An animal's welfare state is directly influenced by the mental state, which is shaped by experiences within the environment throughout the animal's life. For zoo-housed animals, visitors to the zoo are a large part of that environment and a fluctuating influence within it. This study examines the impact of zoo visitors on the space use of five species of zoo-housed primates (Eastern black-and-white colobus monkeys, Colobus guereza, n = 5, Allen's swamp monkeys, Allenopithecus nigroviridis, n = 2, DeBrazza's monkeys, Cercopithecus neglectus, n = 3, Bolivian gray titi monkeys, Callicebus donacophilus, n = 3, and crowned lemurs, Eulemur coronatus, n = 3). Specifically, we considered whether primates' distance from visitor areas changed as crowd sizes increased. Data were collected using the ZooMonitor app. Observers recorded spatial coordinates for each animal over periods ranging from 12 to 32 months. Data were analyzed using two types of regression models (linear and logistic) to examine the influence of visitors on the location of the primates. Both analyses revealed a statistically significant but small decrease in primate distance from visitor viewing glass as the number of visitors increased. Behavioral indicators of welfare were also unaffected by the presence of visitors. These results suggest that, with additional validation, distance from visitors may be one promising, simple way to evaluate the influence of visitors on primate welfare.

中文翻译：

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动物园里的灵长类动物会从人群中撤退吗？五种灵长类动物的简单研究

动物的福利状态直接受到精神状态的影响，而精神状态是由动物一生中在环境中的经历所塑造的。对于动物园饲养的动物，动物园的游客是该环境的很大一部分，并且在其中起着波动的影响。本研究调查了动物园游客对动物园内五种灵长类动物（东部黑白疣猴、Colobus guereza、n  = 5、艾伦沼泽猴、Allenopithecus nigroviridis、n  = 2、DeBrazza 猴）空间利用的影响, Cercopithecus neglectus , n  = 3, 玻利维亚灰猴, Callicebus donacophilus , n  = 3, 和加冕狐猴,Eulemur coronatus , n  = 3). 具体来说，我们考虑了灵长类动物与游客区域的距离是否随着人群规模的增加而改变。使用 ZooMonitor 应用程序收集数据。观察员在 12 到 32 个月的时间段内记录了每只动物的空间坐标。使用两种类型的回归模型（线性和逻辑）分析数据，以检查访客对灵长类动物位置的影响。两项分析均显示统计上显着但小幅下降随着游客数量的增加，灵长类动物与游客观察玻璃的距离越来越远。福利的行为指标也不受访客的影响。这些结果表明，通过额外的验证，与游客的距离可能是一种有前途的简单方法来评估游客对灵长类动物福利的影响。