Abstract Cattle grazing usually has negative effects on wildlife. We studied the effects of cattle on the patterns of habitat use and diel activity of three neotropical herbivores, capybara (Hydrochoerus hydrochaeris), gray brocket (Mazama gouazoubira) and marsh deer (Blastocerus dichotomus) across the savannas of northeastern Argentina. We conducted a camera-trap survey with 234 stations in three habitat types (grasslands, forests, pine plantations) with and without cattle. We used occupancy models to evaluate the effect of cattle (presence or recording rate), season (winter vs spring-summer, and its interaction with cattle), distance to water bodies, and density of vegetation, on the probability of detection (p) of the native herbivores. We also evaluated the effect of cattle, habitat type, structural complexity of the vegetation, proportion of marshlands and forests in the landscape, season, and relative accessibility by humans, on the probability of occupancy (ψ) of these species. Using kernel density functions, we estimated the overlap in diel activity pattern of native herbivores with that of cattle, comparing this overlap between stations with and without cattle. Several variables, but not cattle, affected ψ. For marsh deer p was lower when cattle were present. For brocket, p was much lower in winter when cattle were present. For the marsh deer and the capybara, ψ increased (but in brocket decreased) with increasing cost of human access, a proxy of hunting. For capybara and brocket, ψ increased with increasing structural complexity of vegetation. Cattle were more diurnal in grasslands than in forests and plantations. Native herbivores became more nocturnal, with lesser overlap with the diel pattern of cattle, in grasslands, when cattle were present. Cattle seem to exert interference competition on the native herbivores which used less frequently areas where cattle were present and avoided being simultaneously active with grazing cattle. Livestock production should strive to mitigate the negative competitive effects of cattle on wildlife by maintaining cattle free protected areas. It should also reduce some indirect effects of this activity on the native herbivores (e.g., hunting of wildlife and frequent burning of grasslands).

中文翻译：

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牛对南美牧场大型本地食草动物栖息地利用和日粮活动的影响

摘要 放牧牛通常会对野生动物产生负面影响。我们研究了牛对阿根廷东北部稀树草原上的三种新热带食草动物，水豚（Hydrochoerus hydrochaeris）、灰牛（Mazama gouazoubira）和沼泽鹿（Blastocerus dichotomus）的栖息地利用模式和日粮活动的影响。我们对有和没有牛的三种栖息地类型（草地、森林、松树种植园）的 234 个站点进行了相机陷阱调查。我们使用占用模型来评估牛（存在或记录率）、季节（冬季与春夏季及其与牛的相互作用）、与水体的距离和植被密度对检测概率的影响 (p)的本地食草动物。我们还评估了牛的影响、栖息地类型、植被的结构复杂性、沼泽地和森林在景观、季节和人类相对可达性中的比例，以及这些物种的占有概率 (ψ)。使用核密度函数，我们估计了本地食草动物与牛的日活动模式的重叠，比较了有牛和没有牛的站点之间的重叠。几个变量，但不是牛，影响 ψ。对于沼泽鹿，当有牛时，p 较低。对于brocket，当有牛时，冬天的p要低得多。对于沼泽鹿和水豚，ψ随着人类进入成本的增加而增加（但在brocket中减少），这是狩猎的代表。对于水豚和brocket，ψ随着植被结构复杂性的增加而增加。与森林和种植园相比，草原上的牛更昼夜活动。本地食草动物变得更加夜行，与牛的饮食模式重叠较少，在草原上，当牛存在时。牛似乎对本地食草动物施加干扰竞争，这些食草动物使用较少出现牛的区域并避免与放牧牛同时活跃。畜牧生产应通过维持无牛保护区来努力减轻牛对野生动物的负面竞争影响。它还应该减少这种活动对本地食草动物的一些间接影响（例如，狩猎野生动物和频繁焚烧草原）。畜牧生产应通过维持无牛保护区来努力减轻牛对野生动物的负面竞争影响。它还应该减少这种活动对本地食草动物的一些间接影响（例如，狩猎野生动物和频繁焚烧草原）。畜牧生产应通过维持无牛保护区来努力减轻牛对野生动物的负面竞争影响。它还应该减少这种活动对本地食草动物的一些间接影响（例如，狩猎野生动物和频繁焚烧草原）。