Fencing restricts and alters movement in the endangered Masai giraffe

Movement is a critical component of an animal’s ecology, shaping gene flow, population dynamics, and ecosystem processes. Fencing is a particularly pervasive feature of human-altered landscapes and is increasingly recognized as a serious impediment to movement. Despite this, our understanding of how fencing alters movement remains understudied. Here, we investigate how the movement of Masai giraffe ( Giraffa tippelskirchi ), an endangered ungulate, is impacted by fencing in Kenya’s Athi-Kapiti Plains, an area that has faced dramatic increases in human population growth and land-use change. Using barrier behavior, recursion, and integrated step selection analyses, we evaluate how fences influence Masai giraffe movement, exploring patterns among and within individuals across different times of day. We test seven hypotheses related to the impacts of fencing on behavioral responses, movement characteristics, and location selection. We show that Masai giraffe avoid encounters with fences, and that when they do encounter a fence, they are less likely to cross it or exhibit normal movements. Furthermore, fencing affects both location selection and movement patterns, with extensive individual variation in how step length and turn angle vary with fencing but a clear pattern of fence avoidance. Given considerable inter- and intra-individual variation in the mechanics of how fencing affects movement, fencing drastically altered all aspects of Masai giraffe behavior and was consistently restrictive to space use. Fencing, although sometimes overlooked given its abundance in landscapes, is a serious threat, and effective conservation actions are needed to facilitate the movements and long-term persistence of Giraffa spp. and other wide-ranging species.