Prairie dogs, cattle subsidies, and alternative prey: Seasonal and spatial variation in coyote diet in a temperate grassland

As the dominant predator on North America’s grasslands, coyotes (Canis latrans) have a large influence on biodiversity, both on working ranches and in protected parks. Ground squirrel (sciurid) species and livestock carrion are often abundant on grasslands worldwide and have the potential to influence a predator’s consumption of alternative prey. We collected 1321 scats in four seasons over two years in and adjacent to Grasslands National Park, Saskatchewan, to test the hypothesis that seasonal and spatial variation in consumption of sciurid prey and cattle (Bos taurus) carrion influenced coyote consumption of alternative prey. Sciurid (black-tailed prairie dog Cynomys ludovicianus and Richardson’s ground squirrel Urocitellus richardsonii) remains were common from spring to fall and had a strong inverse relationship with deer (mule deer Odocoileus hemionus and white-tailed deer O. virginianus), which were most common in winter scats. Cattle remains were most common during spring, fall a...

作为北美草原的优势捕食者，郊狼（Canis latrans）对经营性农牧场与保护型公园内的生物多样性均具有显著调控作用。全球草原生态系统中，松鼠科（sciurid）物种与家畜腐尸通常分布广泛且储量丰富，二者均可能影响捕食者对其他替代猎物的取食策略。本研究在加拿大萨斯喀彻温省的草原国家公园及其周边区域，于两年内的四个季节中累计收集了1321份粪便样本（scats），旨在检验如下假说：郊狼对松鼠科猎物与家牛（Bos taurus）腐尸的取食存在季节与空间变异，且该变异会影响其对其他替代猎物的取食模式。松鼠科动物（包括黑尾土拨鼠Cynomys ludovicianus与理查森地松鼠Urocitellus richardsonii）的残骸在春至秋季较为常见，其出现频率与鹿类（骡鹿Odocoileus hemionus与白尾鹿O. virginianus）呈现显著负相关；鹿类残骸在冬季粪便样本中的检出率最高。家牛残骸的检出率在春季、秋季最为常见……