Seasonal energy utilization in bamboo by the red panda (Ailurus fulgens)

Seasonal energy intake and digestion of bamboo by red pandas were measured in energy balance trials at the field station at an altitude of 3,100 m in Yele Natural Reserve, Mianning County of Sichuan Province, Peoples Republic of China. Two‐week trials were conducted at monthly intervals by feeding animals with only natural bamboo browse, Bashania spanostachya, from May to November 1995. Results demonstrated that energy intake, digestible energy, and digestibility differed significantly among seasons and diets. Energy digestibilities were high in summer‐autumn, intermediate in spring, and low in winter. These variations correlated positively with the nutrient contents of bamboo. The daily metabolic energy requirement measured varied from 2,603.3 kJ in the spring to 3,139.8 kJ in the summer‐autumn to 2,740.8 kJ in the winter. The results also showed that shoots were more easily digested than leaves and exhibited the highest digestibility. Restricted by the capacity of digestive tracts, red pandas poorly utilized the energy provided by bamboo as indicated by the lower energy digestibility (averaging 26.47% for leaves and 44.08% for shoots among the seasons). To fulfill their daily energy requirements, red pandas ingested a large amount of energy from bamboo leaves, which varied from 10,145.8 kJ in the spring, 12,045.1 kJ in the summer‐autumn, and 12,276.9 kJ in the winter to maximize the rate of energy intake. Zoo Biol 19:27–33, 2000. © 2000 Wiley‐Liss, Inc.     

Use of space, activity patterns, and foraging behavior of red howler monkeys (Alouatta seniculus) in an Andean forest fragment in Colombia

Howler monkeys are among the most studied primates in the Neotropics, however, behavioral studies including estimation of food availability in Andean forests are scarce. During 12 months we studied habitat use, behavior, and feeding ecology of two groups of red howler monkeys (Alouatta seniculus) in an isolated fragment in the Colombian Andes. We used a combination of focal animal and instantaneous sampling. We estimated fruit production (FP) using phenology transects, and calculated young leaf abundance by observing marked trees. The home range area used by each group was 10.5 and 16.7 ha and daily distances traveled were 431 ± 228 and 458 ± 259 m, respectively. We found that both groups spent most of their time resting (62–64%). Resting time did not increase with leaf consumption as expected using a strategy of energy minimization. We did not find a relationship between daily distances traveled and leaf consumption. However, howlers consumed fruits according to their availability, and the production of young leaves did not predict feeding time on this resource. Overall, our results are similar to those found on other forest types. We found that despite limited FP in Andean forests, this did not lead to a higher intake of leaves, longer resting periods, or shorter traveling distances for red howlers. Am. J. Primatol. 73:1062–1071, 2011. © 2011 Wiley‐Liss, Inc.     

A bioeconomic study on a provisioned troop of Japanese monkeys (Macaca fuscata fuscata) at koshima islet,Miyazaki

The natural and provisioned (wheat) food intake of the Japanese monkeys on Koshima was measured by direct observation. It was found that the portion of wheat consumed reflects such social structures in Japanese monkeys as (a) the structure of cocentric circles composed of several classes, (b) female ranking orders, (c) social strictness in breeding or non-breeding seasons. The natural food intake forIcho (2–3 years old female) was estimated for three seasons (April, September and December) during 1971. Her daily caloric intake was estimated from a quantitative list of natural foods eaten and the quantity of wheat eaten by multiplying the appropriate caloric values, and digestibility of 70%. The kcal day per values were 411 in spring, 522 in summer and 559 in winter. Her daily energy consumption (DEC) was estimated to be 398, 423, and 447 kcal/day in the respective seasons derived from the equation DEC =153W^2/3 which was obtained from data on activity telemetry and basal metabolic rates. The two spring values are in agreement. The summer and winter values show considerable differences. The dependency on wheat was calculated for individuals of various ages and sexes. The dependency of juveniles (60%) is about double that of ordinary females (25%). The Koshima troop is largely dependent on the evergreen broad leaves through all seasons. The increase of the number of females was cumulatively simulated assuming constant age-specific fecundity and mortality. There appeared one stagnated period of increase during the years 1961–1964 due to external factors. It will be a future problem to relate the quality of nutrition to reproductive performance.     

