Population Of Long-tailed Macaques Research Articles

Changes in Activity Patterns and Intergroup Relationships After a Significant Mortality Event in Commensal Long-Tailed Macaques (Macaca Fascicularis) in Bali, Indonesia

Little is known regarding behavioral and social responses of free-ranging primates to demographic changes emerging from significant mortality events. Here, we report on the activity patterns and intergroup sociospatial relationships in a commensal population of long-tailed macaques (Macaca fascicularis) in Bali, Indonesia, that underwent a significant mortality event in summer 2012. During the period of interest, we noted heightened mortality in three of the five social groups present in this population, with adult females and juveniles experiencing higher mortality rates than adult and subadult males. Limited diagnostic data regarding pathogen identification and a lack of any conclusive etiology of the deaths prevent our ascertainment of the agent(s) responsible for the observed mortality, but given the characteristics of the event we assume it was caused by a transmissible disease outbreak. Comparing the pre- and post-mortality event periods, we found significant differences in activity patterns, including a decreased proportion of affiliation in adult females. This result is likely indicative of enhanced social instability induced by the high mortality of adult females that constitute the stable core of macaque social structure. A higher social tension between groups after the mortality event was indicated by more frequent and intense agonistic intergroup encounters. Intergroup conflict success was inversely proportional to the rate of mortality a group suffered. Our results illustrate how changes in demographic structure caused by significant mortality events may have substantial consequences on behavior and social dynamics in primate groups and at the level of a population.

Genetic diversity and population structure of long-tailed macaque (Macaca fascicularis) populations in Peninsular Malaysia

The genetic diversity and structure of long-tailed macaques (Macaca fascicularis) in Peninsular Malaysia, a widely used non-human primate species in biomedical research, have not been thoroughly characterized. Thirteen sites of wild populations of long-tailed macaques representing six states were sampled and analyzed with 18 STR markers. The Sunggala and Penang Island populations showed the highest genetic diversity estimates, while the Jerejak Island population was the most genetically discrete due to isolation from the mainland shelf. Concordant with pairwise F(st) estimates, STRUCTURE analyses of the seven PCA-correlated clusters revealed low to moderate differentiation among the sampling sites. No association between geographic and genetic distances exists, suggesting that the study sites, including island study sites, are genetically if not geographically contiguous. The status of the genetic structure and composition of long-tailed macaque populations require further scrutiny to develop this species as an important animal model in biomedical research.

Studi Populasi Monyet Ekor Panjang (Macaca Fascicularis) Di Pulau Condong Darat Desa Rangai Kecamatan Ketibung Kabupaten Lampung Selatan

The Condong Terestrial Island is one of the island belong to tourist area, Pasir Putih, in Rangai village. bThis island has a natural vegetation and become conservation area for all living things.One of them is the long tailed macaques (Macaca fascicularis),or the crab-eathing macaques.The objective of this research is to know about the number and the population density of long tailed macaques (Macaca fascicularis) at Condong Terestrial Island. The research has been done fromJanuary 16thto February 5th 2012. This research was using concentrated method. Data was collected by visiting the existence of long tailed macaques. Population of longtailed macaques was calkulated by noting the time and the number of individuals admitted at any point of observation, the number of crab-eating macaques in and out at any poin wast recorded on tally sheets to avoid repetition of the calculation. The observation was conducted during the daytime started from 6am to 6pm. The result of this research shown that the total number of this long tailed macaques is about 140 individu with population density is about 28 ekor per hectare. Key words : Condong Island, Macaca fascicularis, population density, population study

Condition and population size of Macaca fascicularis (long-tailed macaque)

This study discusses the population size of Macaca fascicularis in Penang Botanical Gardens, Malaysia. The scan sampling method was used to observe the groups of M. fascicularis in the gardens. The study was carried out from February 2007 to June 2007. Chi-square test was used to find the correlation of individual appears on the specific area of the gardens. The total number of observations that were carried out during this study was 1134. Among these observation the adult females were observed as 22% (P = 0.15), adult males 17% (P < 0.05), juveniles 56% (P < 0.05) and infants 5% (P = 0.34). This study revealed that the population of long tailed macaques is decreasing in Penang Botanical Gardens. In arranging to get better human contact with macaque and at the similar time to keep up a developed macaque inhabitants in Botanical Gardens Penang, there is an imperative requirement for wildlife department to enhance their safety, food availability and predator’s threats. Key words: Macaca fascicularis, scan sampling, botanical gardens Penang, wild life.

