Foraging,Food Choice,and Food Processing by Sympatric Ripe-Fruit Specialists: <Emphasis Type="Italic">Lagothrix lagotricha poeppigii</Emphasis> and <Emphasis Type="Italic">Ateles belzebuth belzebuth</Emphasis>

Studies of interspecific competition and niche separation have formed some of the seminal works of ecology. I conducted an 18-mo study comparing the feeding ecologies of 2 sympatric, closely-related ripe-fruit specialists, Humboldt's woolly monkeys (Lagothrix lagotricha poeppigii), and the white-bellied spider monkeys (Ateles belzebuth belzebuth) in Amazonian Ecuador. Woolly monkeys in the terra firme forest live at roughly triple the density of spider monkeys (31 versus 11.5 animals/km²). Woolly monkeys spend 17% of their time foraging, while spider monkeys spend only 1% of their time foraging. Spider monkeys alone fed on soil and termitaria, which are rich in phosphorus. Woolly monkeys are not hard-fruit specialists. Their fruit diet is significantly more diverse than that of spider monkeys. Dietary overlap between the 2 species is high, yet each specializes to some degree on a different set of fruit resources. Woolly monkeys visit more food sources per unit of time, feed lower in the canopy, visit more small food patches, and prey on more seeds. Spider monkeys feed on fewer, richer food sources and are more than twice as likely to return to a particular fruit source than woolly monkeys are. Spider monkeys maximize fruit pulp intake, carrying more intact seeds in their guts, while woolly monkeys minimize seed bulk swallowed through more careful food processing. Surprisingly, several preferred spider monkey foods with high fat content and large seeds are avoided by woolly monkeys. I outline the different ecological dimensions involved in niche separation between the 2 species and discuss the possible impetus for their evolutionary divergence.     

Diet and Feeding Ecology of Woolly Monkeys in a Western Amazonian Rain Forest

I investigated the diet and feeding ecology of two social groups of woolly monkeys (Lagothrix lagotricha poeppigii) in Yasuní National Park, Ecuador between April 1995 and March 1996. Woolly monkeys in Yasuní were predominantly frugivorous, with fruits comprising ca. 77% of the yearly diet; the next most common food type in the diet was insect and other animal prey. The fruit diet of woolly monkeys in Yasuní is the most diverse yet recorded for any ateline primate, including spider monkeys (Ateles), which are often regarded as ripe fruit specialists: 208 distinct morphospecies of fruits were consumed by woolly monkeys either during the study or during several preceding months of pilot work. Nonetheless, close to one-third of the yearly diet came from just 3 plant genera—Inga, Ficus, and Spondias—and only 20 genera each contributed to 1% of the diet. For one study group, the proportion of ripe fruit in the diet each month was correlated with the habitat-wide availability of this resource, a pattern evidenced by several other ateline species. However, the relationship was not apparent in the second study group. The modal party size for feeding bouts on all food types was a single monkey, and, contrary to reports for other atelines, neither feeding party size nor the total number of feeding minutes that groups spent in food patches was well predicted by patch size. Both results highlight the independent nature of woolly monkey foraging. Given that woolly monkeys and closely-related spider monkeys focus so heavily on ripe fruits, their very different patterns of social organization are intriguing and raise the question of just how their ecological strategies differ. Two important differences appear to be in the use of animal prey and in the phytochemical composition of the ripe fruits that they consume: spider monkeys rarely forage for animal prey, and woolly monkeys seldom consume the lipid-rich fruits that are an important part of spider monkey diets.     

Activity and ranging patterns of Colombian woolly monkeys in north-western Amazonia

In this study, I revise three aspects of the socioecology of woolly monkeys (genus Lagothrix) that might give us a better understanding of the patterns found in this species: (1) the association between temporal variation in fruit abundance and diet, activity, and ranging patterns; (2) the individual trade-offs associated with living in small or large groups, and (3) the relationship between social dominance and foraging success. Using behavioral and ecological data collected during 3 years in Tinigua Park, Colombia, I found that woolly monkeys tend to avoid open-degraded forests, where fruit production is generally lower than it is in mature forests. Diet and activity budgets were highly associated with temporal patterns of fruit production. Daily path length was positively correlated with group size and monthly fruit abundance, and negatively correlated with habitat quality. I found differences in activity budgets and the diet preferences of different age/sex classes. For example, adult males rest more and juveniles play more than other classes. Juveniles and adult females without infants look for arthropods more often than adult males and females with young infants, who showed the highest frequencies of fruit feeding. Dominant adult males were not consistently the most efficient foragers on fruits according to two different indexes. Most of these results are consistent with the expectations from strong intra-group competition for resources. However, females with infants received benefits during feeding similar to those of dominant adult males, which may be mediated by differential aggression from males to other group members (juveniles and females without infants).     

