The Azuero howler monkey, Alouatta coibensis trabeata, and the Azuero spider monkey, Ateles geoffroyi azuerensis, are endemic to the Azuero Peninsula, southwestern Panama, Central America and they are considered Critically Endangered. They are threatened by deforestation, poaching, and illegal trade. I carried out population surveys of the two subspecies from April 2001 to June 2009. The study covered potential habitats for these primates in the three provinces where they are believed to occur (Herrera, Los Santos and part of Veraguas). Surveys determined their occurrence and locations in each province. In all, 7,821 hrs were spent in survey activities. I used four methods: 1) Direct observation of presence/absence; 2) triangulations based on vocalizations; 3) strip-transect censuses, and 4) road counts. Forty-five Azuero howler monkey groups were seen and counted, totaling 452 individuals with a mean of 9.6 individuals/group, SE ±3.3 (range = 3–26). I estimate approximately 322 howler groups and c. 3,092 individuals remaining in the wild in the three provinces. For the Azuero spider monkey, 74 individuals in 10 sub-groups and five complete groups were counted directly, with a mean of 3.8 individuals/subgroup, SE ±0.6 (range 2–7) and a mean of 12.5 individuals/group, SE ±3.7 (range 10–22). Overall, I confirmed the existence of approximately 13 spider monkey subgroups and 145 individuals of A. g. azuerensis remaining in the wild in the provinces of Veraguas and Los Santos. It is already extinct in the province of Herrera. This study confirms that both subspecies are Critically Endangered. Each appears to have already experienced changes in group composition due to isolation and habitat degradation. Conservation measures based on educational awareness programs have been initiated.

We conducted a predictive GIS (Geographical Information System) analysis to create a realistic Habitat Suitability Model (HSM) and risk analysis throughout the distribution of the Andean titi monkey (Callicebus oenanthe) in order to evaluate the effectiveness of the current protected area (PA) network. This was done to help current conservation work and aid in the planning and implementation of future initiatives. Little was known about this species until recently. Callicebus oenanthe is listed as Critically Endangered on the IUCN Red List of Threatened Species. It is endemic to San Martín region, northeastern Peru. Our results show that the extent of habitat available for this species may be greater than previously thought but that habitat loss in the region is extremely high. GAP analysis indicates that the current protected area network is ineffective in protecting this species, and new reserve areas are urgently needed. We recommend further study into the species' ecology to better understand its needs and to aid in future conservation work.

The golden-headed lion tamarin, Leontopithecus chrysomelas, was formerly thought to range below 300–400 m above sea level, because of changes in forest physiognomy and lack of resources at higher elevations. We document four cases (from two studies) of L. chrysomelas ranging above 500 m, and investigate the behavior of two groups that ranged from 100 to 700 m. We discuss the possibilities that 1) resources may be more abundant at higher elevations than previously thought, 2) a shift may have occurred in the species elevation-use patterns in response to forest loss and degradation at lower elevations, and that 3) golden-headed lion tamarins require low elevations for access to resources but use higher altitudes to travel between lower lying areas. Understanding exactly how L. chrysomelas uses higher elevations and the limits of its upper ranging patterns has significant conservation implications for this endangered species. Even without being able to definitively ascertain that golden-headed lion tamarins are able to settle in stable home ranges at higher elevations with adequate resources for breeding and survival, they certainly move through these habitats. We suggest, therefore, that slopes and ridge-tops should be taken into account as corridors to be preserved for gene flow in the otherwise highly fragmented L. chrysomelas metapopulation.

In this study, I examined the skull morphology of three color phases of the Colombian Woolly Monkey Lagothrix lugens (Primates: Atelidae). Collecting localities of museum specimens were investigated through GIS-based modeling techniques to test for geographical and ecological patterns in L. lugens populations. Statistical analyses conducted on 28 craniomandibular measurements, in combination with the assessment of discrete characters, indicated that L. lugens consists of three geographic groups. The morphotype from the highlands of the Central Cordillera (>2,000 m altitude) matches in all characters the original description of L. lugens. There is a distinct morphotype from the lowlands of the northern Amazon (Department of Caquetá) and another from the piedmonts of the eastern versant of the Colombian Andes and the isolated mountains of the Serrania de la Macarena, herein recognized as new subspecies. The presence of an intermediate form between highland and lowland divergent lineages is also interpreted as indication of effective hybridization in a narrow contact zone at the Macizo de Garzón in the southernmost range of the Eastern Cordillera.

