Seasonal and individual variation in the use of rail-associated food attractants by grizzly bears (Ursus arctos) in a national park

摘要: Similar to vehicles on roadways, trains frequently kill wildlife via collisions along railways. Despite the prevalence of this mortality worldwide, little is known about relative importance attractants associated with railways, including spilled agricultural products, enhanced vegetation, invertebrates, and carcasses rail-killed ungulates. We assessed several railway a provincially-threatened population grizzly bears (Ursus arctos) in Banff Yoho National Parks, Canada, for which rail-caused has increased recent decades without cause. examined relationship between use diet by fitting 21 GPS collars 2011–2013 measuring stable isotope values (δ15N, δ34S) derived from their hair. also rail-associated foods analyzing 230 bear scats collected May through October 2012–2014, some could be attributed GPS-collared bears. Among collared bears, 17 used rail rarely ( 20% monitored days). found no significant relationships δ15N δ34S measured hair grizzlies frequency use. Instead, body mass, especially male suggesting large males consumed more animal protein during growth. All four that produced containing grain. Almost half (43%) within 150 m contained grain compared only 7% >150 railway. Scats deposited near were likely contain fall (85% scats) summer (14%) spring (17%), those diverse contents (6.8 ± 2.2 species vs. 4.9 1.6, P < 0.001). Lastly, ungulate ant remains, summer. Our results support local management knowledge region forage supplement diets grain, but individual highly variable. suggest managers continue reduce risk being killed reactively removing railway, reducing amount trains, target mitigation specific individuals locations attract recurrent rail-based foraging.