Time Allocation Patterns of Lowland Woolly Monkeys (Lagothrix lagotricha poeppigii) in a Neotropical Terra Firma Forest

We investigated the time allocation decisions of lowland woolly monkeys (Lagothrix lagotricha poeppigii) in a terra firma forest in eastern Ecuador where they occur sympatrically with 9 other primate species. Woolly monkeys spent considerable amounts of time searching for and attempting to procure animal prey—roughly as much time as they spent consuming plant material: ripe fruits, leaves, and flowers. The amount of time spent foraging for animal prey is positively related to the habitat-wide availability of ripe fruits (the predominant component of the woolly monkey diet), and negatively related to both ambient temperature and the abundance of potential prey items in the habitat. Time spent resting showed exactly the opposite pattern with respect to these ecological variables. These results suggest that woolly monkeys follow an energy-maximizing strategy of food acquisition during times of fruit abundance—focusing on animal foods and perhaps laying down fat reserves to utilize when ecological conditions worsen—and follow an energy-minimizing strategy when fruit resources are scarce. Such a strong and seasonal commitment to animal prey foraging is unique among the ateline primates and is not ubiquitous even among lowland woolly monkeys. We suggest that this foraging strategy, and the greater intragroup cohesion that characterizes some populations of Lagothrix, are both opportunistic responses to regional differences in habitat quality. Identifying and accounting for such intraspecific variation should be a goal of any analysis of comparative socioecology.     

Ecological strategies of woolly monkeys (Lagothrix lagotricha) at Tinigua National Park,Colombia

Information on the use of space, activity patterns, diet, and social interactions were recorded for a group of woolly monkeys (Lagothrix lagotricha) during 13 months at Tinigua National Park, Macarena, Colombia. In this region, fruit abundance changes throughout the year with a peak during March–April (beginning of the rainy season) and less fruit during September-November (end of rainy season). Woolly monkeys spent most of their time in mature forest where fruit abundance is higher than in opendegraded or flooded forests. Changes in habitat used by monkeys were coupled with changes in fruit supply across vegetation types. On an annual basis, woolly monkeys spent 24% of point samples locomoting, 36% resting, 36% feeding, and 4% on other activities. However, these proportions varied across the year depending on fruit availability. Based on instantaneous samples, the diet consisted mostly of fruits (60%), arthropods (23%), vegetative parts and flowers (17%), and other items (1%). Non-lactating females and juveniles spent more time eating insects than adult males and lactating females; however, significant differences between classes were detected only during the period of fruit scarcity. These differences are probably due to the high extent to which non-lactating females and juveniles were excluded from fruiting trees by males. The high proportion of arthropods in their diet is unusual for primates with large body size and is a possible factor influencing group cohesiveness in woolly monkeys. © 1994 Wiley-Liss, Inc.     

Ranging behavior and foraging ecology of lowland woolly monkeys (Lagothrix lagotricha poeppigii) in Yasuní National Park,Ecuador

In a year-long study, I investigated the ranging behavior of lowland woolly monkeys (Lagothrix lagotricha poeppigii) in a terra firma rainforest in Yasuní National Park, Ecuador, and examined the relationship between ranging, diet, food availability, and food patch use for this population. In Yasuní the total home range sizes for two social groups were 124 and 108 ha, which are much smaller than has been reported previously for Lagothrix elsewhere in its geographic distribution. The mean yearly day range estimates for these same groups were 1,792 m and 1,878 m, which are well within the range of variation previously reported. Ranging behavior was not correlated with the current habitat-wide abundance of ripe fruit, which comprises 76.3% of the yearly diet for this population, but was associated with one measure of likely insect prey abundance and with the availability of immature fruits, a minimal part of the diet. Specifically, one study group moved significantly greater distances during months of high likely insect prey abundance and when immature fruits were abundant. The second study group also traveled farther when likely insect prey abundance was high and when immature fruits were abundant, although the latter relationship only approached significance. This group also devoted significantly more of its daily activity budget to travel during these times. These results indicate that variation in ripe fruit abundance makes no meaningful contribution to explaining variation in ranging behavior for this population of woolly monkeys. Instead, the results raise the possibility that some aspects of the ranging behavior of frugivorous primates may be related to the availability of alternative food sources, such as animal prey, or to monitoring the phenological status of important fruit trees, rather than simply reflecting the degree of intragroup feeding competition.     