The Vondrozo-Midongy rainforest corridor in south-eastern Madagascar is an example of a habitat corridor between otherwise disconnected protected areas, and is therefore considered important for the conservation of the endemic biodiversity of the island. Through several years of collaboration with local communities surrounding this corridor, WWF-Madagascar learned that members of some of these communities claimed the existence there of the black-and-white ruffed lemur (Varecia variegata) and the greater bamboo lemur (Prolemur simus), both regarded as Critically Endangered by the IUCN and not known by the scientific community to be present in the corridor. We therefore surveyed six sites in three communes in May 2010 to confirm this information. We made direct observations of Varecia variegata at two sites, which represent a southern extension to the known range of the species. We also found the characteristic feeding remains of Prolemur simus in the three most southerly sites, observations which also represent a major southern extension of the known range of this species. However, the feeding signs we found were old, at least a year old by our estimations, so we recommend further research to ascertain whether the population still exists there. The corridor is threatened by many anthropogenic pressures, and further reinforcement of the conservation program for the corridor is therefore likely to be necessary to ensure the viability of endangered lemurs in the region, and the role of the corridor in ensuring biological connectivity between the more substantial forests to the south and north.

Increasing human populations and the rapid conversion of forest to agricultural land increase the likelihood of interactions and conflict between humans and nonhuman primates. Understanding such interactions requires a broad cross-disciplinary approach that assesses the implications of sympatry for primate conservation and human social, cultural and economic needs. Although chimpanzees were declared extinct in Guinea-Bissau in 1988, recent reports estimate that between 600 and 1,000 individuals are currently present, with the largest population occupying the Cantanhez National Park (105,700 ha; northeast limit: 11°22′58″N,14°46′12″W; southwest limit: 11°2′18″N,15°15′58″W). These heavily fragmented coastal forests have been identified as one of seven priority areas in West Africa for urgent chimpanzee conservation efforts (Kormos et al. 2003. West African Chimpanzees. Status Survey and Conservation Action Plan. IUCN, Gland. 2003). Here we set the context for human-chimpanzee sympatry in Guinea-Bissau, and provide a platform from which further studies can expand. We review past findings that might affect current and future sympatric relationships, and integrate preliminary data on resource competition from one hitherto unstudied chimpanzee (Pan troglodytes verus) community inhabiting a forested-agricultural matrix in Caiquene and Cadique, central Cantanhez National Park. While local human cultural traditions provide a degree of tolerance and protection to chimpanzees in Cantanhez National Park, which is beneficial for long-term conservation initiatives, human-chimpanzee interactions have the potential to grow increasingly negative in character, especially as human populations expand and further pressure is exerted on the land.

Tanzania is located at the southeastern end of the eastern chimpanzee (Pan troglodytes schweinfurthii) distribution. Except for two national parks, their habitats have been degraded due to human activities. To clarify the gene flow and genetic diversity of chimpanzees in Tanzania, we analyzed the mitochondrial sequences of chimpanzees in six sites (Lwazi, Wansisi, Mahale, Karobwa, Ugalla-Masito, and Gombe), some of which are now isolated. The southernmost habitat (Lwazi) was about 150 km away from the nearest habitat but, considering the geographic distance, the genetic distance of the chimpanzees between Lwazi and the other habitats was not high. In contrast, the genetic distance between the chimpanzees in the northernmost habitat (Gombe), and the other habitats was relatively high considering the geographic distance. The results suggest that the Malagarasi River, which runs between Gombe and the southern habitats, limits gene flow. The genetic difference analyses also suggest that the habitats of Wansisi, Mahale, Karobwa, and Ugalla-Masito can be regarded as one population (“Greater Mahale”). The genetic distance between Lwazi and Gombe was lower than that between Gombe and the Greater Mahale habitats. This result suggests that early chimpanzees came to the Greater Mahale habitats through the southern habitats around Lwazi. The nucleotide diversity was not different from that in other countries, probably due to the sequence variety. There were unique haplotypes in several habitats where the number of chimpanzees was estimated to be small, which implies that some haplotypes are probably be at risk of disappearing. These data will be useful for conservation planning.

