Wild felid diversity and activity patterns in Sabangau peat-swamp forest, Indonesian Borneo

AbstractA study to identify the felid biodiversity of the Sabangau Forest, Central Kalimantan, Indonesia, was initiated in May 2008 and involved continuous sampling until October 2009. A total of 44 cameras in 27 locations were used and 5,777 functional trap nights (of 6,542 survey nights) resulted in confirmed sightings of the Sunda clouded leopard Neofelis nebulosa, leopard cat Prionailurus bengalensis, marbled cat Pardofelis marmorata and flat-headed cat Prionailurus planiceps, representing four of the five wild felids of Borneo. The long-term use of fixed and roving cameras provided insight into the movements, occurrence and activity patterns of these elusive felids within a disturbed peat-swamp forest. In an area of 145 km2 (including buffer) the clouded leopard was the most commonly photographed felid (22 photo-captures of 53 total captures), followed by the leopard cat (21), flat-headed cat (7) and marbled cat (3). A total of 231 camera-trap nights were required to obtain the first photograph of a felid, the leopard cat, 704 for the clouded leopard, 3,498 for the flat-headed cat, and 5,423 (476 calendar days) for the marbled cat. A female clouded leopard was not photographed until 5,764 trap nights. This highlights the importance of long-term camera-trapping studies to maximize capture probability of these elusive felids and especially to account for potential differences in home range size and use by clouded leopard males and females.</jats:p

Coming down from the trees: is terrestrial activity in Bornean orangutans natural or disturbance driven?

The orangutan is the world's largest arboreal mammal, and images of the red ape moving through the tropical forest canopy symbolise its typical arboreal behaviour. Records of terrestrial behaviour are scarce and often associated with habitat disturbance. We conducted a large-scale species-level analysis of ground-based camera-trapping data to evaluate the extent to which Bornean orangutans Pongo pygmaeus come down from the trees to travel terrestrially, and whether they are indeed forced to the ground primarily by anthropogenic forest disturbances. Although the degree of forest disturbance and canopy gap size influenced terrestriality, orangutans were recorded on the ground as frequently in heavily degraded habitats as in primary forests. Furthermore, all age-sex classes were recorded on the ground (flanged males more often). This suggests that terrestrial locomotion is part of the Bornean orangutan's natural behavioural repertoire to a much greater extent than previously thought, and is only modified by habitat disturbance. The capacity of orangutans to come down from the trees may increase their ability to cope with at least smaller-scale forest fragmentation, and to cross moderately open spaces in mosaic landscapes, although the extent of this versatility remains to be investigated

Hierarchical position of individual captive western lowland gorillas Gorilla gorilla gorilla and its impact on neighbour associations and behaviour

This study investigated the social relationships observed within a captive breeding group of western lowland gorillas Gorilla gorilla gorilla at a European Association of Zoos and Aquaria (EAZA) accredited facility: Blackpool Zoo, UK. Gorillas are complex and intelligent primates, and the western lowland sub-species is popular in zoo collections. Captivity can raise issues for gorillas which, in the wild, live in large family groups with a distinct hierarchy forming the basis of group stability. Studying captive groups can help facilities make informed decisions for gorilla captive management. This study considered if and how captive gorilla behaviour could be influenced by social positioning. It was carried out in May–July 2018 and focused on social behaviour, nearest neighbour and position in the enclosure recorded for focal individuals with notes on enclosure design taken. Interval focal sampling was used to record gorilla (n=6; two adult females, one adult male, two juvenile females and one infant male) social behaviour, their nearest neighbour (the animal physically closest to the focal individual) and position in the enclosure simultaneously every 10 min, during six-hour observation periods over two months. A different individual was observed daily. Data on independent and social behaviours were collected to determine activity budgets using an ethogram. Data on independent behaviours can demonstrate if there are variations in behaviour when gorillas are in social proximity. Mann-Whitney U tests were conducted on mean frequencies of independent (n=10) and social (n=5) behavioural categories for each individual. Independent inactive behaviours were most common (n=53.6) with adult gorillas displaying increased levels of sitting and lying in comparison with younger individuals. There is a difference among the gorillas in their social behaviour. Nearest neighbour data were analysed using cluster analysis. The silverback was most closely associated to his youngest offspring and lactating female. The sub-adult female has the weakest associations in comparison to the rest of the group. The results suggest individual preferences for social associations, with younger individuals associating closely with their mothers, and a mother and infant associating closely with the silverback. A sub-adult female was less associated with all individuals, which could suggest her readiness to transfer. This study emphasises the influence that hierarchical social organisation within a captive setting has on captive gorilla behaviour monitoring in general, relating to how individual gorillas manage their position in a hierarchical group. This study also provides specific suggestions for gorilla management within the centre and in conjunction with BIAZA guidelines, including a suggestion to relocate the sub-adult female to a new group and considerations for aggression mitigation

Ape Population Abundance Estimates

This annex presents ape abundance estimates at the site level. The term &ldquo;site&rdquo; refers to a protected area and its buffer zone, a logging concession or group of concessions, or any discrete area where a survey has taken place in the past two decades, although this annex also lists a few sites that were last surveyed in the 1970s and 1980s.Output Type: Online-only anne

Ape socioecology

First paragraph: This section presents an overview of the socioecology of the seven species of nonhuman apes: bonobos, chimpanzees, gibbons (including siamangs), eastern and western gorillas, and Bornean and Sumatran orangutans. For more detailed information, see Wich et al. (2009b), Emery Thompson and Wrangham (2013), Reinartz, Ingmanson and Vervaecke (2013), Williamson and Butynski (2013a, 2013b), and Williamson, Maisels and Groves (2013)

Behaviour of Wild, Non-Adult Bornean White-Bearded Gibbons (Hylobates albibarbis) in Indonesia

Primates have an extended juvenile period associated with critical social and environmental learning. In particular, social play is positively associated with brain size in primates, indicating an important role in cognition and development. However, this behaviour has been overlooked in the Hylobatidae family. The activity patterns of eight non-adult Bornean white-bearded gibbons (Hylobates albibarbis) from four groups were studied in the Sebangau peat-swamp forest in Borneo from 2005 to 2019. We compare our findings to previous reports for adult conspecifics, report the directionality of non-adult play behaviour, and examine whether the weather impacts daily activity patterns. Feeding (39.5%), resting (27.6%) and travelling (23%) were the main activities of juveniles, while infants mostly played (42.1%) or clung to their mothers (38.3%). Non-adult groups socialised and observed their surroundings more often, and they travelled and called less often than adults. Feeding and resting frequency did not differ significantly from that of adults. Infants engaged in self-centred play twice as often as juveniles and directed most of their playing attention towards sub-adults (58%). Weather variables, previously reported to be good predictors of certain adult activities, such as singing, did not appear to affect infant and juvenile activities. Play is a critical part of primate physical and social development, and this study describes some key behaviours of young gibbons. Understanding the play behaviour of gibbons in the wild will help inform the rehabilitation of an ever-increasing number of orphaned individuals who are victims of the illegal pet trade