habitats by burrowing owls or providing foraging advantages to those owls that have been able to get into and succeed in these novel environments.