九寨沟自然保护区川金丝猴的分布及种群数量

2014年2月至5月,对四川省九寨沟自然保护区野生川金丝猴的种群分布、数量及其社会结构进行调查,初步探讨该种群与其他种群在外部形态和社会结构方面的差异性。采用"V"型路线法调查,发现九寨沟保护区共有川金丝猴4群。然后结合长时间的持续跟踪观察,证实家庭单元19个,全雄群3个,能区分不同个体296只。OMU大小平均为12.7只,其中OMU内的成年个体占38%,青少年个体占53%,幼仔占9%。成年与青少年比例为1∶1.39,成年雌雄的比例为3.84∶1。与秦岭种群的外部形态相比,该种群的成年雄性更为壮大,毛发弯曲程度明显;成年雌性毛发略显灰黑色,金黄色暗淡,大部分个体嘴角长有很小的肉瘤;青少年个体毛色泛白。亦发现九寨沟种群倾向于选择海拔偏高(2400—3550 m)的针叶林带活动。     

Inter-individual relationships in proboscis monkeys: a preliminary comparison with other non-human primates

This is the first report on inter-individual relationships within a one-male group of proboscis monkeys (Nasalis larvatus) based on detailed identification of individuals. From May 2005 to 2006, focal and ad libitum data of agonistic and grooming behaviour were collected in a forest along the Menanggul River, Sabah, Malaysia. During the study period, we collected over 1,968 h of focal data on the adult male and 1,539 h of focal data on the six females. Their social interactions, including agonistic and grooming behaviour, appeared to follow typical patterns reported for other colobines: the incidence of social interaction within groups is low. Of 39 agonistic events, 26 were displacement from sleeping places along the river, 6 were the α male threatening other monkeys to mediate quarrels between females and between females and juveniles, and 7 were displacement from feeding places. Although the agonistic behaviour matrix based on the 33 intra-group agonistic events (excluding events between adults and juveniles and between adults and infants) was indicative of non-significant linearity, there were some specific dominated individuals within the group of proboscis monkeys. Nonetheless, grooming behaviour among adult females within a group were not affected by the dominance hierarchy. This study also conducted initial comparisons of grooming patterns among proboscis monkeys and other primate species. On the basis of comparison of their grooming networks, similar grooming patterns among both-sex-disperse and male-philopatric/female-disperse species were detected. Because adult females in these species migrate to groups repeatedly, it may be difficult to establish the firm grooming exchange relationship for particular individuals within groups, unlike in female-philopatric/male-disperse species. However, grooming distribution patterns within groups among primate species were difficult to explain solely on the basis of their dispersal patterns. Newly immigrated females in some species including proboscis monkeys are eager to have social interactions with senior group members to improve their social position.     

Social Behavior,Reproductive Strategies,and Population Genetic Structure of <Emphasis Type="Italic">Lagothrix poeppigii</Emphasis>

For species of primates in which females emigrate, we would expect males within groups to be related to one another. Kin selection theory suggests that these males should associate preferentially with one another, be more affiliative and cooperative with one another than females are, and compete less overtly with one another over reproductive opportunities than males in female philopatric taxa do. Precisely these patterns of social behavior characterize well-studied populations of 2 of the 3 atelin primate genera: spider monkeys (Ateles) and muriquis (Brachyteles). For the third atelin genus, Lagothrix, patterns of intragroup social behavior have been less well-documented. We studied the social and reproductive behavior of lowland woolly monkeys (Lagothrix lagotricha poeppigii) in Ecuador during a one-year observational study and subsequently used molecular techniques to investigate population genetic structure and dispersal patterns for this taxon. Among adult male woolly monkeys, both affiliative and agonistic interactions were rare, and males were seldom in close proximity to one another. Relationships among male woolly monkeys are best characterized as tolerant, especially in the context of mating wherein direct competition among males was minimal despite the fact that females mated with multiple males. Relationships among females were likewise generally tolerant but nonaffiliative, though females often directed harassment towards copulating pairs. Affiliative interactions that did occur among woolly monkeys tended to be directed either between the sexes—primarily from female to male—or from younger towards older males, and the proximity partners of females tended to be members of the opposite sex. These results suggest that bonds between the sexes may be more important than same-sex social relationships and that direct female-female competition is an important feature of woolly monkey reproductive biology. Our genetic results indicate that, as in other atelins, dispersal by females is common, but some male dispersal likely occurs as well. In some but not all groups we studied, nonjuvenile males within social groups were more closely related to one another on average than females were, which is consistent with greater male than female philopatry. However, differences in these patterns among our study groups may reflect local variation in dispersal behavior.     

