Reactions of a colonial seabird species to controlled gunshot disturbance experiments

Gunshots are a worldwide source of anthropogenic disturbance, and knowledge about the potential effect on wildlife is central for conservation sustainable management affected species. This study contributes novel insight response behaviour gunshot disturbance one most culturally important seabird species Arctic, thick-billed murre (Brünnich's guillemot, Uria lomvia). We studied effects at breeding colonies to explore distance where started, difference in behavioural between presumed disturbed (e.g. by traffic hunting) largely undisturbed colonies, among plots with varying densities. carried out two different types controlled experiments – measuring which murres first reacted gunshots (flight initiation distance, ‘FID') proportion remaining colony during after repeated (20 within 78 min). FID varied from 0.5 5 km. The plot ranged 0.44 0.8. Mainly not attending offspring took off when gunshots, but occasionally also birds incubating their egg or brooding chick off. found that density seabirds (murres black-legged kittiwakes Rissa tridactyla) area scale was best explaining factor FID, some extent both colonies. Murres denser earlier (had larger FIDs) somewhat more strongly (higher proportions fleeing) than less densely populated clearly showed current legislation Greenland regulating near insufficient. provide recommendations improved popular game under pressure.