Utilization of fruiting trees by monkeys as analyzed from feeding traces under fruiting trees in the tropical rain forest of Cameroon

Individual trees of the food species of monkeys were identified by placing plastic tapes with an identification number on them in the tropical rain forest of Cameroon, West Africa. In order to determine the use of the feeding trees by monkeys, the ground under each of the trees was checked at least once a week to see if there were any fallen fruits or traces of feeding on fruits. Some fruit species were not fed on by either monkeys or large arboreal squirrels. Among the food species common to both the monkeys and large squirrels, a larger proportion in terms of quantity in each species was mainly eaten by the monkeys except in the case of super-abundantly fruit producing species. The monkeys and large arboreal squirrels were well segregated in their diets. Larger proportions (more than 85% for most of the monkeys' major foods) of fruits of larger sizes were made to fall on the ground by the monkeys and squirrels. The monkeys displayed a tendency to visit fruiting trees rather evenly (even rate of visit = even frequency of visit/duration of fruiting) not ignoring any area of the home range, although a small difference in this tendency was observed between the two study periods, one an abundant season and the other a poor fruiting season. On average, one associated polyspecific group of monkeys encountered only 14 fruiting trees per day. On the other hand, fruits were available all around the year, as the fruiting periods of different tree species were widely distributed around the year, or the fruiting periods of some species were very long. Although the monkeys are able to depend heavily on fruits, the quantity of fruits is not so great. The population size of monkeys is well balanced with the available food supply in the tropical rain forest of West Africa.     

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.     

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.     

Seed dispersal versus seed predation: an inter-site comparison of two related African monkeys

C. pogonias and C. wolfi plant diets were studied in two sites, in Gabon and Zaire and compared with fruit availabilities. Monkeys in Gabon were found to be mainly fruit pulp-eaters while monkeys in Zaire were alternately seed-eaters, aril-eaters or leaf-eaters. These differences were related to differences in the availability of fruit categories: fleshy fruits were found to be much more abundant in Gabon than in Zaire forests. As a result, monkeys in Gabon were found to be mainly seed-dispersers while monkeys in Zaire were found, to a large extent, to be seed-predators. Results are discussed in terms of phenotypic flexibility in monkey feeding behavior, diversity of plant-monkey interactions, geographic variability of keystone plant resources, and their implications for forest management practices. The low availability of fleshy fruit species in Zaire is hypothezized to result from the poor soil conditions.     

Seasonal changes in food resource distribution and feeding sites selected by Japanese macaques on Koshima Islet,Japan

Feeding sites of Japanese macaques (Macaca fuscata) change according to seasonal fluctuations in food resource distribution. To examine what characteristics of food items affect feeding site selection, I describe herein the seasonal changes in food items, feeding sites, and food resource distributions of this species. Feeding behavior of monkeys and their food resource distributions were investigated on Koshima Islet, southern Japan, for four study periods (i.e., seasons) in 2002. Monkeys showed large variations in their diet between seasons. To weigh the relative influence of the distribution and abundance of food items on feeding site selection in each season, multiple regression analyses were performed by 100 m × 100 m grid. In the analyses, feeding time was a dependent variable and the abundance of staple food items, for which feeding time was over 5% in each season, in each grid square was an independent variable. There was no correlation between the resource distribution of most food items and the distribution of feeding time by monkeys in each season. Monkeys spent more feeding time where multiple staple food items were available. Food items that affected feeding site selection by monkeys had the following three characteristics: (1) clumped distribution, (2) seasonal availability, and (3) fruit. This suggests that monkeys are likely to select feeding sites to consume food items whose availability is limited temporally and spatially, which may enable them to simultaneously use other widely distributed, abundant food items efficiently.     

The influence of seed packaging and fruit color on feeding preferences of American robins

We investigated the role of seed packaging (division of total seed volume among individual seeds) and fruit color in determining feeding preferences of American Robins (Turdus migratorius). Experiments were conducted using artificial fruits with either 8 small plastic beads or a single large one with equivalent volume. Other fruit characters were held constant. As predicted, large seeds were voided rapidly by regurgitation, resulting in higher pulp consumption rates for large-seeded fruits than for small-seeded ones, whose seeds were passed through the gut. Most birds apparently used this difference in profitability as a choice criterion: four of seven preferred large-seeded fruits. That three individuals did not do so suggests that birds may differ in their ability to perceive minor differences in fruit profitability, or to use them as choice criteria. Pulp color was also important: blue fruits were preferred by all seven birds. This preference was surprising, since Robins commonly feed on red fruits in the field.     

