This study found that prescribed fires conducted under favorable conditions (2011) induced potentially positive bighorn responses including high survival and increased use of treated areas. Fires during drought conditions were more widespread with little vegetative response (2012) and coincided with increased bighorn mortality in spring 2013.
Dead bighorns with poor body condition had high home range overlap with burned areas. We suggest that large fires coupled with unfavorable weather conditions rendered bighorns unable to access adequate forage to meet nutritional requirements. Because impacts of fires on bighorn populations are highly dependent on ensuing vegetative recovery, consideration should be given to the timing, extent, and spatial coverage of prescribed fires. Therefore, we recommend conducting prescribed fires before bighorn reintroductions, or conducting prescribed fires on a relatively small scale and on a rotational basis to avoid reducing foraging options.