Influence of Human Food Consumption on the Time Budget of Vervets

In nonhuman primate groups that utilize crop and food-raiding strategies, the inclusion of human food in the diet can have a pervasive impact on the activity budget. Human food is usually of higher quality and energy per unit than wild food. Thus, metabolic demands may be reached sooner on a human food diet, which in turn leads to improved foraging efficiency. In particular, a reduction in time spent feeding is associated with an increase in time spent resting. We investigated changes in time budget in a group of vervets (Chlorocebus aethiops pygerthrus) living in a tourist and cultivated area of Entebbe, Uganda (Zoo group). Saj collected 123 hr of focal observations on 17 individuals. Human food constituted half of the diet of Zoo group. Access to human food resulted in a high proportion of time resting and a low proportion of time feeding. The group had a small average daily range and a small home range in relation to other reports on unprovisioned groups. The time budget differences suggest that the juveniles spent more time moving and feeding and less time resting than adults did, and that adult females were more social than adult males were. These patterns have been observed in both provisioned and unprovisioned vervet groups. In contrast to a report from an unprovisioned group (Harrison, 1983), lactating females in this provisioned situation were able to maintain feeding and activity levels similar to those of other adults. However, adult females spent significantly less time consuming human food than juveniles did. We suggest that the risk associated with human food consumption may explain the low consumption of human food by females with dependent offspring. The differences may also reflect the different nutritional requirements of lactating females or the tendency for juveniles to be more exploratory than other group members.     

Diet and activity budget of <Emphasis Type="Italic">Rhinopithecus roxellana</Emphasis> in the Qinling Mountains,China

We collected data on diet and daytime activity budget, and investigated the phenology of food trees and food abundance for a group of Rhinopithecus roxellana on the East Ridge of Yuhuangmiao in the Qinling Mountains from November 2001 to December 2003. We calculated the seasonal activity budget using data collected by scan sampling from 84 full-day observations (winter 16, spring 18, summer 28, autumn 22 days). During scan sampling we recorded behavioral states, and the food items and species consumed. The subjects consumed 84 plant species, including trees and shrubs of 29 families, and lichens. Food species varied seasonally. The overall diet of R. roxellana consisted of 29.4% fruit/seeds, 29.0% lichens, 24.0% leaves, 11.1% bark, 4.2% buds, 1.3% twigs and 1.0% unidentified items. Because the abundance of different food items varied seasonally, the monkeys had to shift their major food items seasonally. The annual activity budget of R. roxellana was 36.2% time spent resting, 35.8% feeding, 22.9% moving, and 5.1% other behavior. Seasonal changes in activity budget were observed. R. roxellana spent more time moving in autumn, when the quality of the food might be highest, and least time moving in winter when the food quality might be lowest. Thus, this type of monkey has a passive foraging strategy.     

Time budget of the green monkey,Cercopithecus sabaeus: Some optimal strategies

Members of a single group of green monkeys spent, on average, 44.8% of their waking time foraging, 46.7% resting, and 8.5% in social activities, over 1 year. There was significant variation in activity budgets over months (ranging from 35 to 55% of the time spent feeding). Diurnal rhythms of feeding and ranging were influenced by the daily cycle of temperature in predictable ways in different seasons: in the dry season, activity was reduced if it was too hot or too cold, while the temperature in the wet season did not affect activities. Feeding was also synchronized among individuals on a finer time scale, irrespective of the time of day. There was closer synchrony when feeding on less common foods. An ecological model of foraging time and energetics was tested, using estimates of the costs and benefits of foraging and predicting how these are optimally balanced in relation to the food density. Both feeding time and distance traveled increased as food availability increased. Costs and benefits were balanced over several days. Comparisons between populations of Cercopithecus aethiopswere made; differences in time budgets were compared with differences in the availability and quality of food. Insufficient comparative data are available for firm conclusions about the role of different energetic and nutritive strategies in population differences.     