The Indochinese silvered leaf monkey Trachypithecus germaini (perhaps comprising two species, T. germaini [sensu stricto] and T. margarita) is probably the rarest and most threatened monkey in Lao PDR. It has received less conservation-related attention in the country, however, than have the primates endemic to Indochina east of the Mekong because until recently it was generally considered conspetific with the widespread T. cristatus of Sundaic South-east Asia. All Lao records with firm locality details are from south of 16°23′N (in Dong Phou Vieng National Protected Area) and in lowland forests (up to 550 m above sea level), with many from near waterbodies. The predominant habitat seems to be semi-evergreen forest as patches and strips within a mosaic of more deciduous forest types, especially semi-evergreen forest in riparian and other waterside situations. Occupied semi-evergreen forest seems generally at the dry end of its spectrum, with a high deciduous tree component (this is the predominant type in interior plains-level Indochina), where this forest type grades to what some call mixed deciduous forest. Few if any records come from the interior of extensive unbroken semi-evergreen forest, or from highly-deciduous mixed-deciduous forest. Occupied areas include narrow stands flanking watercourses in deciduous dipterocarp forest, but there are no records from the more extensive deciduous dipterocarp forest matrix itself. Vague reports suggest occurrence up to 1,200 m, but given the high survey effort in such habitat, the species is at best very rare above the lowlands. Lao villager reports, and comparison with its status in similar habitats in adjacent Cambodia, suggest steep declines in Lao PDR. Suitable habitat (as profiled above) naturally covers only a small part of the southern Lao landscape, is among Lao PDR's most threatened habitats, and bears heavy hunting. Hence the great rarity of Indochinese silvered leaf monkeys compared with sympatric monkeys and gibbons, which inhabit the more extensive hill forests. There are records of the Indochinese silvered leaf monkey from only one Lao site since 2001. Although appropriate surveys during the 2000s have been limited, the species may now be extremely rare in the country and should join other, better publicized, bird and mammal species of these southern lowland plains landscapes as in need of urgent conservation action.

Phayre's leaf monkey Trachypithecus phayrei had fewer confirmed 1990s records in Lao PDR than any other monkey known from the country, suggesting a general rarity there. This review collates records, historical and recent, to evaluate its national conservation status. Although in no area have surveyors regularly and readily seen the species, records come from a wide scatter of areas in and north/west of Nam Kading National Protected Area to the far north and west of the country. There are inconclusive indications of occurrence up to 120 km south of confirmed records, but this part of the country is well enough surveyed that the animal must be very rare there, if it occurs at all. Much of North Lao PDR comprises ragged highlands over 800 m altitude, but only one Phayre's leaf monkey field record is from above this height (at 1,125 m). Whether this apparent altitudinal restriction is a natural pattern or reflects heavy hunting is unclear. Despite their lower-lying locations, records are not associated with gentle terrain. Most records come from forest with a heavily broken canopy and much tall bamboo; none is from deep within extensive closed-canopy forest. This might simply reflect the paucity of such forest within the known Lao geographic and altitudinal range, but a genuine habitat association with broken canopy and tall bamboo is likely. The status of Phayre's leaf monkey in Lao PDR is less grim than was feared a decade ago, and it inhabits three national protected areas, which are benefitting from long-term external collaboration. Nonetheless, its status in Lao PDR cannot yet be considered secure. Lao populations are probably relatively insignificant to the global status of T. phayrei as here taxonomically constituted.

The distribution and ecology of Assamese macaque Macaca assamensis remains little studied in South-east Asia. This review collates historical and recent records to clarify its range and habitat use in Lao PDR. Contrary to many standard sources limiting Assamese macaque's range to the north and center of the country, it occurs well into the southern part. In the country's three physiographic units, it is widespread in the northern highlands and the Annamite range, but seems absent from the Mekong plain. Most records are from hill evergreen forest above 500 m, consistent with standard literature, but the species occurs down to plains level (200 m) on karsts (at least in areas south of 16°58′N). The few records from below 500 m off karst are all in ragged terrain, but even so non-karst ragged land below 500 m seems to be only rarely used. Ecological overlap with northern pig-tailed macaque M. leonina and with Rhesus macaque M. mulatta is very limited in Lao PDR. In the long-term, hunting and forest encroachment may threaten Assamese macaque in Lao PDR, but it is much less imminently at risk in the country than are most gibbon and colobine species.