Food selection by black colobus monkeys (Colobus satanas) in relation to plant chemistry*

Black colobus monkeys (Golobus salanas) in the Douala-Edea Reserve, a rain-forest on the coast of Cameroon, have been shown to avoid young and mature leaves of most of the common plants in their habitat and to feed disproportionately heavily on leaves of rare plants. The proportion of leaves in the diet was low compared to most colobines studied, and the monkeys spent over half their feeding time eating seeds. Patterns of food selection were analysed in relation to distribution of nutrients, digestion–inhibitors and toxins in the vegetation. Colobw satanas select food items that are rich in mineral nutrients and nitrogen and low in content of the general digestion-inhibitors, lignin and tannin. They achieve this in the following ways: (i) by feeding preferentially on young leaves, which have higher nutrient content and lower contents of digestion-inhibitors than mature leaves; (ii) by eating those mature leaves with highest nument content relative to content of digestion-inhibitors; and (iii) by eating seeds, which are sources of readily available energy and which, as an item class, are less rich in digestion-inhibitors. Seeds at Douala-Edea appear to contain Ins nitrogen than leaves and C. satanas selects those seeds with highest nitrogen content. It is suggested that seed-feeding may be facilitated by the ability of the forestomach flora of these ruminant-like monkeys to detoxify some of the secondary compounds contained in seeds. Avoidance of most unused young and mature leaf items is correlated with a low nutrienudigestion-inhibitor ratio; avoidance of most unused seeds could be accounted for by their low nitrogen contents. Most items whose avoidance could not be explained in terms of these major constraints on food selection possess secondary compounds likely to be toxic. It is proposed that relative importance of digestion-inhibitors, low nutrient content and toxins as constraints on food selection by generalist herbivores will vary greatly among forests with different nutrient and secondary chemistry profiles.     

The diet and feeding behavior of the silver leaf monkey (Trachypithecus auratus sondaicus) in Indonesia

I describe the diet and feeding behavior of silver leaf monkeys (Trachypithecus auratus sondaicus) in the Pangandaran Nature Reserve, West Java, Indonesia, and compare a group living in old secondary rain forest with a group living in mixed plantation/secondary forest to determine intraspecific variation in feeding behavior and the importance of the plantation species in the diet of the monkeys. Young leaves and leaf buds made up slightly less than half of their diets, with both groups showing a preference for a few species when seasonally available. Fruits and flowers of a few species were also preferentially selected when available. These included sweet, fleshy fruits, which most other colobines tend to avoid. Young leaf intake was greatest in months when fruit intake was low. Mature leaves were rarely eaten. Both groups spent approximately 20% of feeding time foraging on Moraceae species. Differences in the diet of the two groups were related largely to differences in vegetational composition and the availability and abundance of food items for the species common to both sites. Teak (Tectona grandis) was the top food species of the group living in mixed plantation/secondary forest, with the midribs of young leaves preferentially selected. Young leaves ofT. grandis, available throughout the study, provided a staple food and were eaten when preferred foods were scarce. More favored food items were available to the group living in old secondary forest, though none was a staple food.     

Food and nutritional condition of free ranging Japanese monkeys on Koshima Islet during winter

A female with infant was chosen as material for study in an attempt to assess the nutritional condition of free ranging Japanese monkeys during winter. Her daily food composition, dry weight intake and nutritional (protein, lipid, carbohydrate, ash and calorie) intake were measured monthly (October to March). About 90% and 8% of the autumn diet consisted of fruits and invertebrate animals, respectively, while 70% of the winter diet (February) consisted of leaves of evergreen trees. Comparing the daily protein intake of this focal female with the requirement level estimated from references, only October and November represented months fulfilling this level. Also, there was a remarkable decrease in lipid intake towards winter. These results coincided well with the observed body weight loss in the female and the increasing feeding activity of her baby towards winter. It is suggested that such seasonal malnutrition of the mother might affect population parameters such as the infant mortality.     