Habitat fragmentation and population size of the black and gold howler monkey (Alouatta caraya) in a semideciduous forest in Northern Argentina

A population of black and gold howler monkeys (Alouatta caraya) living near the southern limit of its distribution in a semideciduous forest located in northern Argentina was studied in 2003 to evaluate the possible effects of habitat fragmentation - owing to logging - on its density and social organization within it. Aerial photographs taken in 1982, 1992, and 2001 were used to compare maps of vegetation. These maps were used to evaluate changes in the area covered by forest fragments. From March to June 2003, 10-day monthly surveys of howlers were made in each fragment. A total of 232 individual howlers were counted, belonging to 34 groups plus a solitary adult female. Groups ranged from 2 to 19 individuals (mean = 6.82, SD = 4.23), and 21% of the groups contained more than one adult male. Adults accounted for 55% of the individuals, immatures for 45%, and infants represented 13% of the total. Data obtained were compared with information available for the same population for 1982 and 1995. Results revealed no significant changes in the area of fragments, the crude and ecological density of howlers, and group composition. Group sizes and group composition of howlers suggest that the population remained stable over the past 22 years. The density, number of groups, and individuals appears not to be affected by fragmentation and logging, but crude density was low compared with other less-disturbed habitats. The status of the population remains uncertain owing to isolation, and because there are no protected areas to ensure its stability for the future.     

Characteristics of a group of Hubei Golden Snub‐nosed Monkeys (Rhinopithecus roxellana hubeiensis) before and after major snow storms

Natural disasters can negatively affect primate population demography and social group structure. A clear understanding of these effects has important implications for wildlife conservation. The worst snow storms in nearly five decades hit portions of southern and central China between January 10 and February 6, 2008, presenting a unique opportunity to observe their immediate effects on a previously studied group of Hubei Golden Snub‐nosed Monkeys (Rhinopithecus roxellana hubeiensis) in temperate forests in Shennongjia Nature Reserve, Hubei Province, China. We recorded social and demographic characteristics of the group before and after the snow storms. The average group size decreased from 270 individuals before the storms to 197 individuals after the storms, a reduction of 27.2%. Adult females (30.1%), juveniles (38.1%) and infants (55.4%) suffered higher mortality than did adult males (15.7%). Despite age and sex‐based differences in mortality, the ratios of adult males to adult females, adults to immatures and adult females to immatures remained similar before and after the storms. However, higher mortality among females, juveniles and infants may reduce the group's long‐term potential for growth. Am. J. Primatol. 71:523–526, 2009. © 2009 Wiley‐Liss, Inc.     

Population Survey and Demographic Features of a Coastal Island Population of <Emphasis Type="Italic">Alouatta clamitans</Emphasis> in Atlantic Forest,Southeastern Brazil

Brown howlers (Alouatta clamitans) are endemic to the Atlantic Forest. Because only 7.5% of this fragmented forest remains in Brazil, there is an urgent need for studies of its ecology. Understanding island populations, still poorly researched in the relatively well-studied Alouatta, can provide important information for understanding habitat fragmentation and conservation. We studied brown howlers on the northern portion of the coastal and protected island, Ilha do Cardoso State Park. We used distance sampling methods on 5 transects to estimate population density of the howlers. Estimated howler density on the island is 10.6 individuals/km², with a total of 36 (21–62) individuals in a 3.4 km² area. The density is low, but similar to that of other large and preserved areas. By triangulating on vocalization and following groups, we estimate that there are 10 groups with an average of 4.5 individuals per group. Groups comprise 42% adult females, 27% adult males, 20% juveniles, 7% infants, and the remaining 4% subadult males. Howlers apparently use all appropriate habitats, including Atlantic Forest of plains and slopes. We believe that the howler population is maintaining a typical replacement on the island, with low birth rates and high survival rates, but long-term studies are required to test this. Small group size and associated social structure may be due to the particular environmental conditions on Ilha do Cardoso State Park.     

Female transfer between one-male groups of proboscis monkey (<Emphasis Type="Italic">Nasalis larvatus</Emphasis>)

Successful or unsuccessful female transfers were observed seven times during a 32-month field study of proboscis monkeys (Nasalis larvatus) inhabiting a riverine forest along a tributary of the Kinabatangan River, Sabah, Malaysia. In all cases, the females voluntarily left their own groups and immediately joined with another one. When adult females tried to shift to other groups, adult males called them back to their own groups, but appeared to be indifferent to subadult females. When the adult females returned, the males never attacked the females physically, but instead often emitted herding sounds to them. One subadult female was repelled by a resident adult female. When one adult female transferred into a new one-male group, she left her behind son in an all-male group. The number of females often fluctuated in most study groups, with this fluctuation being more prominent among subadult females than adult females. It is likely that female transfer in proboscis monkeys is not a rare occurrence and that it is especially common among sub-adult females.     

