Ryan Herbert

I am interested in researching the behavioral ecology of wild, feral horses (Equus ferus caballus) in the American West for the sake of conservation.  These horse populations are now above 100,000 individuals, nearly half of which are in long-term holding facilities run by the Bureau of Land Management (BLM).  A lack of predators in the Western ranges of most horses prevents top-down control within nature, and effective population management has not been enacted.  Therefore, bottom-up controls, such as limited forage, are expected to be the main determinants of horse population sizes.  Yet, potential economic and environmental impacts have led cattle ranchers and ecologists alike to call for strong interventions before uncontrolled horse populations continue their rapid growth.  The U.S. government is considering culling as many as 75,000 horses to reach the BLM’s appropriate management level of ~25,000. 

Because many assumptions of horse ecology are directing current policy, my work will attempt to quantify how correct these assumptions are.  For example, cattle and other livestock may be exerting greater grazing pressure on fragile ecosystems.  Potentially, horses may align with ranching interests, improving cattle grazing by eating undesirable plant parts.  Climate stands as another factor that may have more influence on species composition and abundance than horse grazing.  In addition to these considerations, I would like to study movement patterns of horses to better understand their geospatial relationships within Western ecosystems.  This work is intended to expand our knowledge of horse ecology so that policy makers may best decide whether horses can coexist with the natural and economic environments of the American West.