The feeding ecology and activity budget of proboscis monkeys

A group of proboscis monkeys (Nasalis larvatus) consisting of an alpha‐male, six adult females, and several immatures was observed from May 2005–2006. We collected over 1,968 hr of focal data on the adult male and 1,539 hr of focal data on the six females in a forest along the Menanggul River, Sabah, Malaysia. Availability and seasonal changes in plant species consumed by the focal monkeys were determined by vegetation surveys carried out across an area of 2.15 ha along 200–500 m trails in riverine forest. A total of 188 plant species were consumed by the focal monkeys. The activity budget of members of our study group was 76.5% resting, 19.5% feeding, and 3.5% moving. Young leaves (65.9%) and fruits (25.9%) accounted for the majority of feeding time. Over 90% of fruit feeding involved the consumption of unripe fruits and in the majority of case both the fruit flesh and seeds were eaten. Although fruit eating was rare in some months, during other times of the year time fruit feeding exceeded the time devoted to young leaves. We found that monthly fruit availability was positively related to monthly fruit eating and feeding activity, and seasonal fluctuations in dietary diversity were significantly affected by fruit eating. These results suggest that fruit availability and fruit‐eating behaviors are key factors that influence the activity budget of proboscis monkeys. Earlier assumptions that colobine monkeys are obligate folivores do not apply well to proboscis monkeys and certain other colobines. Our findings may help contribute to a better understanding of the dietary adaptations and feeding ecology of Asian colobines. Am. J. Primatol. 71:478–492, 2009. © 2009 Wiley‐Liss, Inc.     

Food selection by two South-east Asian colobine monkeys (Presbytis rubicunda and Presbytis melalophos) in relation to plant chemistry

The diets of the banded leaf monkey ( Presbytis melalophos ) at Kuala Lompat in the Krau Game Reserve of West Malaysia and the red leaf monkey ( Presbytis rubicunda ) in Sepilok Virgin Jungle Reserve, Sabah, East Malaysia have been examined in relation to plant chemistry. Both monkeys spent about half their time eating foliage, and about half their time eating fruits and seeds. They both favoured leaves with high digestibility (due to relatively low levels of fibre) and high levels of protein, a combination found predominantly in young leaves and some flowers. The monkeys appeared to favour seeds and fruits with high concentrations of storage carbohydrates or fats, but not those rich in simple sugars. Selection of seeds and fruits was not correlated with protein content.
An analysis of the fibre and protein contents of foods showed that, on an annual basis, the two monkeys achieved a comparable intake for both items. However, these diets were obtained in radically different ways. Presbytis melalophos was able to eat foliage from many of the common tree species in its home range, whereas P. rubicunda relied on rare trees and lianas. This difference is attributed to the very high density of Dipterocarpaceae at Sepilok, a tree family that provides little food for colobines. The rarity of P. rubicunda's food plants at Sepilok is considered to be the main reason for the greater home range size and lower population density in comparison to P. melalophos.
Finally, the biochemical profiles of the young leaf diet of these two monkeys were compared with previously published information on two African and one south Indian colobines. In many respects the intake of supposed critical components, protein and fibre, showed marked similarities between different animals, considering contrasts in their habitats.     

Use of leaf resources by howling monkeys (Alouatta palliata) and leaf-cutting ants (Atta cephalotes) in the tropical rain forest of Los Tuxtlas,Mexico

Use of leaf resources by a troop of howling monkeys and two colonies of leaf cutting ants was studied for an annual cycle in the rain forest of Los Tuxtlas, Mexico. Howling monkeys spent half their annual foraging time feeding on leaves; leaf-cutting ants spent at least 80% of their recorded foraging time harvesting leaves. Both herbivores preferred young leaves over nature ones, and chemical analysis showed that the protein: fibre ratio of the leaves used was correlated with these preferences. Howling monkeys used 34 tree species as leaf sources. Leaf-cutting ants used 40 plant species of which 38 were trees. Eighteen species used by Alouatta were also used by Atta; species of Moraceae and Lauraceae were among the most important in their foraging preferences. The plant species used by monkeys and ants occurred at low densities (? 4.0 ind/ha). The seasonal production of leaves, the high density of leaf-cutting ant colonies at the study site, and the high amounts of young foliage harvested by the ants from tree species, and individual trees used by howling monkeys as sources of young leaves suggest that the foraging activities of Atta may represent a significant pressure upon leaf resources available to Alouatta.     

