Forest structure has stronger effects than cattle occurrence on the occupancy of a carnivore guild

Abstract

Anthropogenic activities can profoundly affect ecological communities. This is true of the most ubiquitous type of anthropogenic land-use, livestock grazing. While livestock grazing is known to impact vegetation structure, soil, and hydrological features, the effects of livestock occurrence on animal communities are often more complex. Herein, we estimated the relative effects of cattle occurrence and vegetation structure on the occupancy of a carnivore guild in northern California and southern Oregon, USA. We used remote cameras to non-invasively collect detection and non-detection data of cattle and nine carnivore species. We incorporated detection data into a Bayesian hierarchical occupancy model to estimate the effects of livestock occurrence and vegetation structure on carnivore occupancy. We found varied effects of cattle occurrence on carnivore occupancy, with most species showing no clear response to cattle occurrence. Vegetation structure, including structural diversity and vegetation productivity, had stronger effects on carnivore occupancy than cattle occurrence. This work provides an exploration of the effects of cattle occurrence and forest structure on carnivore space-use in a grazed forest system, and suggests vegetation structure may have stronger effects than cattle occurrence on carnivore occupancy in grazed forest systems. Future work to clarify the direct and indirect effects of livestock occurrence can inform conservation and management strategies in forested ecosystems.

Keywords

• Bayesian modelling
• Camera trap
• Community ecology
• Human-wildlife interactions
• Livestock-carnivore interactions
• Occupancy modelling