Camaratta Danielle, Chaves Óscar M, Bicca-Marques Júlio César
Departamento de Biodiversidade e Ecologia, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Organização Fauna Brasilis, Bairro Lami, Porto Alegre, Rio Grande do Sul, Brazil.
Am J Primatol. 2017 Mar;79(3):1-8. doi: 10.1002/ajp.22626.
Understanding the ecological factors that influence the presence, abundance, and distribution of species within their habitats is critical for ensuring their long-term conservation. In the case of primary consumers, such as most primates, the availability and richness of plant foods are considered key drivers of population density at these variables influence the spatial distribution of social units within a finer, habitat patch level scale. We tested the hypothesis that the spatiotemporal availability and richness of plant foods, drive the spatial distribution of brown howler monkeys (Alouatta guariba clamitans) at a fine spatial scale. We established five line transects (2.6-4.3 km long) to census the population of brown howlers in Morro São Pedro, a 1,200 ha Atlantic forest remnant in southern Brazil, every 2 weeks from January to June 2015. We used data from tree inventories performed in sighting and control plots, and phenological surveys of 17 top food tree species to estimate bi-weekly food availability. We recorded a total of 95 sightings. The number of sightings per sampling period ranged from 2 to 12. The availability of fruit (ripe and unripe) was higher in sighting than in control plots, whereas leaf availability and the richness of food tree species was similar. We conclude that the spatial distribution of fruiting trees and the availability of fruit drive the pattern of habitat use, and spacing of brown howler groups in Morro São Pedro.
了解影响物种在其栖息地中的存在、数量和分布的生态因素对于确保它们的长期保护至关重要。就大多数灵长类等初级消费者而言，植物性食物的可获得性和丰富程度被视为种群密度的关键驱动因素，因为这些变量会在更精细的栖息地斑块尺度上影响社会单位的空间分布。我们检验了这样一个假设：植物性食物的时空可获得性和丰富程度在精细空间尺度上驱动了褐吼猴（Alouatta guariba clamitans）的空间分布。我们在巴西南部一片面积为1200公顷的大西洋森林残余地莫罗圣佩德罗设立了5条样线（长2.6 - 4.3千米），从2015年1月至6月每两周对褐吼猴种群进行一次普查。我们利用在观测和对照样地进行的树木清查数据以及对17种主要食物树种的物候调查来估算每两周的食物可获得性。我们总共记录了95次观测。每个采样期的观测次数在2至12次之间。观测样地中果实（成熟和未成熟）的可获得性高于对照样地，而树叶的可获得性和食物树种的丰富程度则相似。我们得出结论，结果实树木的空间分布和果实的可获得性驱动了莫罗圣佩德罗地区褐吼猴的栖息地利用模式和群体间距。
