Small selective ungulate species differ in habitat use within transformed landscapes of the Overberg, South Africa

The Renosterveld vegetation in the Overberg, Western Cape (South Africa) is listed as critically endangered with more than 80% of Renosterveld transformed for agricultural purposes. Remaining natural vegetation consists mostly of small patches that are situated far apart. The landscape between these patches is filled with agricultural land used for grain crops, vineyards, indigenous flower crops and livestock farming. The remaining patches of natural vegetation is being conserved providing the wildlife in the area with corridors and small protected areas. The objective of this study was to determine how the habitat use of five small specialist browser species are affected by anthropogenic land use. These species were bushbuck (Tragelaphus sylvaticus), Cape grysbok (Rhaphicerus melanotis), common duiker (Sylvicapra grimmia), grey rhebok (Pelea capreolus) and steenbok (Rhaphicerus campestris). To determine which site-specific characteristics were the strongest drivers of habitat use during each season we ran occupancy models using camera trap data and covariate data collected around camera trap sites to run single species, single season occupancy models. The results suggest that some species appear dependent on the anthropogenic landscape, while still relying on the natural vegetation for cover and resources. In contrast, other species however appear to be more dependent on the natural landscape and occasionally use the anthropogenic landscape to their advantage.南非西开普省奥弗贝格地区的雷诺斯韦尔德（Renosterveld）植被被列为极危物种，已有超过80%的该类植被被改造为农业用地。剩余的天然植被多为相互隔离的小型斑块。这些斑块之间的区域多为用于谷物种植、葡萄园营建、本土花卉栽培以及畜牧养殖的农业用地。目前现存的天然植被斑块正得到保护，为该区域的野生动物提供了迁徙廊道与小型保护地。本研究旨在探究五种小型特化啃食型动物物种的生境利用方式受人为土地利用的影响程度。本次研究涉及的五个物种分别为：薮羚（Tragelaphus sylvaticus）、海角小羚（Rhaphicerus melanotis）、普通麂羚（Sylvicapra grimmia）、灰小苇羚（Pelea capreolus）以及小羚（Rhaphicerus campestris）。为明确各季节内哪些生境特异性特征是驱动生境利用的最主要因素，本研究利用相机陷阱（camera trap）数据及相机陷阱站点周边收集的协变量数据，构建了单物种单季占用模型（occupancy model）。研究结果显示，部分物种似乎依赖人为改造的景观，但仍需依托天然植被获取遮蔽与生存资源；与之相反，其余物种则更依赖天然景观，仅偶尔会利用人为景观以获取生存益处。