Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale

Carvalho, JS; Meyer, Christoph FJ; Vicente, L; Marques, TA

Abstract

Conversion of forests to anthropogenic land‐uses increasingly subjects chimpanzee populations to
habitat changes and concomitant alterations in the plant resources available to them for nesting and
feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species
selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan
troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea‐Bissau, a forest‐savannah mosaic
widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine
support for the anti‐predator hypothesis. A zero‐altered generalized linear mixed model showed that
nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and
positively with the availability of smaller‐sized trees, reflecting characteristics of dense‐canopy forest. A
positive correlation between nest abundance and floristic richness (number of plant species) and
composition indicated that species‐rich open habitats are also important in nest site selection.
Restricting this analysis to feeding trees, nest abundance was again positively associated with the
availability of smaller‐sized trees, further supporting the preference for nesting in food tree species from
dense forest. Nest tree species selection was non‐random, and oil palms were used at a much lower
proportion (10%) than previously reported from other study sites in forest‐savannah mosaics. While this
study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better
quantitative data are needed to determine to what extent the construction of elevated nests is in fact a
response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our
findings can improve conservation decisions for the management of this important umbrella species as
well as its remaining suitable habitats.

Citation

Carvalho, J., Meyer, C. F., Vicente, L., & Marques, T. (2015). Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale. American Journal of Primatology, 77(2), 186-199. https://doi.org/10.1002/ajp.22321

• Journal Article Type: Article
• Acceptance Date: Jul 11, 2014
• Online Publication Date: Sep 15, 2014
• Publication Date: Feb 1, 2015
• Deposit Date: Jan 25, 2016
• Journal: American Journal of Primatology
• Print ISSN: 0275-2565
• Publisher: Wiley
• Volume: 77
• Issue: 2
• Pages: 186-199
• DOI: https://doi.org/10.1002/ajp.22321
• Publisher URL: http://dx.doi.org/10.1002/ajp.22321
• Related Public URLs: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1098-2345
• Additional Information: Funders : Fundação para a Ciência e Tecnologia;Conservation International; Grant Number: SFRH/BD/60702/2009