Influence of human footprint and sensory disturbances on night-time space use of an owl

Abstract

Artificial sensory disturbances (sound and light) can extend far beyond the physical footprint of human development. Nocturnal predators such as owls may be influenced by artificial sound and light, as they depend on aural and visual cues when hunting. Owl nocturnal movements may also be altered by physical changes to the landscape, as these can affect prey availability. The burrowing owl population in Canada has declined by 90% and was classified as endangered in 1995. We tracked adult male burrowing owls Athene cunicularia with GPS dataloggers, and used resource selection models to examine their night-time movement patterns in relation to human infrastructure and associated artificial light and sound. The amount of sound and light from compressor stations, oil wells, traffic, towns and buildings was calculated for each owl and random location. We found that owl night-time space use was better predicted by distance to infrastructure on the landscape than by intensity of sensory disturbance. Burrowing owls did not show a pronounced avoidance of artificial sound. Infrastructure best predicts owl space use, perhaps because associated changes to vegetation alter prey abundance and availability. While human infrastructure most influenced owl nocturnal space use, the extent to which ecosystems are impacted by artificial sound and light is becoming clearer and needs to be considered when assessing the total effect of human development on species.

The effect of industrial noise on owl occupancy in the boreal forest at multiple spatial scales

“…However, owls are unlikely to vocalize while hunting, so it is not likely we detected them in noisy areas while they were trying to hunt. A study tracking western Burrowing Owls with transmitters found that nocturnal space-use was not affected by industrial noise (Scobie et al 2016). Future research tracking these three species of owls found in the boreal forest will be necessary to understand how these species' behavior and movement is influenced by noise sources.…”

“…Increasing industrial noise levels negatively affect the hunting success of Northern Sawwhet Owls (Aegolius acadicus; Mason et al 2016), and reduce the foraging efficiency of Long-eared Owls (Asio otus) and Shorteared Owls (Asio flammeus; Senzaki et al 2016). However, a study on the nocturnal space use of Western Burrowing Owls (Athene cunicularia hypugaea) found they did not avoid areas affected by anthropogenic noise (Scobie et al 2016). A study on Spotted Owls (Strix occidentalis) found they will flush from nests more frequently with increased proximity to a noise source (Delaney et al 1999).…”

Juvenile Burrowing Owl Nighttime Space-Use In Southern New Mexico

“…Means (log-transformed ratios), standard error (SE) and t-test results for pairwise comparison of cover types available to juvenile owls are presented. Significance was determined at P value 0.05. importance of ecotones in agricultural landscapes for Burrowing Owls, possibly due to increased prey abundance and biomass in agriculture habitats (Rich 1986, Haug and Ophilant 1990, Leptich 1994, Moulton et al 2006, Marsh et al 2014a, Scobie et al 2016.…”

“…Owls nesting in highly agricultural areas used this habitat in proportion to its availability, whereas other owls appeared to seek out this habitat type. Other studies have found extensive use of agriculture by Burrowing Owls but agriculture made up a large portion of available land-cover types (Haug and Oliphant 1990, Sissons et al 2001, Gervais et al 2003, Marsh et al 2014a, Scobie et al 2016. In these situations, owls often either used this land classification in relation to availability (Gervais et al 2003) or Figure 1.…”

“…Burrowing Owls used roads more frequently than expected in mixed-use grasslands of Saskatchewan, Canada (Marsh et al 2014b). However, in another study, Burrowing Owls in Alberta and Saskatchewan avoided infrastructure (Scobie et al 2016). In areas dominated by agriculture, juveniles forage along habitat edges and in fallow fields (Gervias et al 2003), but no data are available for urban habitats or diverse landscapes that include mixtures of agriculture, urban environments, and greenspace.…”