With about 50 species and subspecies, the diversity of primates in Peru is amongst the highest in the world. Primate field surveys, however, are still scarce for many areas. Peru's northern forests lie at the heart of the Tropical Andes and are home to four of the country's endemic primates: Aotus miconax, Callicebus oenanthe, Oreonax flavicauda, and Saguinus leucogenys. We present here an overview of results from more than five years of primate surveys in northern Peru. Surveys were carried out in the valleys and intervening highlands between the ríos Marañón and Huallaga in the departments of Amazonas, La Libertad, Huánuco and San Martín. Data were gathered between March 2007 and October 2012 from 36 locations at 26 sites. Surveys were carried out as part of biological inventories in proposed conservation areas. In all, 14 species were recorded from 11 genera. The presence or absence of a species was largely determined by altitude. The four endemic species were present in the majority of survey sites. The most common species encountered were Oreonax flavicauda, Ateles belzebuth, Cebus yuracus, and Aotus miconax. The highest species diversities were found at lower altitudes further from human development, although some species previously registered in these regions were not encountered. All areas visited suffered from at least some anthropogenic disturbance, with the majority showing high levels of habitat disturbance, deforestation and hunting.

Neotropical Primates are threatened because of deforestation and hunting. There are numerous species and subspecies of primates today restricted entirely to small forest patches. Many are poorly studied due to the remoteness of their ranges, political situations, or the expensive logistics required. Although population surveys are important to obtain baseline information for the conservation of threatened primates, there are opportunities where population censuses could be used in conjunction with rapid conservation strategies. In this report we encourage scientists to use collateral techniques that could positively impact local communities while undertaking scientific studies. They include the involvement of biology students from the target country, the use of informative material to divulge information on the natural history and conservation of the target species, and the creation of interest among community leaders so that a long-term conservation program can be established in the future.

The northern sportive lemur, Lepilemur septentrionalis, faces imminent danger of extinction, more so than any other lemur in Madagascar. The population estimates for this sportive lemur remain unknown because of habitat loss and ongoing human encroachment, but they are unlikely to number more than a few hundred individuals. We present the results of extensive surveys conducted in 2010, 2011 and 2012 of known habitat, the Sahafary and Analalava classified forests, and confirm the species designation of the sportive lemur observed in Montagne des Français in 2007. Six L. septentrionalis individuals were examined in Sahafary in 2011, along with eight individuals during the 2010 and 2011 expeditions to Montagne des Français. A July 2012 survey in extended forest fragments of Montagne des Français identified another 10 individuals. Surveys of the Analalava forest in 2011 detected no northern sportive lemurs, despite documenting their presence in 2005. One individual was recorded in the July 2012 survey. Although the morphological data of the sportive lemurs at Montagne des Français was comparable to that of Sahafary, the sportive lemur at Montagne des Français was subsequently verified as L. septentrionalis with mitochondrial DNA D-loop sequence data analyses. The confirmation of the northern sportive lemur at Montagne des Français is significant since it establishes additional habitat for this species. However, sustained human encroachment from Antsiranana continues to finance the production of charcoal and collection of sand; activities that are threatening this population. Habitat loss and hunting continue to be the principal threats to the long-term survival of the northern sportive lemur. With only 19 known individuals, we urge immediate conservation action for this Critically Endangered species.

