Effects Of Resident Conspecific Density and Ecotype Mismatch? Settlement Timing and Resource Use of Restocked Desert Bighorn Sheep into a High-Density Population

<span>Post-release behavioral responses may influence translocation success, yet relatively little is known about the timing of settlement and resource use of restocked animals into a high-density population. We therefore evaluated settlement timing and resource use of 16 (9 F, 7 M) desert bighorn sheep (<i>Ovis canadensis mexicana</i>) restocked into a high-density population in Sonora, Mexico. We applied a nonparametric Bayesian mixed-membership method to determine&nbsp;</span><span>settlement and modeled resource use using generalized linear regression. Settlement occurred rapidly, averaging 5.2 days (95% CI: 1.9–8.5). Resource use differed before and after settlement, with unsettled individuals primarily using low-elevation, gentle sloped foothills surrounding mountains, resembling conditions in the source range. Following settlement, individuals shifted to higher elevations, steeper slopes, and areas closer to escape terrain. Our findings, in the context of previous work, suggest that resident conspecific density is a key determinant of the duration of the exploratory period, forming a continuum that may range from days in high-density settings to months or longer following reintroduction. We also found that slight ecotype mismatches can influence resource use; however, behavioral plasticity, likely mediated by social interactions and integration, resulted in a post-settlement shift toward resources that likely reduced predation risk. Use of foothills consistent with the source range may have further facilitated conspecific detection, either directly or indirectly. Together, these results provide a predictive framework for how resident conspecific density influences settlement timing and associated risks, with implications for restocking and reintroduction strategies in bighorn sheep restoration.</span>