Though useful for analyzing landscape-scale patterns, habitat models must be assessed in the field to verify their real-world applicability. In partnership with the Karuk Wildlife Team, we evaluated several methodologies to assess the validity of a Pacific fisher habitat connectivity model created by the Conservation Biology Institute. The model mapped habitat suitability and connectivity linkages that may serve as least-cost paths and "corridors" for fishers to travel between important habitat cores. Using camera traps across the spring mating season when fishers travel widely, we tested several methods for detecting fisher movements: a baited camera grid design, unbaited cameras placed at key linkage points, and habitat surveys to ground-truth the model outputs.

Baited camera traps confirmed fisher occupancy in modeled core habitat adjacent to potential linkage sites, the first reported fisher detections in some sites. Fishers were seldom detected in linkage habitat and unbaited camera locations. Habitat quality across cores and potential crossing structures varied depending on recent fire conditions, but failed to predict fisher occupancy. While camera traps adequately detected fisher across associated habitats, we could not confirm whether the same individuals traveled across the linkage. Genetic analyses or radio telemetry, when feasible, would deepen our understanding of fisher dispersal through fragmented landscapes and allow thorough model validation.