Sex ratio and maturity indicate the local dispersal and mortality of adult stoneflies

1. Despite a recent upsurge in interest, there remains remarkably little information about the dispersal and survival of the adults of most stream‐dwelling insects, although this is a basic requirement for understanding their long‐term population dynamics. 2. Using Malaise traps for a whole annual flight period, we captured adult stoneflies (Leuctra nigra) along transects perpendicular to three upland Welsh streams. We assessed spatial and temporal patterns in sex ratio to infer local dispersal and, using maturity as an age marker, estimated the mortality of adult females. 3. Nearly all adult stoneflies (99%) were taken in the period 26 April–23 July, and the onset of the male and female flight periods was the same. Most males (90%) had been caught by late June. Females were classified as immature (without ripe eggs) or mature, and 90% of immature females had been caught by mid‐late June (depending on catchment). As immature females declined in the catch, mature females increased, 10% having been caught by late‐May to early June and 90% by early to mid‐July. The median catches of immature and mature females were separated by 32 days in all three catchments. 4. There was a female bias in the sex ratio overall, which increased as time passed and was attributable partially to the greater longevity of females. Late in the flight period, however, female bias was also greater near the stream channel implying a return of mature females (but not males) from the riparian vegetation, presumably to oviposit. 5. The number of mature females was less than the number of immatures in two of the three channels. Over all three catchments, the overall mortality of females over the 32 days taken to mature was estimated at 29%, equivalent to an exponential daily rate of 1.1% day^?1. The apparently negative mortality rate in one catchment (i.e. more matures than immatures being caught) could be due to an influx of adult females from elsewhere along the channel to oviposit. 6. Natural markers of age and population structure, such as sex ratio and female maturity, thus enabled us to detect a return of females to the stream to oviposit, after prior limited dispersal into the riparian zone, and to infer longitudinal movements in search of suitable sites. We were also able to estimate mortality in the field. Such natural markers seem to have been underexploited in the study of adult aquatic insects.     

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.     

Social interactions among adult male langurs (Presbytis entellus) at Rajaji Wildlife Sanctuary

A population of langurs (Presbytis entellus)at the Rajaji Wildlife Sanctuary in northern India was investigated for 1820 hr throughout a 10-month period in 1978. Data were collected from four bisexual troops and the adult males that ranged outside of bisexual troops. Most (60%) of the observation hours occurred with a main study troop from which social and ecological data were collected. The langur population at Rajaji shows pronounced birth and mating seasons. The population density is high (ca. 80/km ²), with about 75% of the adult males living outside of bisexual troops, which typically are large and multimale. Males outside of bisexual troops occur in small all-male bands or as isolates. Relations between bisexual troops and all-male bands are characterized by relatively low levels of aggression, and members of all-male bands are able to associate with bisexual troops for prolonged periods during the mating season. As a result of these associations, nontroop males are about as successful as troop males in achieving reproductive access to troop females. These associations between bisexual troops and all-male bands occurred with a minimal amount of agonistic behavior and without mortality or injury to troop females or immatures.     

ECOLOGY AND BEAVIOUR OF THE VERVET MONKEY, CERCOPITHECUS AETHIOPS, LOLUI ISLAND, LAKE VICTORIA

A 1-month survey of the vervet monkeys of Lolui, an uninhabited island of 11 square miles in Lake Victoria, indicated a population size of about 1,500. Reliable counts of 46 groups were made, giving a mean of 12. Age and sex analyses of 18 groups showed a ratio of 1: 1.4 adult males to adult females, 1: 1 for adults and immatures combined.     

