Sleeping trees and sleep-related behaviours of the siamang (Symphalangus syndactylus) in a tropical lowland rainforest, Sumatra, Indonesia
Authors: Harrison, N.J., Hill, R.A., Alexander, C., Marsh, C.D., Nowak, M.G., Abdullah, A., Slater, H.D. and Korstjens, A.H.
Pages: 63-75
DOI: 10.1007/s10329-020-00849-8
Abstract:Sleeping tree selection and related behaviours of a family group and a solitary female siamang (Symphalangus syndactylus) were investigated over a 5-month period in northern Sumatra, Indonesia. We performed all day follows, sleeping tree surveys and forest plot enumerations in the field. We tested whether: (1) physical characteristics of sleeping trees and the surrounding trees, together with siamang behaviours, supported selection based on predation risk and access requirements; (2) the preferences of a solitary siamang were similar to those of a family group; and (3) sleeping site locations within home ranges were indicative of home range defence, scramble competition with other groups or other species, or food requirements. Our data showed that (1) sleeping trees were tall, emergent trees with some, albeit low, connectivity to the neighbouring canopy, and that they were surrounded by other tall trees. Siamangs showed early entry into and departure from sleeping trees, and slept at the ends of branches. These results indicate that the siamangs’ choice of sleeping trees and related behaviours were strongly driven by predator avoidance. The observed regular reuse of sleeping sites, however, did not support anti-predation theory. (2) The solitary female displayed selection criteria for sleeping trees that were similar to those of the family group, but she slept more frequently in smaller trees than the latter. (3) Siamangs selected sleeping trees to avoid neighbouring groups, monopolise resources (competition), and to be near their last feeding tree. Our findings indicate selectivity in the siamangs’ use of sleeping trees, with only a few trees in the study site being used for this purpose. Any reduction in the availability of such trees might make otherwise suitable habitat unsuitable for these highly arboreal small apes.
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: Scopus
Sleeping trees and sleep-related behaviours of the siamang (Symphalangus syndactylus) in a tropical lowland rainforest, Sumatra, Indonesia.
Authors: Harrison, N.J., Hill, R.A., Alexander, C., Marsh, C.D., Nowak, M.G., Abdullah, A., Slater, H.D. and Korstjens, A.H.
Pages: 63-75
DOI: 10.1007/s10329-020-00849-8
Abstract:Sleeping tree selection and related behaviours of a family group and a solitary female siamang (Symphalangus syndactylus) were investigated over a 5-month period in northern Sumatra, Indonesia. We performed all day follows, sleeping tree surveys and forest plot enumerations in the field. We tested whether: (1) physical characteristics of sleeping trees and the surrounding trees, together with siamang behaviours, supported selection based on predation risk and access requirements; (2) the preferences of a solitary siamang were similar to those of a family group; and (3) sleeping site locations within home ranges were indicative of home range defence, scramble competition with other groups or other species, or food requirements. Our data showed that (1) sleeping trees were tall, emergent trees with some, albeit low, connectivity to the neighbouring canopy, and that they were surrounded by other tall trees. Siamangs showed early entry into and departure from sleeping trees, and slept at the ends of branches. These results indicate that the siamangs' choice of sleeping trees and related behaviours were strongly driven by predator avoidance. The observed regular reuse of sleeping sites, however, did not support anti-predation theory. (2) The solitary female displayed selection criteria for sleeping trees that were similar to those of the family group, but she slept more frequently in smaller trees than the latter. (3) Siamangs selected sleeping trees to avoid neighbouring groups, monopolise resources (competition), and to be near their last feeding tree. Our findings indicate selectivity in the siamangs' use of sleeping trees, with only a few trees in the study site being used for this purpose. Any reduction in the availability of such trees might make otherwise suitable habitat unsuitable for these highly arboreal small apes.
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: PubMed
Sleeping trees and sleep-related behaviours of the siamang (<i>Symphalangus syndactylus</i>) in a tropical lowland rainforest, Sumatra, Indonesia
Authors: Harrison, N.J., Hill, R.A., Alexander, C., Marsh, C.D., Nowak, M.G., Abdullah, A., Slater, H.D. and Korstjens, A.H.
