Winter Food Abundance for Japanese Monkeys in Differently Aged Japanese Cedar Plantations in Snowy Regions

There is a great deal of spatial and temporal variation in the availability and nutritional quality of foods eaten by animals, particularly in temperate regions where winter brings lengthy periods of leaf and fruit scarcity. We analyzed the availability, dietary composition, and macronutrients of the foods eaten by the northern-most golden snub-nosed monkey (Rhinopithecus roxellana) population in the Qinling Mountains, China to understand food choice in a highly seasonal environment dominated by deciduous trees. During the warm months between April and November, leaves are consumed in proportion to their availability, while during the leaf-scarce months between December and March, bark and leaf/flower buds comprise most of their diet. When leaves dominated their diet, golden snub-nosed monkeys preferentially selected leaves with higher ratios of crude protein to acid detergent fiber. While when leaves were less available, bark and leaf/flower buds that were high in nonstructural carbohydrates and energy, and low in acid detergent fiber were selected. Southern populations of golden snub-nosed monkey can turn to eating lichen, however, the population studied here in this lichen-absent area have adapted to their cool deciduous habitat by instead consuming buds and bark. Carbohydrate and energy rich foods appear to be the critical resources required for the persistence of this species in temperate habitat. The dietary flexibility of these monkeys, both among seasons and populations, likely contributes to their wide distribution over a range of habitats and environments.

Section: Discussionmentioning

confidence: 99%

Seasonal variation in diet and nutrition of the northern‐most population of Rhinopithecus roxellana

Hou

et al. 2018

“…A key first step for habitat restoration and conservation planning is determining which native tree species best fit the dietary and nutritional needs of the local animal community (Oliveira, Neves, Raboy, & Dietz, 2011; Sakamaki, Enari, Aoi, & Kunisaki, 2011). Currently, most of R. strykeri 's remaining habitat is located outside of protected areas where large‐scale deforestation has led to forest fragmentation and population isolation, which makes habitat restoration critically important (Ren et al, 2017).…”

Section: Discussionmentioning

confidence: 99%

Section: Recommendations For In and Ex-situ Conservationmentioning

confidence: 99%

Cafeteria‐style feeding trials provide new insights into the diet and nutritional strategies of the black snub‐nosed monkey (Rhinopithecus strykeri): Implications for conservation

Yang

Garber

et al. 2020

Anthropogenic changes and fragmentation of natural habitats often exert a negative effect on resource availability and distribution, and the nutritional ecology and feeding behavior of nonhuman primates. The goals of this study are to examine food choice and to identify the nutritional profile of foods consumed by the Critically Endangered black snub‐nosed monkey (Rhinopithecus strykeri). To accomplish our study goals, we presented cafeteria‐style feeding trials of fresh food items collected in the home range of wild black snub‐nosed monkeys to the only two captive R. strykeri, and compared the nutritional profiles of the leafy foods (buds, young, and mature leaves, 100 items from 70 plant species) selected with those avoided (54 items from 48 plant species). Overall, the results indicate that captive R. strykeri selected foods that were higher in moisture (Mo; 77.7%), crude protein (CP; 21.2%), total nonstructural carbohydrates (TNC; 34.9%), and phosphorus (P; 0.37%) while tending to avoid foods with a neutral detergent fiber (NDF) content of greater than 46.8%. Leaves collected in autumn and selected by the monkeys were characterized by a slightly higher amount of metabolizable energy (ME) than those rejected (1,350 kJ/100 g vs. 1,268 kJ/100 g). In contrast, the protein content of foods collected and consumed during the spring was greater (22.9%) than in autumn (16.4%). Random Forests modeling, an ensemble learning method, indicated that the proportion of Mo, NDF, ME, CP, P, and TNC were among the most important factors in predicting which items were consumed by the captive R. strykeri during spring and autumn. On the basis of the nutritional profile of foods consumed across the two seasons, we identified 18 nutrient‐rich native plant species that we recommend for use in ex‐ and in‐situ conservation management and reforestation programs to provide long‐term access to a nutritionally adequate diet.

“…In recent decades, there has been no large‐scale population culling; therefore, the population statistics and home ranges were free from artificial impacts during the study period. The dominant foods of these macaques during snowfall seasons are the bark and buds of deciduous broadleaf trees [Enari & Sakamaki, ; Sakamaki et al, ], and, particularly, the bark and buds of shade‐intolerant shrub and vine species (i.e., heliophytes [Sakamaki et al, ]).…”

Section: Methodsmentioning

confidence: 99%

“…We evaluated the feeding behavior of macaques not by observing individual animals, but by recording external signs within transects. We used bite marks and stripped bark as the external signs [Enari & Sakamaki, ; Li et al, ; Sakamaki et al, ]. Macaques feed on only the cambium layer of bark or a part of buds, and therefore, these signs are unequivocally left on every woody plant foraged on by macaques.…”

Section: Methodsmentioning

confidence: 99%

Influence of Heavy Snow on the Feeding Behavior of Japanese Macaques (Macaca Fuscata) in Northern Japan

Enari

Sakamaki–Enari

2013

Self Cite

Natural disasters can degrade primate habitat and alter feeding behavior. Here, we examined the influence of unusually heavy snow on diet and feeding-site use by Japanese macaques (Macaca fuscata) in northern Japan. To compare the winter-feeding behavior under different snow conditions, we recorded the plant species foraged on by macaques in multiple transects of the Shirakami Mountains from 2008 to 2012 (excluding 2011). We used cluster analysis to describe foraged plant assemblages, and applied multiple dimensional scaling and decision tree modeling to evaluate annual variation in feeding-site use by macaques. Our cluster analysis revealed five types of foraged plant assemblages. The proportion of each type present in transects varied considerably across the years, indicating that the diet of macaques in heavy snow conditions was influenced more by resource accessibility than by preference. Multiple dimensional scaling and decision tree modeling demonstrated that heavy snow conditions restricted feeding-site use. Moreover, the distribution of refuges relative to severe external ambient environments was a stronger limiting factor for feeding-site use than was the availability of food resources. While most primate species facing unexpected starvation employ risk-prone foraging tactics (i.e., choosing the option with higher pay-off by accepting risk), Japanese macaques have a tendency to adopt risk-averse foraging behavior (i.e., minimizing energy loss when searching for preferred diet items under long-lasting heavy snow conditions), because winters with temperatures below freezing have higher thermoregulatory costs.