Post-conflict Social Events in Wild Mountain Gorillas. II. Redirection,Side Direction,and Consolation

Inevitably, members of primate groups sometimes have aggressive contests with each other. Targets of aggression can engage in several types of interaction with third parties to ameliorate its adverse effects. They can redirect aggression, which may reduce the risk of further aggression from the initial opponents and reduce tension, or they can initiate affinitive interactions with third parties, in order to seek protection or reassurance. They can also receive reassuring acts from them (‘consolation’). Researchers have documented high levels of redirection in many primate species, but consolation is thus far known only in chimpanzees. Data on post-conflict social interactions between targets of aggression and third parties in two groups of wild mountain gorillas (Gorilla gorilla beringei) show that immatures and subordinate males, but not females, redirect aggression at high rates. Furthermore, immatures seek affinitive interactions with their mothers, and adult females seek them with adult males, at elevated rates. Affinitive interactions between females and males seem mainly to have a protective function and are associated with decreased risks of further aggression between female opponents. Redirection by females after female-female conflicts may be uncommon because targets commonly retaliate against aggressors. Males may offer females protection and consolation as services, and the results support the argument that such services are important when dominance relationships between females are often undecided and retaliation between opponents is common.     

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.     

Population Density and Home Range Size of <Emphasis Type="Italic">Indri indri</Emphasis> in a Protected Low Altitude Rain Forest

We report the results of a census of Indri indri conducted in Betampona Nature Reserve, a lowland rain forest in eastern Madagascar. In addition, we conducted a year-long study of the ranging behavior of 3 groups in the southwestern region of the reserve. We used 2 methods to calculate population density and home range size, and to provide minimum and maximum estimates. Population density of Indri indri ranged from 6.9–13.2 individuals/km² in Betampona. Mean home range size is 27 ha. The values for population density and home range size are intermediate between values for Indri indri in selectively logged and undisturbed montane rain forest. Our results suggest a relationship between habitat disturbance, population density and home range size for the species. Recent increases in habitat disturbance appear to cause an increase in population density and a decrease in home range size. The results are consistent with ones for other folivorous primate populations. Further research on habitat requirements of Indri and availability in Betampona is necessary to investigate the possibility of translocating Indri from nearby forest fragments into Betampona.     

Group size and group composition of the mona monkey (Cercopithecus mona) on the Island of Grenada,West Indies

Cercopithecus, the genus of guenons, is the largest of the African primate genera, and yet more than half of the species belonging to this group have never been the focus of a long-term field study. In this paper, I present data on group size and composition for a previously unstudied population of guenons on the Caribbean island of Grenada. The mona monkey, Cercopithecus mona, was introduced to Grenada from Africa approximately 200–300 years ago. Two types of social groups were found for Cercopithecus mona on Grenada: all-male groups consisting of two to four individuals and bisexual groups containing 5–32 individuals. All-male groups of Grenada mona monkeys contained any combination of juveniles, subadults, and/or adults. All-male groups were a common occurrence on Grenada but have never been reported for African C. mona and have been reported only in two other forest Cercopithecusspecies. Bisexual groups appeared to consist of one adult male, one to six adult females, subadult females, and juveniles and infants of both sexes. Even though no more than one adult male was ever seen in each bisexual group of monas on Grenada, other males were heard giving copulation calls simultaneously with resident adult male loud calls, suggesting that other males occasionally infiltrate bisexual groups. Am. J. Primatol. 43:167–173, 1997. © 1997 Wiley-Liss, Inc.     

Population ecology of rhesus monkeys (Macaca mulatta) at Nanwan Nature Reserve,Hainan, China

Rhesus monkeys (Macaca mulatta) at the Nanwan peninsula of Hainan Island, China, have been observed in the field for 25 years, and have been studied intensively for eight years, beginning in 1981. There were about 115 monkeys in 5 natural groups when the Nanwan Reserve was founded in 1965. From 1965 to 1984, the number of groups increased from 5 to 19, and the total population increased from 115 to 930 individuals, an annual population increase of 12.7%. From 1984 to 1987, the population continued a slower rate of increase (8.9%) to approximately 1200 monkeys in 20 groups. The home ranges of each monkey group at Nanwan varied from 0.16 to 0.72 km², with a mean and standard deviation of 0.37 ± 0.18. The size of the home range of the rhesus was affected by the quality of vegetation and rhesus population density. The average birth rate per year was 77.8 ± 13.9%, varying from 53.8% to 100% since 1978. From 1978, the birth rates of two food provisioned groups were higher in alternate years (x? = 91.7%) and lower in intervening years (x? = 68.8%; P = <0.01). A minority (26.5%) of females have given birth at 4 years of age, most at 5 years. The sex ratio of newborns in any one year varied from 0.3 to 3.5 males to females, with a mean and standard error of 1.09 ± 0.37 males to females.     