Diet and feeding ecology of gray woolly monkeys (lagothrix lagotricha cana) in Central Amazonia: Comparisons with other Atelines

I studied gray woolly monkeys (Lagothrix lagotricha cana)in an undisturbed central Amazonian terra firme forest, near the headwaters of the Urucu river, Tefé, Amazonas, Brazil (5°50’S, 65°16’W). I report the diet and feeding ecology of a group of 39–41 individuals, based on systematic feeding observations obtained during 11 months. Woolly monkeys are primarily frugivorous; mature fruits and young seeds account for 83 and 7% of 3298 feeding records, respectively. On a seasonal basis, however, they relied heavily on young foliage (16%), seed-pod exudates (6%), and flowers (3%), particularly during the greatest annual period of ripe fruit scarcity, as determined by a phenological survey. Animals represent only 0.1% of their year-round diet, and they spent little time capturing arthropods and other prey items. Although at least 225 plant species, belonging to 116 genera and 48 families, are in their diet, the three top-ranking families (Moraceae, Sapotaceae, and Leguminosae) account for 43% of their food species and 63% of the time they spent feeding on a year-round basis. I compare the feeding ecology and diet of L. 1. canain the Urucu and other taxa of Lagothrixin upper Amazonia — the last large-bodied Neotropical primates to be studied — to those of other ateline genera: Atelesand Brachyteles. An erratum to this article is available at .     

Modeling dietary selectivity by Bornean orangutans: Evidence for integration of multiple criteria in fruit selection

Food patch visitation was compared to the availability of fruit patches of different species during 2 years in a Bornean lowland forest to examine orangutan (Pongo pygmaeus) diet selectivity. Feeding on both the pulp and the seeds of nonfig fruit varied directly with fruit patch availability, demonstrating preference for these foods over fig fruit or other plant parts (bark or leaves). Factors determining fruit selectivity rank were examined through multiple regression analysis. Modeling selectivity for 52 chemically unprotected primate-fruit pulp species revealed strong preferences for species of (i) large crop size (numbers of fruits ripening in an individual patch), (ii) high pulp weight/fruit, and (iii) high pulp mass per swallowed unit of pulp + seed, demonstrating orangutan sensitivity especially to patch size (g of pulp or total energy/patch) and perhaps to fruit handling time. Modeling selectivity for 18 fig species showed that 4 factors significantly influenced fig species rank: crop size, pulp weight/fruit, and 2 chemical variables, percentage digestible carbohydrate and percentage phenolic compounds in the fig fruit pulp. The selectivity rank based on the overall nutrient gain from feeding in the fruit patch (the product of the first 3 variables) is proportionally depressed by the percentage tannin content, demonstrating that orangutans integrate values for these variables in selecting fig patches. The conclusions from these results and from analysis of selectivity for seeds and for other fruit types are that orangutan foraging decisions are strongly influenced by the meal size expected from a feeding visit (i.e., by patch size), that tannins and other toxins deter feeding, and that the energy content, rather than the protein content, of foods is important in diet selection. The foraging strategy of orangutans is interpreted relative to these results and to Bornean fruiting phenology. By integrating spatial, morphometric, and chemical variables in analysis, this study is the first to demonstrate the application of foraging theory to separate out the key variables that determine diet selection in a primate. Multivariate analysis should routinely be applied to such data to distinguish among the many covarying attributes of food items and patches; inferences drawn in previous studies of primate diet selection, which ignore key spatial and morphological variables and rely on univariate correlations, are therefore suspect.     

Effects of Seed Dispersal by Three Ateline Monkey Species on Seed Germination at Tinigua National Park, Colombia

We examined the effect of seed ingestion by three ateline primates: woolly monkeys, Lagothrix lagothricha; spider monkeys, Ateles belzebuth; and, red howler, Alouatta seniculus on germination rates and latency periods of seeds of several plant species in Tinigua National Park, Colombia. We collected dispersed seeds from feces and control seeds from the parental trees and washed them for germination trials. For the majority of plants, dispersed seeds germinated as well or better than control seeds did. Although spider monkeys depend more heavily on fruits than the other monkey species do, they were not more efficient than howlers or woolly monkeys at improving germination rates. A considerable proportion of the seeds dispersed by howlers and woolly monkeys showed reduced latency periods to germination, but spider monkeys showed less effect on reducing germination time. This result may be related to longer gut retention times, but such a trend has not been observed in other primate species. We conclude that, like many other primates, ateline monkeys are effective seed dispersers in terms of their effects on the seeds they swallow because they rarely decrease their germination rates. We discuss problems that make interspecific comparisons difficult, such as inappropriate control seeds and differences associated with germination substrates, and we stress the importance of studying other components of seed dispersal effectiveness.     