Pages: 63-75
DOI: 10.1007/s10329-020-00849-8
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: Web of Science (Lite)
Sleeping trees and sleep-related behaviours of siamang (Symphalangus syndactylus) living in a degraded lowland forest, Sumatra, Indonesia.
Authors: Bowden, M. and Harrison, N.
Conference: Bournemouth University, Faculty of Science and Technology
Abstract:Tropical forests are hotspots for biodiversity and hold some of the world’s most unique flora and fauna, but anthropogenic pressures are causing large-scale tropical forest disruption and clearance. Southeast Asia is experiencing the highest rate of change, altering forest composition with intensive selective and mechanical logging practices. The loss of the tallest trees within primate habitat may negatively affect arboreal primates that spend the majority of their lives high in the canopy. Some primate species can spend up to 50% of their time at sleeping sites and must therefore select the most appropriate tree sites to sleep in. The behavioural ecology and conservation of primates are generally well documented, but small apes have gained far less attention compared to great ape species. In this study, sleeping tree selection of siamang (Symphalangus syndactylus) were investigated from April to August 2018 at the Sikundur Monitoring Post, a degraded lowland forest in Gunung Leuser National Park, Sumatra, Indonesia. Siamang were shown to sleep at the end of branches in tall, stable, emergent trees, high above the mean canopy height. Sleeping trees had an optimum percentage of canopy connectivity and number of large branches, as well as being surrounded by taller trees. Siamang entered sleeping trees before sunset and left before sunrise. All these factors suggest that antipredation is an important factor affecting sleeping behaviour. However, siamang in this study had regular sleeping trees, a quality so far undocumented amongst other hylobatids. This re-use of the same sleeping trees goes against the idea that predation is the main driver of sleeping site selection, as regularly used sleeping sites are more predictable to predators. Sleeping tree re-use may be explained by the degraded nature of the Sikundur forest or could be an adaptation of the siamang’s unique distribution, morphology and behaviour. Siamang did not position their sleeping trees close to fruiting trees but instead may select trees on a basis of comfort and stability. By understanding siamang sleeping sites in greater depth, conservation management plans will be able to mitigate the loss of an already endangered primate species.
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: Manual
Sleeping trees and sleep-related behaviours of the siamang (Symphalangus syndactylus) in a tropical lowland rainforest, Sumatra, Indonesia.
Authors: Harrison, N.J., Hill, R.A., Alexander, C., Marsh, C.D., Nowak, M.G., Abdullah, A., Slater, H.D. and Korstjens, A.H.
Pages: 63-75
DOI: 10.1007/s10329-020-00849-8
Abstract:Sleeping tree selection and related behaviours of a family group and a solitary female siamang (Symphalangus syndactylus) were investigated over a 5-month period in northern Sumatra, Indonesia. We performed all day follows, sleeping tree surveys and forest plot enumerations in the field. We tested whether: (1) physical characteristics of sleeping trees and the surrounding trees, together with siamang behaviours, supported selection based on predation risk and access requirements; (2) the preferences of a solitary siamang were similar to those of a family group; and (3) sleeping site locations within home ranges were indicative of home range defence, scramble competition with other groups or other species, or food requirements. Our data showed that (1) sleeping trees were tall, emergent trees with some, albeit low, connectivity to the neighbouring canopy, and that they were surrounded by other tall trees. Siamangs showed early entry into and departure from sleeping trees, and slept at the ends of branches. These results indicate that the siamangs' choice of sleeping trees and related behaviours were strongly driven by predator avoidance. The observed regular reuse of sleeping sites, however, did not support anti-predation theory. (2) The solitary female displayed selection criteria for sleeping trees that were similar to those of the family group, but she slept more frequently in smaller trees than the latter. (3) Siamangs selected sleeping trees to avoid neighbouring groups, monopolise resources (competition), and to be near their last feeding tree. Our findings indicate selectivity in the siamangs' use of sleeping trees, with only a few trees in the study site being used for this purpose. Any reduction in the availability of such trees might make otherwise suitable habitat unsuitable for these highly arboreal small apes.
