Ecological and social consequences of bison reintroduction in Colorado

Abstract

Bison were instrumental in shaping North America's Great Plains. Interest in restoring this iconic species and their ecological role in grassland ecosystems is rapidly gaining momentum. To evaluate the potential for bison to enhance habitat quality for wildlife and catalyze public engagement in grassland conservation, we assessed both the ecological and social effects of a recent bison reintroduction (2015) to northern Colorado. Specifically, we explored the effect of bison reintroduction on: (a) bird density and habitat use, (b) mammal habitat use, (c) vegetation composition and structure, and (d) visitor connectedness, known as place attachment, to a shortgrass prairie. We predicted that bison reintroduction would reduce cover and height of some grasses and shrubs, which would increase density and habitat use for obligate shortgrass prairie birds, and increase habitat use for coyote and lagomorphs. In addition, we predicted that visitors would express stronger place attachment to this grassland once bison were reintroduced. To measure ecological and social responses, we surveyed birds, mammals, and plants; and conducted structured visitor surveys before and after bison reintroduction. We found few short‐term effects of bison on grassland bird density and habitat use, mammal habitat use, and vegetation composition and structure. However, we measured a significant increase in visitor place attachment to the grassland site 1 year after bison reintroduction. Our results suggest that a new bison reintroduction may have immediate positive benefits for connecting people to conservation, and that the ecological and social effects may unfold over different time scales. We recommend that future bison reintroduction efforts monitor ecological and social outcomes to advance reintroduction biology.