Roads, forest cover, and topography as factors affecting the occurrence of large carnivores: The case of the Andean bear (Tremarctos ornatus)

• Main Authors: N. Morrell, R.D. Appleton, P. Arcese
• Format: Article
• Language: English
• Published: Elsevier 2021-04-01
• Series: Global Ecology and Conservation
• Subjects: Habitat use; Equatorial dry forest; Multi-year camera trap; Patial capture-recapture; Human influence; Tremarctos ornatus
• Online Access: http://www.sciencedirect.com/science/article/pii/S2351989421000238

Global declines in large-bodied terrestrial vertebrates are widely linked to human disturbance and habitat loss. Identifying remaining opportunities to conserve areas wherein such species may persist or might be reintroduced has thus become a key challenge in biodiversity conservation globally. We used multi-year camera trap data and spatial capture-recapture models to test how individually-identified Andean bears (Tremarctos ornatus) responded to roads and a suite of forest cover and topographic variables that may be indicative of food resources in critically-threatened, equatorial dry forest habitats of northern Peru. Bear density averaged 4 individuals per 100 km2 in our 668 km2 study area, but proximity to roads significantly reduced density, possibly because they are avoided and/or facilitate demographic sinks or human hunting. In contrast, the effects of forest cover and topographic variables on bear density varied seasonally, reflecting documented variation in mating behavior that may result from seasonal food resources. Despite large uncertainties in model predictions on the occurrence of bear habitat outside our study area, extrapolating our results suggests that a substantial area of high-quality habitat for Andean bears exists outside the recognized IUCN range, including equatorial dry forest habitats known to harbor many threatened species. Because Andean bears are vulnerable to extinction and are an established flagship species in much of South America, the expanded range and potential habitats that we identify here require urgent validation for possible inclusion in landscape-level plans to conserve equatorial dry forests of the Andes.