The greater bamboo lemur Prolemur simus is a Critically Endangered lemur endemic to eastern Madagascar. Wild P. simus populations have diets dominated by bamboo (Poaceae: Bambusoideae), particularly large-culmed species of two endemic genera, Cathariostachys and Valiha, but also of an endemic Arundinaria and the pantropical Bambusa vulgaris. A good understanding of the distribution and biology of large-culmed bamboos would, therefore, be a major help in understanding the factors influencing the distribution and conservation requirements of P. simus. During four years of research within the context of a collaborative programme aimed at conserving P. simus, we undertook surveys at 47 low-, mid- and high-elevation sites in eastern Madagascar between November 2008 and September 2012, covering a distance of over 1000 km from Makira in the north to Midongy in the south. We provide and illustrate characteristics helpful in the field identification, at least to generic level, of the large-culmed woody bamboos we encountered. The most frequently encountered non-endemic large-culmed bamboo was Bambusa vulgaris, with both the green and the yellow forms commonly planted in or near rivers, towns and villages. We made 1,343 georeferenced records of endemic, large-culmed bamboos, recording Cathariostachys from Makira to Midongy, Valiha diffusa from Makira to the southern parts of the COFAV, and Arundinaria from Zahamena to the COFAV. Valiha diffusa was recorded only at low elevations (9–576 m), and Arundinaria only at high elevations (1018–1667 m), while Cathariostachys was distributed across a wide range of elevations, from 53 to 1471 m, although most records were between 600 and 1,260 m. Valiha diffusa had the most variable culm diameters, ranging from 1.7 to 9.5 cm. Cathariostachys had the largest mean culm diameter of the endemic large-culmed bamboos (6.1 cm), and Arundinaria the smallest (4.0 cm). Culm diameters of Bambusa vulgaris were larger than those of the endemic bamboos, with a mean of 9.58. Cathariostachys had thinner mean culms at lowland compared to higher elevation sites. The revised distribution map we provide for Cathariostachys appears to correspond well to the potential current distribution of P. simus based on recent direct sightings, indirect feeding signs and unconfirmed local knowledge. Cathariostachys does not, however, currently occur throughout the historic range of P. simus. Valiha does occur at one P. simus subfossil site outside the current range, and therefore may have been the primary food source for the species there. Further research into the historical distribution of large-culmed bamboos in Madagascar would be very helpful in establishing how eventual changes in bamboo distributions over time may have affected changes in P. simus distribution.

In South Africa, conflict between humans and vervet monkeys (Chlorocebus aethiops) has led to large numbers of the species coming into care in rehabilitation centers. An accumulation of displaced vervet monkeys in such centers has necessitated the process of troop formation and release. To date, the quality of methods used has been variable, as have the outcomes of rehabilitation and release efforts. Here we present proposed guidelines for the rehabilitation and release of vervet monkeys based on studies of vervet monkey rehabilitation, behavior and biology, in conjunction with existing guidelines for nonhuman primate reintroductions produced by the International Union for Conservation of Nature (IUCN). The aim of these guidelines is to facilitate improved rehabilitation, release, and post-release monitoring and assessment, with the ultimate goal of improving release outcomes.

We censused two discrete subpopulations of the endangered Zanzibar red colobus (Procolobus kirkii) and sympatric Sykes's monkeys (Cercopithecus mitis albogularis) between February 2004 and September 2005 in two coastal forests in Zanzibar, including the northernmost (Kiwengwa-Pongwe Forest) and some of the southernmost (Uzi and Vundwe Islands) extents of P. kirkii's range. Surveys totalled 365 hours and 307.8 km along >16 km of line transects; 472 sightings were made (Red colobus n = 252; Sykes's monkey n = 220). The southern forests (coral rag with adjacent mangrove) of Uzi and Vundwe Islands were found to support P. kirkii at a higher estimated density (29.6 groups/km²) relative to the northern coral rag forest (lacking mangrove) in Kiwengwa-Pongwe (7.5 groups/km²). However, for red colobus in coral rag, up to c.40% of these “groups” could be “sub-groups” based on our observations of consistent fission-fusion and small groups seen during the census (6.63 ± 0.4SE in Kiwengwa, 6.64 ± 0.33SE in Uzi) and behavioral follows in this habitat type. We therefore also include density estimates expressed as individuals/km² (49.72 individuals/km² in Kiwengwa, 196.32 individuals/km² in Uzi). On Uzi and Vundwe Islands, colobus densities were higher than those of Sykes's monkey (Sykes's monkey density = 18.9 groups/km²), while we found no difference between the density of these two taxa in Kiwengwa (Sykes's monkey density = 8.1 groups/km²) where encounters with humans were more frequent, vegetation was more disturbed, and the two species often associated. Although these populations represented a fraction of the historical total population of red colobus and Sykes's monkeys on Zanzibar, their estimated abundance was significant, and their marginal habitat and unprotected status were important in the general context of primate conservation in unprotected and fragmented landscapes.