The effect of social and ecological factors on the time budget of wild vervet monkeys

Animals often have a limited time to perform different fitness‐enhancing activities, such as the trade‐off between socializing versus foraging in group‐living species. Many previous studies have focused on how ecological and social factors influence activity budget at the individual or group level in various species. However, few primate studies have focused on multiple study groups living within a similar habitat. Here, we analyse group, season and sex effects on the individual activity budget of wild vervet monkeys (Chlorocebus pygerythrus) living in four groups with overlapping home ranges. Generally, our findings support previous studies on primates. Our results indicate that intragroup competition may force larger groups to spend more time feeding and less time resting. We also found that seasonal variation, and therefore food availability, has a strong influence on the monkeys’ activity budget. Females, which are the philopatric sex in vervet monkeys, spent more time socializing while, in general, males spent more time resting. However, we did not find any difference on the time spent socializing between groups. Since there is evidence that not only time constraints and habitat quality but also group size influence individual behaviours and ultimately group living, we advise that future studies should focus on multiple groups of the same species living in the same habitat in order to better understand how all these variables are interlinked.     

Rhinopithecus bieti at Tacheng,Yunnan: Diet and Daytime Activities

We collected data on diet and activity budget in a group of Rhinopithecus bieti at Tacheng (99°18E, 27° 36'N, between 2,700–3,700 m asl), Yunnan, from March 1999 to December 2000. We mainly recorded species-parts eaten with feeding scores from scanning state behaviors of one-male units in tree-crowns. We also conducted microscopic analysis of feces collected monthly. The subjects consumed 59 plant species, belonging to 42 genera in 28 families, of which 90 species-parts were distributed as follows: 21 in Winter, 38 in spring, 39 in Summer, 47 in autumn. Conversely, the group annually spent, on average, 35% of daytime feeding, 33% resting, 15% moving, and 13% in social activities. Seasonal changes are apparent in daytime budget and food item-related feeding time in tree-crowns, food remains in feces, and the number of species-parts eaten. Correlations within and between food items and time budget clearly indicate maximization of foraging effectiveness and minimization of energy expenditure. In consideration of reports from northern and southern groups, that which underlay the specific adaptation to the habitat appeared to be similar to those of other colobines. Thus, the ultimate factors for survival of the species are more hopeful than expected.     

Time budget and activity patterns of the lion-tailed macaque (Macaca silenus)

We studied time budgeting of lion-tailed macaques in the Anamalai Wildlife Sanctuary, Tamil Nadu, India, with regard to seven activity categories. Groups spent >50% of their time feeding and foraging, 33% of the time resting, and 15% moving. More energetic activities were spread uniformly through the day. Feeding had two annual peaks: one closely following the northeast monsoon and the other corresponding to the southwest monsoon. These also coincided with peaks of food availability and mating. Time saved in feeding was spent mostly on resting. Ranging showed a pattern contrary to that of time spent moving and was related more to weather than to food availability; it increased during cooler periods. The middle and upper stories of the canopy were used >93% of the time. The ground was used rarely. Time budgeting characteristics of the lion-tailed macaque are primarily frugiinsectivorous adaptations to a wet evergreen forest habitat.     

Differences in Activity Budgets and Diet Between Semiprovisioned and Wild‐Feeding Groups of the Endangered Barbary Macaque (Macaca sylvanus) in the Central High Atlas Mountains,Morocco

The Barbary macaque, Macaca sylvanus is a very adaptable primate species occupying a wide range of habitats in Morocco and Algeria. Several groups of this endangered macaque can be found in tourist sites, where they are affected by the presence of visitors providing food to them. We compare the activity budgets and the diet of semiprovisioned and wild‐feeding groups of Barbary macaques in the central High Atlas Mountains of Morocco from February to August 2008. We used instantaneous scan sampling at 15‐min intervals. The behaviors included in the activity budget were feeding, moving, foraging, resting, and aggressive display. Food items were grouped into seven categories. We found no differences between the two groups in the daily percentages of records attributed to feeding. The semiprovisioned group spent significantly more time engaged in resting and aggressive behavior, and foraged and moved significantly less than the wild‐feeding group. There was no significant difference between the two groups in time spent eating leaves, fruits, or roots and bark. The semiprovisioned group, however, spent significantly less time per day feeding on herbs, seeds, and acorns than the wild‐feeding group. Human food accounted for 26% of the daily feeding records for the semiprovisioned group and 1% for the wild‐feeding group. Our findings agree with previous studies and indicate that in the tourist site, where food is highly clumped, macaques decreased foraging time yet showed higher levels of contest competition. Our results support the common claim that the diet of the Barbary macaque is highly flexible, differing among its varied habitats. Conservation efforts for the Barbary macaques should take into account the changes in behavior that human‐modified environments may cause.     

