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Wildlife exclusion fencing can significantly reduce wildlife–vehicle collisions. However, some animals breach the fence and become trapped in the highway corridor, thereby increasing risk of a wildlife–vehicle collision. An emerging solution to this problem is the installation of earthen escape ramps (i.e., jumpouts), which allow trapped animals to escape the highway corridor. Few studies have quantified wildlife use of jumpouts, and none have investigated intraspecific differences in use. We used camera traps to document wildlife use of 4 2m-high jumpouts associated with wildlife exclusion fencing along Highway 101 near San Luis Obispo, California, USA, from 2012 to 2017. We surveyed for 7,361 nights across all 4 jumpouts, yielding 1,015 visitation events by 10 different species of large- and medium-sized mammals. Mule deer (Odocoileus hemionus) accounted for 895 (88%) detections; they jumped out 20% of the time when detected at the top of the ramp and were never detected using the jumpout to enter the highway corridor. We differentiated male and female deer using the presence of antlers and found that they jumped out at similar rates, but females were detected 6 times more often and were more likely to return to the same jumpout. Two groups of 2–3 deer accounted for ~41% of deer detections, which allowed us to investigate their behavior over time. These results indicate that individual variation could influence jumpout use, which should be considered when quantifying their use. To increase the overall jumpout rate, we recommend a jumpout height between 1.75 and 2 m.

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