Fallback Foods of Red Leaf Monkeys (Presbytis rubicunda) in Danum Valley, Borneo

Animals in Southeast Asia must cope with long periods of fruit scarcity of unpredictable duration between irregular mast fruiting events. Long-term data are necessary to examine the effect of mast fruiting on diet, and particularly on the selection of fallback foods during periods of fruit scarcity. No such data is available for colobine monkeys, which may consume substantial amounts of fruits and seeds when available. We studied the diet of red leaf monkeys (Presbytis rubicunda, Colobinae) in Danum Valley, Sabah, northern Borneo, using 25 mo of behavioral observation, phenology and vegetation surveys, and chemical analysis to compare leaves eaten with nonfood leaves. The monkeys spent 46% of their feeding time on young leaves, 38% on seeds, 12% on whole fruits, 2.0% on flowers, 1.0% on bark, and 1.2% on pith. They spent more time feeding on seeds and whole fruit when fruit availability was high and fed on young leaves of Spatholobus macropterus (liana, Leguminosae) as fallback foods. This species was by far the most important food, constituting 27.9% of the total feeding time, and the feeding time on this species negatively correlated with fruit availability. Consumed leaves contained more protein than nonconsumed leaves, and variation in time spent feeding on different leaves was explained by their abundance. These results suggest that red leaf monkeys show essentially the same response to the supra-annual increase in fruit availability as sympatric monogastric primates, increasing their seed and whole-fruit consumption. However, they depended more on young leaves, in particular Spatholobus macropterus, as fallback foods during fruit-scarce periods than did gibbons or orangutans. Their selection of fallback food appeared to be due to both nutrition and abundance.     

Resource use by howler monkeys (Alouatta palliata) in the rain forest of Los Tuxtlas,Veracruz, Mexico

The feeding preferences of howler monkeys at their northernmost distribution in the Neotropics are reported for an annual cycle. A remarkable selectivity for 27 species representing 15 families was observed. The Moraceae and Lauraceae plant families were the most important in the diet. The howlers spent an almost equal proportion of their feeding time eating leaves and fruit, and displayed a marked preference for young leaves and mature fruit. The consumption of different plant parts was markedly seasonal and the howlers’ ranging behavior was closely associated with the availability of young leaves and mature fruit. Their home range was unusually large (ca. 60 ha) for howlers and the food species exploited occur at very low densities (93%, ≤ 4 ind/ha). They chose food items richer in protein and energy. Alkaloid compounds, present in some of the leaves, play a secondary role in their dietary selectivity.     

Bioenergetics of Japanese monkeys (Macaca fuscata) on Kinkazan Island during winter

An adult female Japanese monkey was chosen as a focal animal in order to assess the nutritional condition of the species during winter on Kinkazan Island, which is covered by deciduous forest of the cool temperate zone. Five whole-day-long observations were performed at the end of November (late autumn) and also at the end of February (late winter). In November, the daily energy intake and protein intake were estimated to be 1,449 kcal and 36 g, respectively: both satisfied the intake requirement even in view of a digestibility of 55%. These findings suggest that the focal animal could accumulate body fat in November. In contrast, in February, the daily energy intake and protein intake were estimated to be 556 kcal and 12 g, respectively: both did not satisfy the intake requirement in view of a digestibility of 55%. These findings suggest that the focal animal consumed accumulated body fat in February. Various data for food intake, nutritional content, etc. on Kinkazan were compared with those on Koshima, which is covered by evergreen forest of the warm temperate zone. The nutritional intake in February on Kinkazan was much smaller than that in November on Kinkazan as well as those in November and February on Koshima. The small intake of the former appeared to be strongly influenced by the sign ficantly lower speed of dry weight intake, which derived partly from the significantly lighter unit weight of the food items (e.g., buds ofZanthoxylum piperitum, Castanea crenata, andCornus macrophylla; leaves and stems ofOplismenus uadulatifolius andZoysia japonica). The monkeys on Kinkazan Island increased their food diversity, shortened their daily travel distance, and avoided repeated use of sites within their home range to offset the deterioration of the food quality in February.     

Feeding strategies of Japanese monkeys against deterioration of habitat quality

Field observations of the feeding behaviour of Japanese monkeys were carried out from autumn to winter on Kinkazan Island which is covered with cool temperate forest. As a result, the following two points became clear: (1) the available food items were fixed for a long time; and (2) the habitat quality deteriorated monotonously because the monkeys themselves or their competitors, such as wild mice, utilized the food resources. Against the decrease in food intake caused by this deterioration of the habitat quality, the monkeys controlled the decrease in food intake by employing the following strategies: (1) they recovered their feeding speed by exploiting new food patches (patch-increase strategy); (2) they extended the time spent on feeding (time-extension strategy); and (3) they changed their food (food-change strategy). The former two strategies operated earlier than the third one.     

