Effect of Group Size on Time Budgets and Ranging Behavior of White-Headed Langurs in Limestone Forest, Southwest China

Nubian ibex (Capra nubiana) prefer steep terrain in their landscape to reduce risks of predation and human nuisance disturbances. They also use vigilance and time allocation to manage risk of predation. We studied time budgets and habitat selection of Nubian ibex to: (1) identify the habitat variables to which Nubian ibex were behaviorally responsive; (2) investigate how time budget responses of Nubian ibex were related to season, slope condition, group size, and sex-age structure; and (3) develop behavioral-based models that account for the variations in the behaviors of Nubian ibex across the landscape and seasons.To quantify time budgets, we took regular field observations on focal individuals of Nubian ibex classified according to their habitat, group size, sex, and age. For each focal observation, we quantified environmental variables that were thought to influence the behavioral responses of ibex. Then, we developed behavioral models by correlating the proportion of behaviors measured in focal animal observations to the influential environmental variables. The behaviors of Nubian ibex significantly varied with sex and age structure, season, habitat type, and slope conditions. Adult females are more vigilant than adult male ibex, especially in the spring. This correlates with breeding and nursing activities. Based on the characteristics of the habitat, ibex behave to minimize risks of predation and human nuisance disturbances while maximizing their food intake.

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Time budgets and synchrony of activities in muskoxen: the influence of sex, age, and season

Canadian Journal of Zoology ◽

10.1139/z97-789 ◽

1997 ◽

Vol 75 (10) ◽

pp. 1628-1635 ◽

Cited By ~ 43

Author(s):

Steeve D. Côté ◽

James A. Schaefer ◽

François Messier

Keyword(s):

Group Size ◽

Time Budget ◽

High Arctic ◽

Late Winter ◽

Time Budgets ◽

Adult Males ◽

Ovibos Moschatus ◽

Group Type ◽

June July ◽

Victoria Island

Synchrony of activities and time budgets of age–sex classes of muskoxen (Ovibos moschatus) was studied on Victoria Island in the Canadian High Arctic during late winter (April – late May), spring (late May – early June) and summer (mid-June – July). As revealed by the kappa (κ) coefficient of agreement, herd members exhibited significant synchrony in 79 of 82 groups. The degree of synchrony was not related to group size in mixed herds but decreased with group size in bachelor herds. Diversity in age–sex classes, group type (mixed versus bachelor), and season did not affect synchrony. However, synchrony was less among adult males than among other age–sex classes. Muskoxen were more synchronised at the start of activity bouts than at the end. As revealed by principal components analysis, calves tended to spend more time lying and standing and less time feeding than other age–sex classes. In addition, males in bachelor groups tended to feed more and rest less than males in mixed herds. Duration of active and lying bouts was not affected by age–sex class. Length of active bouts did not change with season, but lying bouts decreased in length significantly from late winter to spring and from spring to summer. We suggest that synchrony of activities maintains group cohesion but constrains the time budget of some group members, especially adult males.

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The Influence of Group Size On Predator Scanning and Foraging Behaviour of Wedgecapped Capuchin Monkeys (Cebus Olivaceus)

Behaviour ◽

10.1163/156853986x00982 ◽

1986 ◽

Vol 98 (1-4) ◽

pp. 240-258 ◽

Cited By ~ 74

Author(s):

Jan R. De Ruiter

Keyword(s):

Group Size ◽

Foraging Behaviour ◽

Group Formation ◽

Food Competition ◽

Food Sources ◽

Capuchin Monkeys ◽

Time Budgets ◽

Large Group ◽

Cebus Olivaceus ◽

Travel Distances

AbstractThe behaviour of two groups of wedgecapped capuchin monkeys, Cebus olivaceus, a small one (n = 8) and a large one (n = 25) was recorded. Time budgets and other aspects of behaviour depended on group size. The differences can be explained as: adjustment to predation risk and intra-group food competition. In order to evade predation, members of the small groups scan more and stay at greater heights than those of the large group. Higher food competition within the large group was reflected in the composition of its diet, in longer travel distances, and higher levels of social behaviour. In particular during the dry season, the large group exploited unattractive and risky food sources. These results support ALEXANDER'S hypothesis on the causes of group formation.

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Effect of habitat fragmentation on ranging behavior of white-headed langurs in limestone forests in Southwest China

Primates ◽

10.1007/s10329-017-0600-4 ◽

2017 ◽

Vol 58 (3) ◽

pp. 423-434 ◽

Cited By ~ 5

Author(s):

Zhonghao Huang ◽

Peisong Yuan ◽

Henglian Huang ◽

Xiaoping Tang ◽

Weijian Xu ◽

...

Keyword(s):

Habitat Fragmentation ◽

Southwest China ◽

Ranging Behavior

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Diet, food availability and climatic factor drive ranging behavior of white-headed langurs in the limestone forest of Guangxi, southwest China

动物学研究 ◽

10.24272/j.issn.2095-8137.2020.292 ◽

2021 ◽

Vol 0 (0) ◽

pp. 0-0

Author(s):

kechu Zhang ◽

◽

Qihai Zhou ◽

Huailiang Xu ◽

Zhonghao Huang ◽

...

Keyword(s):

Food Availability ◽

Southwest China ◽

Climatic Factor ◽

Ranging Behavior

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VIGILANCE IN BRONZE MANNIKIN GROUPS: THE CONTRIBUTIONS OF PREDATION RISK AND INTRA-GROUP COMPETITION

Behaviour ◽

10.1163/156853900502213 ◽

2000 ◽

Vol 137 (5) ◽

pp. 565-578 ◽

Cited By ~ 22

Author(s):

Nicola Coumi ◽

Rob Slotow

Keyword(s):

Predation Risk ◽

Group Size ◽

Foraging Behaviour ◽

Random Numbers ◽

Time Budgets ◽

Group Competition ◽

Measured Time ◽

The Mean

AbstractWe describe foraging behaviour and time budgets of the gregarious bronze mannikin, Lonchura cucullata. In addition to being the first such study of a southern African granivore, this was the first study of a group-forager to differentiate between vigilance for other flock members (conspecifics) and vigilance for predators. We verified a perception of predation risk by placing five feeders at increasing distances from cover. The mean number of birds at a feeder decreased significantly with increasing distance from cover. We manipulated levels of aggression by restricting access to random numbers of feeding holes at various distances. The treatments succeeded in forcing birds to feed further from cover, and by inference, increased levels of aggression. We measured time budgets with focal samples on marked individuals. There was no influence of group size on time budgets. There was a non-significant (p < 0.06) trend for vigilance to increase with increasing distance from cover (predation risk). There was no pattern in the relative vigilance for predators as opposed to vigilance for other flock members (conspecifics), either with group size, distance from cover, or manipulated levels of aggression. Despite our inability to detect patterns of vigilance for other flock members, we emphasize the importance of studies to elucidate such a process.

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