Understanding Sex-Specific Behavioral States of Bobcats in Response to Highway Proximity in South Texas

Roads are a major source of landscape fragmentation that can influence movement patterns, survival, and behavioral states of carnivore species. Understanding their behavior and response to roads is crucial for developing effective mitigation strategies such as wildlife crossing structures, exclusion fencing, and habitat connectivity planning. We examined the behavioral response of bobcats (Lynx rufus) from private ranchlands adjacent to US Highway 77 in South Texas. We used GPS collar data to track the movement of 10 bobcats (six males and four females) to quantify fine-scale movement behavior and space use. We used Hidden Markov Models (HMMs) to predict three behavioral states of each individual movement pattern: State 1 (resting), State 2 (moderately active), and State 3 (traveling). Our model indicated that the interaction of distance to the highway and sex influenced bobcat behavioral state transitions. Male and female bobcats differed in nocturnal movement behavior, with females exhibiting slightly longer mean step length (distance between two consecutive relocations) than males, while turning angles (angle between previous and current displacement) were similar between both sexes during the resting state. Both sexes spent most of their time in the moderately active state (State 2) across all distance to highway classes. This behavior is consistent with foraging, territorial patrolling, and searching for mates during night hours. Although both sexes were moderately active, females reduced movement closer to the highway, whereas males showed more extensive travel. Home ranges of some bobcats overlapped and frequently abutted US Highway 77, suggesting the highway may function as a behavioral and spatial boundary. These findings highlight how expanding highways may reduce functional connectivity for bobcats and other felids and may inform mitigation strategies to reduce wildlife-vehicle collisions, with potential applications for the conservation of sympatric felids like ocelots (Leopardus pardalis).