Demography and Life Histories of Sympatric Patas Monkeys, <Emphasis Type="Italic">Erythrocebus patas</Emphasis>, and Vervets, <Emphasis Type="Italic">Cercopithecus aethiops</Emphasis>, in Laikipia,Kenya

Mortality patterns are thought to be strong selective forces on life history traits, with high adult mortality and low immature mortality favoring early and rapid reproduction. Patas monkeys (Erythrocebus patas) have the highest potential rates of population increase for their body size of any haplorhine primate because they reproduce both earlier and more often. We report here 10 yr of comparative demographic data on a population of patas monkeys and a sympatric population of vervet monkeys (Cercopithecus aethiops), a closely related species differing in aspects of social system, ecology, and life history. The data reveal that 1) adult female patas monkeys have significantly higher mortality than adult female vervets; 2) infant mortality in patas monkeys is relatively low compared to the norm for mammals because it is not significantly different from that of adult female patas monkeys; and 3) infant mortality is significantly higher than adult female mortality in vervets. For both species, much of the mortality could be attributed to predation. An epidemic illness was also a major contributor to the mortality of adult female patas monkeys whereas chronic exposure to pathogens in a cold and damp microenvironment may have contributed to the mortality of infant vervets. Both populations experienced large fluctuations during the study period. Our results support the prediction from demographic models of life history evolution that high adult mortality relative to immature mortality selects for early maturation.     

Status and Distribution of Macaca fascicularis umbrosa in the Nicobar Islands, India

We surveyed the distribution and status of the long-tailed macaque (Macaca fascicularis umbrosa) in the Nicobar Islands of India. Long-tailed macaques live on 3 islands: Great Nicobar, Little Nicobar and Katchal. There are a total 788 groups. Group size ranged from 25 to 56 individuals with a mean size of 36. Long-tailed macaques are a multimale-multifemale society. Adult males, adult females and immatures constituted 9.7 per cent, 43.2 per cent and 47.1 per cent of the population, respectively. A fairly high ratio of immatures to adult females indicates a healthy population turnover. Vegetation parameters including tree density, canopy cover, canopy height and basal area indicated a still healthful habitats on all the 3 islands. We observed a few threats to the macaques. Measures should be undertaken to ensure survival of the Nicobar subspecies.     

Cage design and configuration for an arboreal species of primate

The squirrel monkey (genus Saimiri) is an arboreal primate from equatorial South America. This species forms large social groups that consist of multiple females and males of varying ages, from infant to adult. As the use of squirrel monkeys in research continues to grow, an understanding of optimal cage design and environment is essential. The University of South Alabama Primate Research Laboratory houses a breeding colony of 350 squirrel monkeys. Each group cage, measuring 4.5 X 2.5 X 1.5 meters, can contain up to 20 animals. A breeding group consists of one adult male, eight to ten adult females, and varying numbers of infant and juvenile animals. In order to determine the most suitable cage environment for the squirrel monkey, a series of studies were carried out to compare various perch materials and cage configurations. Squirrel monkeys preferred a poly-vinyl-chloride pipe perch (rigid) over rope perches (non-rigid). When provided with multiple levels of perches, all levels were used. Males tended to distribute their activities randomly at different levels. In a two tiered perch arrangement, females concentrated 67% of their social activity on the top tier. In a triple tier configuration, females concentrated 66% of their travel on the top tier. These results indicate that by creating a cage environment with multiple tiers of horizontal perches the effective cage space can be doubled or tripled. This provides an effective means of reducing population density without enlarging the dimensions of the cage or reducing social group size.     

Two girls for every boy: The effects of group size and composition on the reproductive success of male and female white-faced capuchins

Many factors have been hypothesized to affect the size and adult sex ratios of primate groups and these, in turn, have been argued to influence birth rates. Using park-wide census data collected on a population of capuchins over a 25-year period, we examined whether group size and adult sex ratio affect the per capita reproductive success of male and female white-faced capuchins (Cebus capucinus) in Santa Rosa National Park, Costa Rica. We found that the reproductive success of females (measured as the observed minus the expected ratio of immatures to adult females in the group) decreased with increasing group size, whereas that of males was independent of group size. The proportion of adult males residing in groups had significant, yet contrasting effects on males and females. Male reproductive success was negatively associated with the proportion of males residing in groups whereas female reproductive success increased with the proportion of males. The latter finding supports the intersexual conflict hypothesis, which suggests that a conflict of interest occurs between males and females over adult sex ratios. The effects of group size and composition on the reproductive success of capuchins, a male-dispersed omnivorous species, are similar to those reported for howlers, a bisexually-dispersed folivorous species. One common factor between these taxa is that groups with low ratios of males to females are at greater risk of takeovers and resultant infanticide. Our results suggest that regardless of dietary preference and dispersal pattern, the threat of infanticide can constrain primate group size and composition.