Radiographic measurement of the cardiothoracic ratio in a feral population of long-tailed macaques ( Macaca fascicularis)

The cardiothoracic ratio is often used as a proxy measure of cardiovascular pathophysiology in humans but less frequently in nonhuman primates, for whom little published data are available to establish normal values. The present study is the first to examine relative cardiac size in a feral population of primates. This report presents estimates of the cardiothoracic ratio in long-tailed macaques ( Macaca fascicularis) from Bali, Indonesia. The mean cardiothoracic ratio for the study sample was 0.55, above the commonly used threshold of 0.50 for identifying an enlarged heart in human medicine. Future research on wild populations of macaques is needed and should include multiple assessments of cardiac function including both radiography and echocardiography.

Assessing Natural Introgression in 2 Biomedical Model Species, the Rhesus Macaque (Macaca mulatta) and the Long-Tailed Macaque (Macaca fascicularis)

Rhesus macaque (Macaca mulatta) and long-tailed macaque (Macaca fascicularis) are the 2 most commonly used primate model species in biomedical sciences. Although morphological studies have revealed a weak hybridization at the interspecific contact zone, in the north of Indochina, a molecular study has suggested an ancient introgression from rhesus to long-tailed macaque into the Indo-Chinese peninsula. However, the gene flow between these 2 taxa has never been quantified using genetic data and theoretical models. In this study, we have examined genetic variation within and between the parapatric Chinese rhesus macaque and Indo-Chinese long-tailed macaque populations, using 13 autosomal, 5 sex-linked microsatellite loci and mitochondrial DNA sequence data. From these data, we assessed genetic structure and estimated gene flow using a Bayesian clustering approach and the "Isolation with Migration" model. Our results reveal a weak interspecific genetic differentiation at both autosomal and sex-linked loci, suggesting large population sizes and/or gene flow between populations. According to the Bayesian clustering, Chinese rhesus macaque is a highly homogeneous gene pool that contributes strongly to the current Indo-Chinese long-tailed macaque genetic makeup, whether or not current admixture is assumed. Coalescent simulations, which integrated the characteristics of the loci, pointed out 1) a higher effective population size in rhesus macaque, 2) no mitochondrial gene flow, and 3) unilateral and male-mediated nuclear gene flow of approximately 10 migrants per generation from rhesus to long-tailed macaque. These patterns of genetic structure and gene flow suggest extensive ancient introgression from Chinese rhesus macaque into the Indo-Chinese long-tailed macaque population.

Hybridization and Stratification of Nuclear Genetic Variation in Macaca mulatta and M. fascicularis

Genotypes for 13 short tandem repeats (STRs) were used to assess the genetic diversity within and differentiation among populations of rhesus macaques (Macaca mulatta) from mainland Asia and long-tailed macaques (M. fascicularis) from mainland and insular Southeast Asia. These animals were either recently captured in the wild or derived from wild-caught founders maintained in captivity for biomedical research.A large number of alleles is shared between the two macaque species but a significant genetic division between them persists. This distinction is more clear-cut among populations that are not, or are unlikely to have recently been, geographically contiguous. Our results suggest there has been significant interspecies nuclear gene flow between rhesus macaques and long-tailed macaques on the mainland. Comparisons of mainland and island populations of long-tailed macaques reflect marked genetic subdivisions due to barriers to migration. Geographic isolation has restricted gene flow, allowing island populations to become subdivided and genetically differentiated. Indonesian long-tailed macaques show evidence of long-term separation and genetic isolation from the mainland populations, while long-tailed macaques from the Philippines and Mauritius both display evidence of founder effects and subsequent isolation, with the impact from genetic drift being more profound in the latter.

Morphological and Body Color Variation in Thai Macaca fascicularis fascicularis North and South of the Isthmus of Kra

Long-tailed macaques (Macaca fascicularis fascicularis) are widely distributed in Southeast Asia and are morphologically and genetically (Tosi et al. in International Journal of Primatology 23:161–178, 2002) distinguishable on either side of the Isthmus of Kra (ca. 10.5°N). We compared the somatometry and body color of 15 local populations of long-tailed macaques in Thailand distributed over areas from 6.5°N to 16.3°N and also a Thai rhesus macaque population at 17.2°N. Limb proportions and body color variation follow the geographical trend. However, contrary to a previous report, body size does not decrease with latitude in the northern group and also in the southern (southerly distributed) rhesus macaque. Relative tail length (RTL) and color contrast in yellow between the back and thigh are the sole traits that distinctively separate the 2 groups: the southern group has a long relative tail length (RTL >125%) and small color contrast, whereas the northern group has a short RTL (<120%) and large color contrast. The southern rhesus macaques appear to have somatometric and body color traits that follow the geographical trend in long-tailed macaques, though they maintain their distinctive species-specific traits of shorter RTL (ca. 55%), shorter relative facial length, and a bipartite body color pattern. Researchers assume that the northern group of long-tailed macaques and the southern rhesus macaques had undergone partial introgression with each other. Montane refugia present during the glacial period are localities in which introgression occurred in long-tailed macaques.

