To learn more about the space use of river otters in West Virginia, we attached temporary GPS transmitters to 27 otters. Otters are difficult to track, but we used a new style of GPS attachment, which allowed us to collected finer-scale location data on otters than has ever been collected (Figure 1).
Of particular interest was if otters were localizing on areas that received trout stockings. Only 24 transmitters were able to be downloaded from due to transmitters becoming detached often in inactive beaver lodges, grooming areas, or open water from otters at random. Home ranges, movement rates, and resource selection were analyzed. Home ranges were larger during the stocking period (99.47 km2, 85% CI: 72.73-126.20) compared to the non-stocking period (19.41 km2, 85% CI: 0-40.81). This difference indicates that otters are not localizing on stocked areas and could point to the relevance of other covariates or factors not included in this analysis. Home ranges were larger during the breeding season (82.91 km2, 85% CI: 59.96-105.85) compared to the nonbreeding season (8.91 km2, 85% CI: 59.96-105.85). Movement rates were affected by breeding, but not by stocking. Movement rates were higher during the breeding season (398.53 m/hour; 85% CI: 334.73 - 462.34) compared to the non-breeding season (206.05 m/hour; 85% CI: 136.81 - 275.29). River otters selected locations near water, stocking, and roads, and selected for wetlands over other habitat types. This spatial data provides much needed information regarding a restored otter population and utilizes technology that has not been applied to river otters previously.
Figure 1. Animation of river otter movement collected by a GPS transmitter in March - April, 2024