The southern purple-faced langur (Semnopithecus vetulus vetulus) is endemic to Sri Lanka and is listed as Endangered on the IUCN Red List. Following several decades of widespread deforestation in the country, viable habitat has been severely reduced for these arboreal, folivorous primates. Living close to densely populated human settlements has lead to further conservation difficulties. They have adapted to exploiting cultivated fruits in home gardens resulting in human-primate conflict, besides confronting electrocution hazards when crossing roads using power lines. The opening of the Colombo-Matara Expressway has also posed a threat, with the possibility of troops from either side becoming genetically isolated. Twenty-six troops were studied from 2007 to 2011 in the southwestern districts of Galle and Matara; of these, 14 contained one or more individuals with an atypical pelage coloration, which we call here a white color morph Two white alpha males were documented, along with adults, juveniles, and young of both sexes, totaling 30 individuals. The troops around Deniyaya and Getabarawa villages contained members that showed a distinct pelage, and all of the members of these troops had dissimilar cranial features and body size compared to other S. v. vetulus. Molecular analysis is now required to discover the genetic basis for this variation and any possible competitive advantages associated with its spread, with the possibility that this may originate a new subspecies. The discovery of a new color morph may provide an additional opportunity to promote primate conservation; greater national support is urgently needed considering the perilous future facing S. vetulus. Further research prospects and conservation recommendations are discussed in this paper.

In Bangladesh rhesus macaques (Macaca mulatta) are found in forested habitats and urban areas. From 2005 to 2010, we investigated the distribution of rhesus macaques throughout the country. Populations were estimated by line transect, point sampling and direct counting. A total of 37 groups in 16 localities were recorded in urban areas. Overall, group size in urban areas ranged from 22 to 91 individuals, with a mean of 41.3 ± 16.7. Rhesus macaques in urban areas were found mostly near Hindu communities. Nearly five times as many groups (n= 176) of rhesus were observed in the forested habitats of the country. Overall group size in natural habitats varied from 10 to 78 individuals, with a mean of 30.2 ± 10.9. Of the natural habitats, the northeast rainforests were found to support the largest groups (38.9 ± 10.3, n = 49), while smaller groups were found in the central deciduous forests (19.3 ± 4.7, n = 18). The adult sex ratio was higher (1 male to 2.86 females) and the ratio between adult and non-adult (immature) was lower (1 adult to 1.70 non-adults) in natural habitats than was found for the populations in urban areas (1 male to 1.93 females, and 1 adult to 2.11 non-adults). In urban areas, the human-monkey conflict is increasing as competition for resources intensifies.

Most of the information available on the conservation status of the ebony leaf monkey (Trachypithecus auratus), a species categorized as “Vulnerable” on The IUCN Red List, comes from studies conducted in Java. However, these findings may not be representative of other islands of the Indonesian archipelago, such as Bali. In order to estimate the density and abundance of the ebony leaf monkey population in Prapat Agung Peninsula, located in the northern part of the West Bali National Park, Indonesia, we used repeated line transect distance sampling, a standard method for census surveys of wild animal populations, including primates. The estimated group density, individual density, group size, and total population size were 0.95 group/km², 7.11 individuals/km², 7.49 individuals/group, and 422 individuals, respectively. The comparison of these values with those obtained from a previous study conducted 10 years ago in the same area and with the same method showed a marked decrease in population density and abundance as well as changes in the spatial distribution of ebony leaf monkeys. Our data suggest that such trends may be at least partially explained by anthropogenic disturbances, including illegal logging activities and habitat fragmentation. Given these alarming signs, and to better assess trends in the Balinese ebony leaf monkey populations change over time, we urge for the replication of the same survey design in the same study area, at least every five years. Such a survey effort is crucial not only to better understand the socio-ecology of ebony leaf monkeys, but also to determine conservation priorities and devise management plans related to the protection of the populations of this vulnerable primate species in Indonesia.