Behavior, Diet, and Movements of the Sulawesi Crested Black Macaque (Macaca nigra)

We present the first field study of activity budgets, diet and ranging patterns of the Sulawesi crested black macaque, Macaca nigra, one of seven macaque species endemic to Sulawesi, Indonesia. We studied three crested macaque groups, ranging in size from 50 to 97 individuals, for 18 months in the Tangkoko-DuaSudara Nature Reserve, North Sulawesi. They spent 59% of the day moving and procuring food, especially fruits, and 41% of the day resting and socializing. Their diet is composed of more than 145 species of fruit (66% of observed feeding bouts), vegetative material (2.5%), invertebrates (31.5%), and occasional vertebrate prey. Group differences were more pronounced than seasonal or diurnal differences. Specifically, the largest group moved farther during the day, moved at a faster and more uniform rate, ate less fruit, rested more, and socialized less than the smaller groups did. The largest group had the largest home range, but it included less primary forest and more disturbed habitat than the ranges of smaller groups. There are individual differences in activity budgets of adult males and females in time spent moving, resting, feeding, and socializing that may reflect differences in reproductive strategies of males versus females. The behavior of large juveniles is more similar to that of adults than to that of small juveniles. Daily movements and use of home range are correlated with diet. Macaques moved shorter distances as the proportion of time spent feeding on fruit increased, and the top four dietary items accounted for most of the variance in entry into hectare blocks of home range.     

Feeding ecology and foraging behaviour of impala Aepyceros melampus in Lake Mburo National Park, Uganda

Intersexual and seasonal variation in foraging behaviour of impala (Aepyceros melampus), was studied in the Lake Mburo National Park, Uganda. There was a moderate seasonal difference in foraging efficiency (as measured by ‘acceptable food abundance’), with a minimum in dry season and a maximum in Rainy season. The variation between sexes was more distinct with a pronounced minimum in time spent browsing of males in early wet season. By distinguishing between feeding time spent grazing and feeding time spent browsing the seasonal variation was confirmed. The proportion of foraging time spent feeding (expressed as ‘food ingestion rate’) showed an inverse pattern with a maximum in the late dry season (75.5%), decreasing values throughout the Rainy season and a minimum in early dry season (57.8%). Differences between sexes were explained in terms of reproductive demands and seasonal balance in terms of moderate climate throughout the year. Impala foraging patterns in the bimodal tropics (two Rainy seasons) is discussed and compared with unimodal tropics. The findings are matched against current ideas on optimal foraging.     

Seasonal Variation in the Activity Patterns and Time Budgets of <Emphasis Type="Italic">Trachypithecus francoisi</Emphasis> in the Nonggang Nature Reserve,China

Activity patterns and time budgets are 2 important aspects of animal behavior that researchers use to investigate ecological influences on individual behavior. We collected data on activity patterns and time budgets in 1 group of François’ langurs (Trachypithecus francoisi) from August 2003 to July 2004 in the Nonggang Nature Reserve, Guangxi Province, China, via instantaneous scan sampling method with 15-min intervals. The diurnal activity pattern of François’ langurs showed morning and afternoon feeding peaks, with a midday resting peak. Seasonal change was apparent in the activity pattern: 2 significant feeding peaks occurred in the dry season and only 1 significant feeding peak in the rainy season. The group spent an average of 51.5% of the daytime resting. Feeding and moving accounted on average for 23.1% and 17.3% of the activity budget, respectively. Subjects spent little time on social activities, averaging 2% for grooming and 5.5% for playing. Their time budgets showed significant seasonal variation: they spent a greater proportion of time on feeding and less time on resting and grooming in the dry season than in the rainy season. They also differed among different sex-age classes: immatures spent more time playing, whereas adults devoted more time to resting, feeding, and grooming. Correlations between time budgets and food items or food availability clearly indicated that François’ langurs might adopt an energy-maximizing strategy when preferred foods were scarce in the dry season.     

