Biodiversity and Conservation

, Volume 23, Issue 11, pp 2669–2687 | Cite as

Western lowland gorilla density and nesting behavior in a Gabonese forest logged for 25 years: implications for gorilla conservation

  • Barbara Haurez
  • Charles-Albert Petre
  • Cédric Vermeulen
  • Nikki Tagg
  • Jean-Louis Doucet
Original Paper

Abstract

The tropical forests of the Congo Basin constitute biodiversity refuges that still hold large numbers of species, including endemic and endangered vertebrates. Along with several key species, the critically endangered western lowland gorilla (WLG) potentially contributes to forest dynamics through seed dispersal. Considering the extensive influence of timber harvesting on tropical forest ecosystems, the survival of gorilla populations in logged forests might prove critical for forest ecosystem conservation. We estimated WLG density, through a nest count survey, in a forest in southeast Gabon that has been logged for 25 years. Nesting behavior and habitat use were described and we applied generalized linear models to identify the factors that influence gorilla day and night habitat use. The estimated density of weaned gorillas, 1.5 gorillas km−2, is comparable with estimates from some protected areas and other sustainably managed sites within their range. Habitat type had the greatest influence on nest site distribution. We observed a preference for nesting in open terra firma forest, and open habitats in general, which supports the findings of previous studies. Habitat use during the day was strongly influenced by habitat type and human activities, and to a lesser degree by functional and non-functional roads, and rivers. Our results support the suggestion that logged forests are suitable habitats for WLG if hunting and poaching are controlled. We recommend collaborations between timber operators and scientists to improve the conservation potential of tropical forests and enhance the wildlife-management aspects of logging practices.

Keywords

Gorilla gorilla gorilla Nesting behavior Timber exploitation Long term impact Gabon Standing crop nest count 

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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  • Barbara Haurez
    • 1
    • 2
  • Charles-Albert Petre
    • 1
    • 3
    • 4
  • Cédric Vermeulen
    • 1
    • 2
  • Nikki Tagg
    • 3
  • Jean-Louis Doucet
    • 1
    • 2
  1. 1.Laboratory of Tropical and Subtropical Forestry, Unit of Forest and Nature Management, Gembloux Agro-Bio TechUniversity of LiègeGemblouxBelgium
  2. 2.École Régionale Post-Universitaire d’Aménagement et de Gestion Intégrés des Forêts et Territoires Tropicaux (ERAIFT)KinshasaDemocratic Republic of Congo
  3. 3.Projet Grands Singes (PGS) of the Centre for Research and ConservationRoyal Zoological Society of Antwerp (RZSA)AntwerpBelgium
  4. 4.Conservation Biology Unit, Section Education and NatureRoyal Belgian Institute of Natural SciencesBrusselsBelgium

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