Morphology and somatometric growth of long-tailed macaques (Macaca fascicularis fascicularis) in Singapore

Crab-eating, or long-tailed, macaques [Macaca fascicularis (Raffles, 1821)] have been studied extensively throughout their distribution in South and South-east Asia. Despite this extensive body of research, the island population of long-tailed macaques from Singapore remains virtually undescribed. In the present study, we compare the morphometric variability and patterns of growth observed in a population sample from Singapore with a composite sample from Thailand, north of the Isthmus of Kra. The results of our analyses indicate that there are statistically significant differences between the two populations in adult size and shape. For both males and females, the Singapore population is smaller than the Thai population. Relative to body length, the Singapore macaques exhibit significantly longer tails, and, relative to cranial length, they exhibit significantly more narrow faces than the Thai macaques. Although levels of sexual dimorphism for most morphometric traits are very similar, indicating similar levels of male–male competition for females, the Singapore males exhibit a significantly larger testicular volume relative to body weight, suggestive of an alternative male reproductive strategy. In addition to adult somatometric size and shape, comparisons of growth patterns relative to age and body size reveal significant differences between the two population samples. Combined, these results suggest either that statistically significant differences in adult morphology and patterns of growth can occur in presumably reproductively cohesive subspecies, or the Singapore macaques may be taxonomically distinct. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 92, 675–694.

Temple and pet primates in Thailand

In Thailand, a predominantly Buddhist country, isolated populations of long-tailed macaques (Macaca fascicularis) especially may be found at temples in both rural and urban areas where they are provisioned by people making merit although the monkeys may be shot as agricultural pests in adjacent rice or corn fields in rural areas. At the same time, macaques and gibbons, especially the lar gibbon (Hylobates lar), have been kept as pets in both rural and urban areas. Gibbons even are reported to be the « favorite pet for Thais ». The number of primates being offered for sale has risen dramatically as legal and illegal timbering have reduced Thailand’s forest cover to perhaps no more than 12 %, peripherali-zing primate populations and making them more vulnerable to hunting. A provision in Thai law permitted individuals to possess as many as two primates or other wild animals of the same species — « a potential pair to promote breeding » — even though their capture and sale was prohibited. Changes in Thailand’s wildlife laws governing private possession of wild animals have caused owners to abandon pets to government agencies and temples. Private rescue centers offer acute care and permanent shelter for some of these primates but cannot cope with the numbers involved. Pilot studies suggest that rehabilitation and réintroduction may be feasible alternatives for some former captive gibbons.

Male migration and rank acquisition in wild long-tailed macaques ( Macaca fascicularis)

In a 3-year study of a wild population of long-tailed macaques ( Macaca fascicularis), 52 male migrations from and into six study groups were observed. Two hypotheses derived from the literature were confirmed: (1) younger males immigrate more often into adjacent groups than older males, who immigrate more often into groups further away; and (2) younger males migrate more often together with group-mates than older males do. Two types of immigrants were distinguished: ‘unobtrusive’ and ‘bluff’. The unobtrusive immigrants entered low in the male dominance hierarchy and were males of all age classes, whereas the bluff immigrants attempted to take over the highest dominance rank of their new group and were all young adult males. Take-overs of dominance were also attempted by resident young males who had just reached full adulthood during a period of semi-solitariness. They behaved in a way similar to the bluff immigrants but were more successful than the bluff immigrants, who only succeeded in taking over small groups. The results indicate that knowing the other resident males might be the most important determinant of take-over success in multi-male groups.

Evolutionary Effect of the Absence of Felids on the Social Organization of the Macaques on the Island of Simeulue (Macaca fascicularis fusca, Miller 1903)

If the claim that predation risk is the main factor favouring group living in diurnal non-human primates is correct, a reduction in the risk of predation should lead to: (1) a reduction in the size of a primate group and of the parties into which it fissions, (2) a change in the relationship between the size of a party and its composition, and (3) (in South-East Asia) to a change in the relationship between party size and height in the canopy, for small parties. These predictions were tested in a comparison between a population of long-tailed macaques (Macaca fascicularis) in a Sumatran site where a variety of felids occurs, and one on the island of Simeulue, where no cats occur. The first two predictions were strongly supported, whereas the third was weakly supported by the data. The Simeulue monkeys were also different in morphology (blackish coats, reduced sexual dimorphism), lived at high densities in small home ranges, and were territorial. All these differences between the populations could be plausibly ascribed to the difference in predation risk from felids. It is concluded that the presence of felids has a profound influence on the social organization of this arboreal primate species.