Habitat Quality and Activity Budgets of White-Headed Langurs in Fusui,China

Within a species, habitat quality may be a factor causing different activity budgets between populations. The habitat of white-headed langurs (Trachypithecus leucocephalus) has been seriously disturbed in Fusui Rare and Precious Animal Nature Reserve, China, where we carried out a study of their socioecology from September 1997 to September 1998. We collected data on langur activity budgets from the main population located in the central part of a group of limestone hills. We classified habitat quality into 4 grades according to the extent of human disturbance. We showed that the two main study groups of white-headed langurs spent on average 50% of time resting, 13% feeding, 18% moving (including foraging), 11% grooming, and 7% playing. Langur time budgets showed no significant seasonal change, but they differed among different sex-age classes. Infants and juveniles spent about 20.3% of time playing, whereas adults spent only 0.2% playing. The group in high quality habitat engaged less in feeding and more in playing than the group in low quality habitat did. Habitat quality influenced the playing time of young white-headed langurs and may be vital to their successful maturation.     

Behavioral activities and diet of Azaras’s capuchin monkey,Sapajus cay (Illiger, 1815), in a forest remnant of the Brazilian Cerrado

ABSTRACT

Azaras’s capuchin monkey (Sapajus cay) is a poorly studied species in ecological aspects. We investigated behavioral activities and diet of a group of S. cay in a remnant of the Brazilian Cerrado. We sought to identify the most frequent behavior that the group engaged in, as well as to verify possible differences in behavioral patterns and diet between adult males and females. From January to July 2012 we collected behavioral and foraging data for a group of 21 individuals using scan sampling. Behaviors and food items consumed were analyzed using percentages and two proportions Z-tests to assess differences between males and females. We obtained 878 scans in approximately 202 hours of sampling effort, resulting in 4,159 individual activity records of capuchin monkeys. The group allocated time to traveling (41.3%), resting (25.5%), feeding (14.3%), foraging (13.7%), and social activities (5.1%). Females spent more time foraging and feeding, while males spent more time resting. Fruits (61.4%), invertebrates (15.3%), and seeds (14.3%) were the most common food items consumed. We did not find differences in food consumption between sexes. Behavioral activities may be influenced by habitat quality of the studied area, opportunistic habits, and plasticity in the diet.     

Sleeping Cave Selection,Activity Pattern and Time Budget of White-Headed Langurs

We describe the activity patterns and time budgets of white-headed langurs that were confined to about 4 km² of Longlin habitat in Fusui County, Guangxi Province, China. Between February and December 1996, we observed 6 langur groups monthly via group focal sampling and continuously recording the behavior of a focal group. Our results indicate that the langur groups selected stone caves on cliffs as sleeping sites. The daily activity pattern outside caves had 8 stages: (1) leaving the cave in the early morning; (2) moving and resting; (3) morning feeding; (4) moving a long distance; (5) resting at noon; (6) afternoon feeding; (7) moving back to the cave, and (8) entering the cave. Over the year, langurs spent a daily average of about 11.5 h outside caves and about 12.5 h inside caves. Moving accounted for 7% (spring), 7% (summer-autumn) and 13% (winter) of the time budget, and langurs spent 9% (summer-autumn) and 14% (spring) to 20% (winter) of their time feeding. Resting accounted for 79% of the time budget in spring, 84% in summer-autumn, and 57% in winter. Sunbathing only occurred in winter and accounted for about 10% of the time budget. One-way ANOVA and multiple range tests demonstrated that time budgets differed significantly among seasons. Langurs spent significantly more time feeding and moving in winter than in spring and summer-autumn, but significantly less time resting in winter than in spring and summer-autumn.     

Seasonal patterns of diet and ranging in two species of tamarin monkeys: Stability versus variability