Diet and Travel Costs for Spider Monkeys in a Nonseasonal, Hyperdiverse Environment

I studied the effects of a nonseasonal environment with a high diversity of plant species in a community of white-bellied spider monkeys (Ateles belzebuth belzebuth) in the Yasuní National Park, Ecuador. During 10 2-wk follows of focal individuals across 1 yr, I collected 1268 h of observation data on ranging and foraging. The environment had strong effects on both the foraging and ranging behavior of the monkeys. Yasuní spider monkeys are similar to spider monkeys in more seasonal environments in that ripe-fruit consumption dominates the diet. However, Yasuní spider monkeys exhibit an extremely diverse diet that parallels the variety of foods available to them, consuming more than 238 species of fruits. The impressive dietary variety increased even more with increased observation time, as I had not previously observed in the spider monkeys’ diet 40% of the fruit species the subjects consumed during the final follow. Ripe fruits remain the most important item in the diet year-round, supplemented with decayed wood or leaf flush. Local rarity of plant species means that fruiting patches are an average of 420 m apart, and mean patch residence times are short, only 8.1 min. Visits to an average of 11.5 feeding patches/d lead to a mean daily path length of 3311 m, longer than reported for any other Ateles species, and long compared to most other primate species. The long daily paths of Yasuní spider monkeys reflect travel costs resulting from foraging in a hyperdiverse nonseasonal environment.     

Phytophagous preferences of the multicolored Asian lady beetle (Coleoptera: Coccinellidae) for autumn-ripening fruit

The objective of this study was to assess the potential pest status of Harmonia axyridis (Pallas) on autumn-ripening fruit. In autumn, H. axyridis has been observed feeding on pumpkins, apples, grapes, and raspberries in Minnesota. To determine whether H. axyridis can inflict primary feeding damage to fruit (i.e., breaking the skin of the fruit), we conducted laboratory feeding experiments with undamaged pumpkins, apples, grapes, and raspberries. The only fruit that H. axyridis was able to damage directly was raspberry. Laboratory choice tests were conducted to determine whether H. axyridis exhibits a preference between damaged and undamaged fruit, between cultivars of fruit, and between sugar water and water alone. For all fruits tested, H. axyridis showed a preference for damaged fruits over undamaged fruits. H. axyridis also exhibited a strong preference for sugar water over water alone. However, few differences were exhibited in preference between cultivars of fruit. In autumn, it seems that H. axyridis is an opportunist, taking advantage of previously damaged fruit, caused by other agents.     

Fruit choice by red howler monkeys (Alouatta seniculus) in a tropical rain forest

This paper presents and discusses aspects of fruit selectivity by red howler monkeys (Alouatta seniculus) in relation with morphological characteristics of fruits. These data are used to provide an answer to the following questions: which are the fruit characteristics that lead fruit choice of howler monkeys and to what extent fruit characteristics play a role in seed dispersal by monkeys? The frugivorous diet of a troop of red howler monkeys was determined during a 2-year field study in French Guiana. The selection of fruit by howler monkeys was analyzed in relation to the fruit availability. Results showed that, although consumption followed availability, fruit species could be classified in three categories according to their selection ratio (percentage of consumption/percentage of abundance) as “high ranking,” “middle ranking,” and “low ranking” species. Also, the 97 species of fruit eaten by the monkeys were grouped according to the morphological characteristics thought to influence the monkeys' choice. This showed that howler monkeys consumed essentially fruits with juicy pulp, bright color, and a small number of well-protected seeds. Most of high ranking species had medium-sized fruits with yellow color, and low ranking species often had small fruits. However, howler monkeys are associated with the dispersal of seeds from fruit with a hard and indehiscent pericarp and/or large seeds, like those of the Sapotaceae family. Consequently, they can be considered as “specialized” frugivores for this fruit syndrome. © l996 Wiley-Liss, Inc.     

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.