The golden langur (Trachypithecus geei), which only became known to science in 1953, is endemic to western Assam, India, and southern Bhutan. The Indian population had been greatly depleted due to a fragmented range and the species was declining radically in 1997 with a pessimistic view for its future. The Golden Langur Conservation Project was begun in 1998 with the goal of protecting the golden langur within its entire Indian range. At the time of the project's initiation, the species was considered India's most endangered primate due to limited range and major deforestation (50%) as a result of a complex political situation from militants in the forest threatening the Assam Forest Department staff, and ethnic violence. The project worked with regional non-governmental organizations and government agencies using the following tools to effect conservation contagion: 1) community meetings; 2) involving villages in forest committees and “Self Help Groups” for economic development; 3) formal seminars; and 4) celebratory events for the creation of the Manas Biosphere Reserve. The project developed conservation contagion, resulting in villages creating their own conservation groups to participate in the project, eventually resulting in 18 community groups forming Forest Protection Forces collectively, under the Unified Forest Conservation Network, to protect almost the entirety of the Manas Biosphere Reserve as well as other reserve forests in Assam. This community protection resulted in an increase of the Indian population of golden langurs from c.1,500 in 1997 to c.5,600 langurs in 2007 to 2012. The project also resulted in the lifting of the “in danger” listing for the Manas Biosphere Reserve by UNESCO. The Indian population of golden langurs mainly resides in the Manas Biosphere along the Bhutan border and in a number of southern isolated reserve forests north of the Brahmaputra River. In adjacent Bhutan, the southern subspecies is contiguous with its Indian counterpart and with the northern subspecies, which has more gray on its arms and tail and inhabits higher altitudes. The Bhutan population is grossly estimated at over 6,600 langurs based on a population census of 60 km², giving a total estimate for the species in Assam and Bhutan of over 12,000 individuals. The potential for community conservation in Bhutan is also discussed.

The western hoolock gibbon Hoolock hoolock is globally threatened because of a combination of habitat loss, fragmentation and hunting. Most remaining populations are isolated and contain few individuals. We studied a small population of western hoolock gibbons in Dampa Tiger Reserve in Mizoram, India, an area with a deep-rooted tradition of hunting wildlife. We quantified differences in 35-ha sites that were used by gibbons (n = 9) with those that were not (n = 6). We found no statistical differences with respect to canopy continuity, distance to the nearest village or levels of habitat disturbance, but were not able to quantify levels of hunting. Interviews with local villagers (n = 53) from seven villages distributed throughout the reserve suggests that gibbon numbers declined progressively from the early 1970s to the present day, possibly from >100 to <50 individuals. Interviewees pointed at the combined result of fire (from, for instance, slash-and-burn cultivation), reduction of the available habitat, and hunting, exacerbated by an increase in the human population, as possible causes. This corresponds well with our analysis of vegetation maps of the reserve based on satellite imagery, that show a decline in suitable habitat from 63% of the reserve in 1978, to 59% in 1989, and 50% in 2005. We strongly recommend a greater emphasis on quantifying the impacts of hunting on the distribution and persistence of hoolock gibbons.

The endangered and endemic lion-tailed macaques (Macaca silenus) of the rainforest fragments of Valparai plateau in the Western Ghats Hotspot (India) are facing serious threats to their survival due to anthropogenic pressures and habitat degradation. In this study, we identify potential wildlife corridors between the rainforest fragments and adjacent more extensive forest areas so as to connect isolated lion-tailed macaque populations. Satellite datasets were used to delineate the forest fragments and assess the conditions of the surrounding landscape. The corridors were selected on the basis of minimal impact on human settlements, agricultural areas and other infrastructure, as well as to enhance ecosystem services. The results show that a minimum area of 156 ha is required to connect three isolated lion-tailed macaque populations to the adjacent forest area. This includes 54 ha of seasonal stream beds (low human-use areas), 99 ha of cultivated area (medium human-use areas) and 3 ha of roads, settlements and built-up areas (high human-use areas). This methodology for identifying wildlife corridors in highly fragmented landscapes of the Western Ghats can also be applied to other human-dominated landscapes, including biodiversity hotspots.