From June through December, data were collected on the diet and ranging patterns of moustached (Saguinus mystax) and saddle-back (Saguinus fuscicollis) tamarin monkeys in the Amazon Basin of northeastern Peru. During this 7-month period, insects and nonleguminous fruits accounted for 83% of tamarin feeding and foraging time. Despite marked seasonal variation in rainfall and forest productivity, patterns of habitat utilization, day range, dietary diversity, resource exploitation, and activity budget remained relatively stable throughout the year. Moustached and saddle-back tamarins appear to solve problems of food acquisition and exploit patchily distributed feeding sites using a relatively limited set of foraging patterns. In general, these primates concentrate their daily feeding efforts on several trees from a small number of target plant species. These feeding sites are uncommon, produce only a small amount of ripe fruit each day, and are characterized by a high degree of intraspecific fruiting and flowering synchrony. Trees of the same species are frequently visited in succession, and individual feeding sites are revisited several times over the course of 1–2 weeks. This type of foraging pattern occurred during both dry and wet seasons and when exploiting fruit, nectar, legume, and exudate resources. Seasonal variation in the percentage of feeding and foraging time devoted to insectivory was also limited. In this investigation, there was no consistent evidence that temporal changes in overall forest fruit production had a major impact on the feeding, foraging, or ranging behavior of either tamarin species.     

Diet and ranging behavior of the endangered Javan gibbon (Hylobates moloch) in a submontane tropical rainforest

Altitude influences forest structure and food abundance and distribution, which in turn affect primate feeding and ranging patterns. Javan gibbons (Hylobates moloch) are endemic to forests spanning a broad range of altitudes on Java, Indonesia. Most information about Javan gibbon behavior comes from studies in lowland forests, while the vast majority of wild gibbons remaining inhabit hill and lower montane forests. We studied the diets, activity patterns, and ranging behavior of three gibbon groups in hill/lower montane (950-1,100?m asl) forest in the Gunung Halimun-Salak National Park (GHSNP) from April 2008 to March 2009. The mean home range size was 37?ha and the mean daily path length was 1,180?m. The study groups spent 36% of time feeding, 41% resting, 15% traveling, 6% engaging in social behavior, and 2% in aggressive interactions. Fruit was the most important food (63% of feeding time) followed by leaves (24%), and flowers (12%). Our results suggest that Javan gibbons in higher elevation habitats have substantially larger home ranges than lowland populations, despite broad similarity in their activity budgets and diets. Conservation managers should consider the effects of altitude and habitat quality on gibbon ranging behavior when developing habitat corridors, selecting sites for translocation or reintroduction projects, and designating and managing protected areas.     

Rapid shifting of foraging pattern by Yakushima macaques ( Macaca fuscata yakui ) in response to heavy fruiting of Myrica rubra

We describe short-term changes in foraging behavior by wild Yakushima macaques (Macaca fuscata yakui),which inhabit a warm-temperate broad—leaved forest on Yakushima Island (30°N, 131°E), Japan. Rapid changes of dietary composition, activity budget, and range use by the monkeys occurred from May to June, apparently associated with changes in the availability of the fruit of Myrica rubraBefore the fruit ripened, monkeys spent less time moving and more time feeding on many species of leaves, which accounted for 40% of feeding time. However, when M. rubrabegan to ripen, they fed intensively on the fruit, which accounted for three-fourths of feeding time,though the activity budget remained unaffected As fiuit of M. rubradecreased,the monkeys fed more on the fruit of other species and on insects, and spent more time moving at higher speeds. There marked shifts in foraging pattern occurred within only two months. In terms of moving cost and dietary quality,Yakushima macaques shifted their foraging pattern according to the availability of M. rubrafrom a “low-cost, low-yield” strategy to a “low-cost, high-yield” strategy, and then to a more costly strategy. The ability to make such rapid shifts in foraging pattern may allow the macaques to effectively use the highly variable food supply within their small range.     

Effect of habitat quality on the ecological behaviour of a temperate-living primate: time-budget adjustments

Barbary macaques, like other non-human primates living in highly seasonal temperate environments, display high monthly variations in their diet. In addition, their diet changes according to the habitat type they colonize and to the degree of habitat degradation due to resource exploitation by local people, in particular through pastoralism. We studied the time-budget adjustments of wild Barbary macaques in three cedar–oak forests impacted by different intensities of grazing pressure from goats and sheep. We examined how diet variations influenced the time monkeys spent in their activities and their day range lengths (i.e. their energy costs). At three studied sites, diet composition and time budgets showed marked seasonal variations. Diet composition had a strong influence on monkeys’ time budget. In the forest where pastoralism was the highest, diet included a greater proportion of underground resources, shrub fruit and acorns, which led to an increase in the time spent foraging and moving, as well as an important increase in day range lengths. Energy costs were therefore higher in a degraded environment than in a suitable habitat. The monkeys living in forests subjected to pastoralism took advantage of increased day lengths to spend more time searching for food. However, in the forest with the highest pastoralism pressure, although monkeys spent more time foraging, they spent less time feeding than monkeys at the other sites. In addition, they appeared to have reached the limits of the available time they could devote to these activities, as their diurnal resting time was at its lowest level over several months. Temperature variations did not appear to modify monkeys’ time budgets. In the least favourable habitat, saving time from resting activity allowed monkeys to maintain a relatively high level of social activity, partly linked to rearing constraints.     

