Effects of Seasonal Folivory and Frugivory on Ranging Patterns in Rhinopithecus roxellana

Abstract

The distribution of food resources in time and space may affect the diet, ranging pattern, and social organization of primates. We studied variation in ranging patterns in a group of Sichuan snub-nosed monkeys (Rhinopithecus roxellana) over winter and summer in response to variation in their diet in the Qingmuchuan Nature Reserve, China. There was a clear diet shift from highly folivorous in winter to highly frugivorous in summer. The home range was 8.09 km 2 in summer and 7.43 km 2 in winter, calculated via the 95% kernel method. Corresponding to the diet shift, the focal group traveled significantly longer distances in summer (mean 1020± 69 m/d) than in winter (mean 676±53 m/d); the daily range was also significantly greater in summer (mean 0.27±0.02 km 2 /d) than in winter (mean 0.21±0.01 km 2 /d).There was no significant variation in home range size between winter and summer, and the monkeys did not use geographically distinct ranges in summer and winter. However, overlap in the actual activity area and core range between winter and summer was only 0.13 km 2 , representing 4.4% of the summer core area and 5.3% of the winter core area. Differences were apparent between summer and winter ranging patterns: In summer, the group traveled repeatedly and uninterruptedly across its home range and made 3 circles of movement along a fixed route in 31 d; in winter, the activity area was composed of 3 disconnected patches, and the focal group stayed in each patch for an average of 8 successive days without traveling among patches. Winter range use was concentrated on mixed evergreen and deciduous forest patches where leaves and fruits were available, whereas the summer range Int J Primatol (2010) 31:609-626 pattern correlates significantly positively with the distribution of giant dogwood (Cornus controversa) fruits. Thus it appears that the diet shift of Sichuan snub-nosed monkeys between winter and summer caused the monkeys to use their home range in different ways, supporting the hypothesis that food resources determine primate ranging patterns.

Ranging pattern and population composition of Rhinopithecus bieti at Xiaochangdu, Tibet: Implications for conservation

“…For example, Kirkpatrick et al [43] and Liu et al [44] found that R. bieti had a larger home range during summer and traveled further each day when preferred foods were available. Our results are also consistent with studies of R. roxellana which report that DTL increases significantly in autumn and summer when food available is high [45][46][47]. This study supports the hypothesis that both the amount of travel required to find fruits and the time and energy available for traveling increase as the fruits in the diet increase [48].…”

Snub‐nosed monkeys: Multilevel societies across varied environments

“…Here, travel distances are bimodal in winter but not in summer. 32 This is to be expected if range use is driven by the nature of food resources, which will differ as diets change over the seasons.…”

Altitudinal Movements of Guizhou Snub-Nosed Monkeys (Rhinopithecus brelichi) in Fanjingshan National Nature Reserve, China: Implications for Conservation Management of a Flagship Species

“…that live in temperate, mountainous regions in China [Kirkpatrick and Long, 1994;Kirkpatrick et al, 1998;Tan et al, 2007;Li et al, 2008;Zhong et al, 2008;Li et al, 2010]. Snub-nosed monkeys are members of the subfamily Colobinae or 'leaf-eating monkeys'.…”

“…nov. at 1,400-3,400 and 1,720-3,190 m, respectively, in temperate mixed deciduous broadleaf and conifer forest and R. bieti at 2,600-4,600 m in temperate mixed forest dominated by fir [Kirkpatrick, 1998;Yang et al, 2002;Tan et al, 2007;Li et al, 2008;Grueter et al, 2009;Geissmann et al, 2011;Kirkpatrick and Grueter, 2010;Li et al, 2010]. Regarding al-titudinal ranging, it has been suggested that R. bieti and R. roxellana adjust their movements in relation to food availability, human activities and climate [Hu et al, 1980;Zhao et al, 1988;Kirkpatrick and Long, 1994;Kirkpatrick et al, 1998;Su et al, 1998;Yang, 2003;Liu et al, 2004;Tan et al, 2007;Li et al, 2008;Zhong et al, 2008].…”