Effects of habitat differences on feeding behaviors of Japanese monkeys: Comparison between Yakushima and Kinkazan

Feeding behaviors of Japanese monkeys (Macaca fuscata) were compared between a warm temperate habitat (Yakushima Island: 30°N, 131°E) and a cool temperate habitat (Kinkazan Island: 38°N, 141°E). The composition of diet and the activity budget in the two habitats were very different. Time spent feeding on Kinkazan Island was 1.7 times that on Yakushima Island. Two factors seem to be responsible for these: (1) the energy required for thermoregulation of monkeys on Kinkazan Island is greater than that on Yakushima Island; and (2) the food quality, which affects the intake speed of available energy, is lower on Kinkazan Island. However, monkeys in both habitats increased their moving time and decreased their feeding time when they fed on foods of relatively high quality. Such foraging strategies are predicted by optimal foraging models. Time spent social grooming on Yakushima Island was 1.9 times that on Kinkazan Island, although there were slight seasonal changes in both areas. The difference in time spent social grooming might be explained by the overall difference in feeding time and day length between the two habitats.     

Leaves of Japanese oak (Quercus mongolica var. crispula) mitigate photoinhibition by adjusting electron transport capacities and thermal energy dissipation along the intra-canopy light gradient

We investigated the morphological and physiological acclimation of leaves grown within a canopy of Japanese oak tree (Quercus mongolica var. crispula) in terms of the susceptibility to photoinhibition under various growth light conditions. The maximum rates of photosynthesis (P(max) ) and electron transport (ETR(max) ) were higher in mature leaves grown under stronger light with higher area-based leaf nitrogen (N) content closely associated with higher leaf mass per area. The net photosynthetic (P(n) ) and electron transport (ETR) rates corresponding to the daily peak photosynthetic photon flux density (PPFD(max) ) during leaf maturation were almost comparable to P(max) and ETR(max) , respectively. Conversely, P(n) and ETR at the daily average PPFD (PPFD(avg) ) were substantially low in shade-grown leaves when compared with P(max) and ETR(max) . The susceptibility to photoinhibition at PPFD(max) , i.e. at sunflecks for the shade-grown leaves, was assessed by the rate of excess energy production. Although sun leaves showed higher rates of electron transport and thermal energy dissipation than shade leaves under PPFD(max) conditions, the rate of excess energy production was almost constant across shade to sun leaves. The shade leaves of the Japanese oak grown within a crown were suggested to adjust their N investment to maintain higher photosynthetic capacities compared with those required to maximize the net carbon gain, which may facilitate the dissipation of the excessive light energy of sunflecks to circumvent photoinhibition in cooperation with thermal energy dissipation.     

Influence of fruit availability on macronutrient and energy intake by female chimpanzees

Daily energy intake of adult female mammals is influenced by environmental conditions and physiological requirements, including reproduction. We examined the effects of fruit availability on macronutrient and metabolisable energy (ME) intake by adult female chimpanzees (Pan troglodytes schweinfurthii) of the Kanyawara community in Kibale National Park, Uganda, from January 2014 through June 2015. Drupe fruits were abundant for 4 months, whereas the other 14 months were dominated by fig fruits. The mean daily intake of food (dry matter) and ME did not differ between drupe‐months and fig‐months. However, foraging costs were higher during fig‐months, as indicated by a 20% increase in feeding time. Furthermore, during drupe‐months female chimpanzees ingested more water‐soluble carbohydrates and lipids, and less available protein and neutral detergent fibre. Although ME intake did not differ consistently between drupe‐months and fig‐months, they consumed more on days when ripe fruit dominated the diet than when leaves and pithy stems dominated the diet. Our data suggest that differences in diet quality between drupes and figs can have important effects on frugivore foraging and that they influence net energy gain more by their effects on macronutrient composition or foraging cost than by their direct impact on energy intake.     

Daily feeding rhythm in proboscis monkeys: a preliminary comparison with other non-human primates

In non-human primates, the daily feeding rhythm, i.e., temporal fluctuation in feeding activity across the day, has been described but has rarely received much analytical interpretation, though it may play a crucial part in understanding the adaptive significance of primate foraging strategies. This study is the first to describe the detailed daily feeding rhythm in proboscis monkeys (Nasalis larvatus) based on data collected from both riverbank and inland habitats. From May 2005 to May 2006, data on feeding behavior in a group of proboscis monkeys consisting of an alpha-male, six adult females and immatures was collected via continuous focal animal sampling technique in a forest along the Menanggul River, Sabah, Malaysia. In both the male and females, the highest peak of feeding activity was in the late afternoon at 15:00–17:00, i.e., shortly before sleeping. The differences in the feeding rhythm among the seasons appeared to reflect the time spent eating fruit and/or the availability of fruit; clearer feeding peaks were detected when the monkeys spent a relevant amount of time eating fruit, but no clear peak was detected when fruit eating was less frequent. The daily feeding rhythm was not strongly influenced by daily temperature fluctuations. When comparing the daily feeding rhythm of proboscis monkeys to that of other primates, one of the most common temporal patterns detected across primates was a feeding peak in the late afternoon, although it was impossible to demonstrate this statistically because of methodological differences among studies.     