Environmental influences on mountain gorilla time budgets

Data on the time budgets of mountain gorillas (Gorilla gorilla beringei) were collected during field studies in the Virunga Volcanoes region of Rwanda and Zaire. Focal sampling was used to determine the proportion of time that individuals of different age/sex classes spent in several mutually exclusive activity states. The gorillas spent the majority of daylight hours feeding; most of the rest of the day was devoted to resting, with little time spent moving or engaged in social activity. The time budget varied among the different subhabitats used by the gorillas, and the gorillas satisfied subsistence needs more quickly when in areas where food was more abundant and/or of better nutritional quality. Silverbacks spent more time feeding than all other age/sex classes, but age/sex class differences were not great. All age/sex classes responded to variability in habitat quality in similar fashion. Unlike the case for many other primates, there was no significant seasonal variation in time budgets. There was a direct relationship between group size and time spent feeding, although variation in relation to group size was lower than that in relation to variation in habitat quality. These results are consistent with the relationship of feeding time to body size in primates. They are also consistent, with other evidence that social foraging entails a cost to gorilla females, but that this cost is low in comparison to those faced by many other primates. Permanent association with males apparently offers little ecological disadvantage to females, who are likely to be more than compensated by mutualistic benefits.     

Influence of climatic variables, forest type, and condition on activity patterns of Geoffroyi's spider monkeys throughout Mesoamerica

Understanding how species cope with variations in climatic conditions, forest types and habitat amount is a fundamental challenge for ecologists and conservation biologists. We used data from 18 communities of Mesoamerican spider monkeys (Ateles geoffroyi) throughout their range to determine whether their activity patterns are affected by climatic variables (temperature and rainfall), forest types (seasonal and nonseasonal forests), and forest condition (continuous and fragmented). Data were derived from 15 published and unpublished studies carried out in four countries (Mexico, El Salvador, Costa Rica, and Panama), cumulatively representing more than 18 years (221 months, >3,645 hr) of behavioral observations. Overall, A. geoffroyi spent most of their time feeding (38.4 ± 14.0%, mean ± SD) and resting (36.6 ± 12.8%) and less time traveling (19.8 ± 11.3%). Resting and feeding were mainly affected by rainfall: resting time increased with decreasing rainfall, whereas feeding time increased with rainfall. Traveling time was negatively related to both rainfall and maximum temperature. In addition, both resting and traveling time were higher in seasonal forests (tropical dry forest and tropical moist forest) than in nonseasonal forests (tropical wet forest), but feeding time followed the opposite pattern. Furthermore, spider monkeys spent more time feeding and less time resting (i.e., higher feeding effort) in forest fragments than in continuous forest. These findings suggest that global climate changes and habitat deforestation and fragmentation in Mesoamerica will threaten the survival of spider monkeys and reduce the distributional range of the species in the coming decades. Am. J. Primatol. 73:1189–1198, 2011. © 2011 Wiley Periodicals, Inc.     

Interpopulation differences in activity patterns ofMacaca sylvanus in the Moroccan Middle Atlas

We studiedMacaca sylvanus populations from a) a protected, relatively undamaged climax Cedar forest and b) a degraded, mixed Cedar-Oak forest. Animals exhibit considerable differences in demographic, social and time budget characteristics. In the degraded forest there were fewer social groups of smaller average group size and lower population density. Differences in habitat quality, patchiness and intensity of human activities between the two localities are reflected in macaque activity patterns. In the degraded forest the animals allocate less time to feeding, foraging (clumped food resources, smaller group sizes) and Vigilance (more habituated to human presence). They allocate more time to resting and they are involved more frequently in grooming (probably an indication of social tension within groups). In contrary social structures and wild stock, population is declining.