Abstract Management of rangelands requires knowledge of forage species that are preferred or avoided by wildlife and livestock. A recent expansion of woody vegetation into previously open grasslands in African savanna ecosystems negatively impacts many mammalian grazers. Nevertheless, the ecological role of bush encroacher plant species as food may present a benefit for browsing species. We quantified diet selection by Masai giraffes (Giraffa camelopardalis tippelskirchi) through foraging observations and vegetation sampling in the Tarangire Ecosystem of Tanzania, which includes large areas of a native shrub that livestock managers have classified as an encroacher species (Dichrostachys cinerea). We compared woody plant species used by giraffes for foraging with availability at two different spatial scales during the wet and dry seasons. Giraffes selected some woody plants such as Vachellia species while significantly avoiding others, both at the local and landscape scales. Giraffes preferred foraging on D. cinerea at both spatial scales and in both the wet and dry seasons. Management that has focused on benefiting grazing livestock by removal of encroaching species (e.g., D. cinerea) may have unintended consequences for wildlife, especially for browsing species like giraffes that feed extensively on the expanding bush species.

中文翻译：

---

马赛长颈鹿 (Giraffa camelopardalis tippelskirchi) 在多个空间尺度上的草料选择

摘要 牧场管理需要了解野生动物和牲畜喜欢或避免的牧草种类。最近在非洲稀树草原生态系统中将木本植被扩展到以前开放的草原对许多哺乳动物食草动物产生了负面影响。然而，灌木入侵植物物种作为食物的生态作用可能对浏览物种带来好处。我们通过在坦桑尼亚塔兰吉雷生态系统中的觅食观察和植被采样，量化了马赛长颈鹿 (Giraffa camelopardalis tippelskirchi) 的饮食选择，其中包括大面积的原生灌木，牲畜管理者将其归类为入侵物种 (Dichrostachys cinerea)。我们比较了长颈鹿用于觅食的木本植物物种在雨季和旱季在两个不同空间尺度上的可用性。长颈鹿选择了一些木本植物，例如 Vachella 物种，同时在当地和景观尺度上都显着避开了其他植物。长颈鹿更喜欢在空间尺度和干湿季节在 D. cinerea 上觅食。专注于通过清除入侵物种（例如灰霉病）来使放牧牲畜受益的管理可能会对野生动物产生意想不到的后果，特别是对于像长颈鹿这样广泛以不断扩大的灌木物种为食的觅食物种而言。在两个空间尺度上以及在雨季和旱季的灰霉病。专注于通过清除入侵物种（例如灰霉病）来使放牧牲畜受益的管理可能会对野生动物产生意想不到的后果，特别是对于像长颈鹿这样广泛以不断扩大的灌木物种为食的觅食物种而言。在两个空间尺度上以及在雨季和旱季的灰霉病。专注于通过清除入侵物种（例如灰霉病）来使放牧牲畜受益的管理可能会对野生动物产生意想不到的后果，特别是对于像长颈鹿这样广泛以不断扩大的灌木物种为食的觅食物种而言。