Maximum daily energy intake: it takes time to lift the metabolic ceiling

Conventionally, maximum capacities for energy assimilation are presented as daily averages. However, maximum daily energy intake is determined by the maximum metabolizable energy intake rate and the time available for assimilation of food energy. Thrush nightingales (Luscinia luscinia) in migratory disposition were given limited food rations for 3 d to reduce their energy stores. Subsequently, groups of birds were fed ad lib. during fixed time periods varying between 7 and 23 h per day. Metabolizable energy intake rate, averaged over the available feeding time, was 1.9 W and showed no difference between groups on the first day of refueling. Total daily metabolizable energy intake increased linearly with available feeding time, and for the 23-h group, it was well above suggested maximum levels for animals. We conclude that both intake rate and available feeding time must be taken into account when interpreting potential constraints acting on animals' energy budgets. In the 7-h group, energy intake rates increased from 1.9 W on the first day to 3.1 W on the seventh day. This supports the idea that small birds can adaptively increase their energy intake rates on a short timescale.     

Relevance of chronotype for eating patterns in adolescents

During adolescence, a shift from morningness to eveningness occurs, yet school continues to start early in the morning. Hence, adolescents are at risk for social jetlag, i.e. a discrepancy between biological and social timing. It remains to be determined whether chronotype associates with daily and daytime-specific eating patterns during this potentially critical period. Therefore, the aim of the present study was to investigate whether chronotype is decisive for daily eating patterns [total energy intake (TEI, kcal), total macronutrient intake (% of TEI), eating occasion frequency (n/day), meal frequency (n/day), snack frequency (n/day), duration of nightly fasting], or daytime-specific eating patterns [morning (before 11 am) energy intake (% of TEI), morning macronutrient intake (% of morning energy intake), regular breakfast skipping (no morning energy intake at least on 2 of 3?days, yes/no), evening (after 6 pm) energy intake (% of TEI), evening macronutrient intake (% of evening energy intake), regular dinner skipping (no evening energy intake at least on 2 of 3?days, yes/no)] in German adolescents. Chronotype was assessed by use of the Munich Chronotype Questionnaire and is defined as the midpoint of sleep corrected for sleep-debt accumulated over the workweek (the later the midpoint of sleep, the later the chronotype). A total of 223 participants (10–18?years) provided 346 questionnaires and concurrent 3-day weighed dietary records. Associations between chronotype and eating patterns were analyzed cross-sectionally using multivariable linear and logistic mixed-effects regression models. Adolescents with earlier and later chronotypes did not differ in their daily eating patterns. With respect to daytime-specific eating patterns, 1?h delay in chronotype was associated with 4.0 (95% CI 2.5–6.6) greater odds of regular breakfast skipping (p < 0.0001). In addition, later chronotype was associated with higher evening energy intake (p = 0.0009). In conclusion, our data show that a later chronotype among adolescents is associated with a shift of food consumption toward later times of the day. Hence, adolescents’ eating patterns appear to follow their internal clock rather than socially determined schedules.     

Nutrient Balancing by Captive Golden Snub-Nosed Monkeys <Emphasis Type="Italic">(Rhinopithecus roxellana</Emphasis>)

An organism’s fitness is tied closely to its ability to obtain food. However, many foods are nutritionally suboptimal on their own, forcing an individual to develop a feeding strategy that actively manages both type and amount of food consumed. Animals in captivity are additionally limited to human provisioned diets, which may be nutritionally inadequate and negatively affect behavior and health. We studied the nutritional intake of captive golden snub-nosed monkeys (Rhinopithecus roxellana) at two locations in China (132 days of continuous, sunrise to sunset focal samples of 7 individuals at each site) and used the Geometric Framework for nutrition to identify their feeding strategy and evaluate diet variation across sites, seasons, and age–sex classes. Captive golden snub-nosed monkeys had a mean nutrient intake of 75% carbohydrates (15% neutral detergent fiber, 60% total nonstructural carbohydrates), 12% fat, and 13% protein (by energy) that differed by location and season owing to differences in the type and amount of food items offered and consumed. Intake at one location differed from that of wild golden snub-nosed monkeys, suggesting that the captive diet was inadequate. These results highlight the importance of developing nutritionally adequate diets for captive animals based on an understanding of their nutritional requirements.