American Beaver: GPS and VHF tag data from resident and translocated beavers on the Price and San Rafael Rivers, Utah

Wildlife translocations can dramatically alter animal movement behavior. Thus, identifying common movement patterns post-translocation can aid in setting expectations and anticipating animal behavior in subsequent efforts. American and Eurasian beavers (Castor canadensis; C. fiber) are frequently translocated for reintroduction efforts, to mitigate human-wildlife conflict, and for use as an ecosystem restoration tool. However, little is known about movement behavior of translocated beavers post-release, especially in desert rivers where resources are patchy and dynamic. We identified space-use patterns to develop an expectation framework of beaver movement behavior for future beaver-assisted restoration efforts. We captured, tagged, translocated, and monitored 41 nuisance American beavers in desert river restoration sites on the Price and San Rafael Rivers, Utah, USA, and compared their space use to 16 resident beavers. We tracked beavers 2-7 times per week from May through October in 2019 and 2020 via GPS locations and radio-telemetry, and from May 2019 through March 2021 via passive integrated antennae installed in the rivers. Resident adult beavers were detected at a mean maximum distance of 0.86 ± 0.21 river kilometers (km; ±1 SE), while resident subadult (11.00 ± 4.24 km), translocated adult (19.69 ± 3.76 km), and translocated subadult (21.09 ± 5.54 km) beavers were detected at substantially greater maximum distances. Based on coarse-scale movement models, translocated and resident subadult beavers moved substantially farther from release sites and faster than resident adult beavers up to six months post-release. In contrast, based on fine-scale, short-term movement models over 5-minute intervals, we observed similar median distance traveled between resident adult and translocated beavers. Our findings suggest day-to-day activities such as foraging and resting were largely unaltered by translocation, but translocated beavers exhibited coarse-scale movement behavior most similar to dispersal by resident subadults. Coarse-scale movement rates decreased with time since release, suggesting that translocated beavers adjusted to the novel environment over time and eventually settled into a home range similar to resident adult beavers. This is the first study comparing resident and translocated beaver movement behavior in the same system. Understanding translocated beaver movement behavior in response to a novel desert system can help future beaver-assisted restoration efforts to identify appropriate release sites and strategies.