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: Europe PubMed Central
Sleeping trees and sleep-related behaviours of the siamang (Symphalangus syndactylus) in a tropical lowland rainforest, Sumatra, Indonesia
Authors: Harrison, N.J., Hill, R.A., Alexander, C., Marsh, C.D., Nowak, M.G., Abdullah, A., Slater, H.D. and Korstjens, A.H.
Pages: 63-75
Abstract:Sleeping tree selection and related behaviours of a family group and a solitary female siamang (Symphalangus syndactylus) were investigated over a 5-month period in northern Sumatra, Indonesia. We performed all day follows, sleeping tree surveys and forest plot enumerations in the field. We tested whether: (1) physical characteristics of sleeping trees and the surrounding trees, together with siamang behaviours, supported selection based on predation risk and access requirements; (2) the preferences of a solitary siamang were similar to those of a family group; and (3) sleeping site locations within home ranges were indicative of home range defence, scramble competition with other groups or other species, or food requirements. Our data showed that (1) sleeping trees were tall, emergent trees with some, albeit low, connectivity to the neighbouring canopy, and that they were surrounded by other tall trees. Siamangs showed early entry into and departure from sleeping trees, and slept at the ends of branches. These results indicate that the siamangs’ choice of sleeping trees and related behaviours were strongly driven by predator avoidance. The observed regular reuse of sleeping sites, however, did not support anti-predation theory. (2) The solitary female displayed selection criteria for sleeping trees that were similar to those of the family group, but she slept more frequently in smaller trees than the latter. (3) Siamangs selected sleeping trees to avoid neighbouring groups, monopolise resources (competition), and to be near their last feeding tree. Our findings indicate selectivity in the siamangs’ use of sleeping trees, with only a few trees in the study site being used for this purpose. Any reduction in the availability of such trees might make otherwise suitable habitat unsuitable for these highly arboreal small apes.
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: BURO EPrints
Sleeping trees and sleep-related behaviours of siamang (Symphalangus syndactylus) living in a degraded lowland forest, Sumatra, Indonesia.
Authors: Harrison, N.J.
Conference: Bournemouth University
Pages: ?-? (101)
Abstract:Tropical forests are hotspots for biodiversity and hold some of the world’s most unique flora and fauna, but anthropogenic pressures are causing large-scale tropical forest disruption and clearance. Southeast Asia is experiencing the highest rate of change, altering forest composition with intensive selective and mechanical logging practices. The loss of the tallest trees within primate habitat may negatively affect arboreal primates that spend the majority of their lives high in the canopy. Some primate species can spend up to 50% of their time at sleeping sites and must therefore select the most appropriate tree sites to sleep in. The behavioural ecology and conservation of primates are generally well documented, but small apes have gained far less attention compared to great ape species. In this study, sleeping tree selection of siamang (Symphalangus syndactylus) were investigated from April to August 2018 at the Sikundur Monitoring Post, a degraded lowland forest in Gunung Leuser National Park, Sumatra, Indonesia. Siamang were shown to sleep at the end of branches in tall, stable, emergent trees, high above the mean canopy height. Sleeping trees had an optimum percentage of canopy connectivity and number of large branches, as well as being surrounded by taller trees. Siamang entered sleeping trees before sunset and left before sunrise. All these factors suggest that antipredation is an important factor affecting sleeping behaviour. However, siamang in this study had regular sleeping trees, a quality so far undocumented amongst other hylobatids. This re-use of the same sleeping trees goes against the idea that predation is the main driver of sleeping site selection, as regularly used sleeping sites are more predictable to predators. Sleeping tree re-use may be explained by the degraded nature of the Sikundur forest or could be an adaptation of the siamang’s unique distribution, morphology and behaviour. Siamang did not position their sleeping trees close to fruiting trees but instead may select trees on a basis of comfort and stability. By understanding siamang sleeping sites in greater depth, conservation management plans will be able to mitigate the loss of an already endangered primate species.
https://eprints.bournemouth.ac.uk/32398/
https://eprints.bournemouth.ac.uk/34357/
Source: BURO EPrints