Sri Lanka's western purple-faced langur (Semnopithecus vetulus nestor) is Critically Endangered, mainly because of habitat loss due to deforestation. Reforestation to expand the langur's natural habitat became feasible when the present government mandated the use of native plants to increase the country's forest cover. For reforestation to benefit langur populations, however, the re-created habitat needs to be similar to the natural forest that provides food and space for their survival. This monkey's diet and the manner in which it uses its natural habitat are, therefore, being investigated as the first step. The diet and habitat use patterns of two groups, Tikira and Appu, were studied for 13 and 14 months respectively (n = 1695 hours). Scan sampling (with ten-minute sample periods) was used to record all activities observed in the groups and the trees on which these activities were performed. The plant parts eaten were also noted. Our results showed that Tikira used more species than Appu to perform all of its daily activities. Additionally, while the Tikira group used Dipterocarpus zeylanicus most frequently during most months, the Appu group had six species occupying the top rank during different months. Of the ten most frequently used species, only five were common to both groups, and the frequency of use of these plants was sometimes quite variable as well. With respect to diet, Appu used at least 27 species while Tikira fed on more than 41. The top-ranking food plants of the two groups were different, and among the top ten only four were the same. The top fifteen food plants of both groups constituted over 85% of their feeding records. Nineteen species eaten by Appu and 29 eaten by Tikira were exploited for less than two months, and the two groups ate no more than five species for more than seven months of the study. Although the two groups relied on different plants for much of their nutrition, nearly 86% and 74% of feeding observations of Appu (n = 422) and Tikira (n = 685), respectively, were of them feeding on leaves. Blossoms, fruits and petioles made up the remainder of the groups' diets. While these items contributed variable amounts to the monthly diet of both groups, none was exploited more frequently than leaves. The above results are compared to information from other non-human primates, and discussed with respect to reforestation. Two points are emphasized. One is that the langur living in its natural habitat is a typical folivore, unlike those living around home gardens. The other is that while field research is essential to reforest degraded habitats it must be conducted in conjunction with conservation education and other initiatives that are designed to dissuade people from destroying restored and intact natural habitats.

The bonnet macaque Macaca radiata, endemic to peninsular India, is typically ignored in conservation initiatives as it is considered a common species, ubiquitously present across its distribution. Recent studies in southern India, however, report drastic declines in its populations. From March to May, 2012, we carried out a study to investigate its conservation status at the northern end of its range, in the state of Goa on the western coast of India. We recorded bonnet macaques in less than 40% of the locations we visited where they had previously been reported, and found that local residents living in close association with bonnet macaque populations were largely intolerant of the species' presence. Surveys and studies to monitor the population dynamics of such ‘common’ species as the bonnet macaque are urgently needed so that we can be better informed about their actual conservation status.

Lowland tropical forest in the Lower Dibang Valley district in the state of Arunachal Pradesh is the prime habitat in India of the eastern hoolock gibbon (Hoolock leuconedys). The present study was conducted to assess the threats to the population of H. leuconedys in the unprotected forest fragments of the Lower Dibang Valley district, Arunachal Pradesh. Besides field observations, we employed a structured questionnaire survey method to interview villagers, including the Gaon Burha (village head) and local hunters. Based on our observations and the interviewees' responses, we recorded that gibbons were occasionally hunted for bushmeat, and that dogs, the Mountain Hawk Eagle (Nisaetus nipalensis), and monitor lizards (Varanus) were evidently predators of, particularly young, gibbons in the fragmented forest patches. Indirect threats included habitat destruction and fragmentation, deforestation, extraction of non-timber forest products, livestock grazing, road construction, selective (illegal) logging, shifting cultivation, commercial cash-crops, and permanent human settlement. A conservation action plan is urgently needed to protect and conserve the eastern hoolock gibbon from extinction in the region.

The lion-tailed macaque (Macaca silenus) is one of the most threatened of the primates of the Western Ghats. Confirmation of its large metapopulation in a relatively unprotected area (a reserve forest) of Karnataka has marked an important step for the future of this population. The number of lion -tailed macaques estimated was 638 in 31 groups with an average group size of 20.6, excluding lone males. A review of the literature confirms that this is one of the larger known populations in the wild. This reserve forest faces a number of threats because of anthropogenic activities such as habitat fragmentation, encroachment and developmental projects. In an attempt to save and restore the northernmost habitat of the lion-tailed macaque, we proposed that the forests where they live be declared a wildlife sanctuary or conservation reserve, using them as an umbrella species for conservation. In response to this, the forest department of the Government of Karnataka notified the proposed area, with only minor modifications to the boundary, as the ‘Aghanashini Lion-tailed Macaque Conservation Reserve’. We suggest some immediate management interventions to minimize further pressure on this highly threatened habitat.