Increasing land-use intensity reverses the relative occupancy of two quadrupedal scavengers

PLoS One. 2017 May 11;12(5):e0177143. doi: 10.1371/journal.pone.0177143. eCollection 2017.

Abstract

Human land use is continuously altering the natural environment, yet the greater ecological implications of this change for many groups that are key to healthy ecosystem functioning remains uncharacterised in the tropics. Terrestrial scavenging vertebrates are one such group, providing integral ecosystem services through the removal of carrion which is a crucial component of both nutrient cycling and disease dynamics. To explore how anthropogenic processes may affect forest scavengers, we investigated the changes in the relative occupancy of two important terrestrial scavengers along a gradient of land use intensity, ranging from protected forest to oil palm plantation in Borneo. We found the Malay civet (Viverra tangalunga) had highest, albeit variable, occupancy in areas of low land use intensity and the Southeast Asian water monitor (Varanus salvator macromaculatus) had highest occupancy in areas of high land use intensity. Land use had no effect on the combined occupancy of the two species. In high land use intensity sites, individual water monitors were larger and had better body condition, but at population level had a highly biased sex ratio with more males than females and increased signs of intraspecific conflict. We did not assess scavenging rate or efficiency as a process, but the high occupancy rates and apparent health of the scavengers in high land use intensity landscapes suggests this ecological process is robust to land use change.

MeSH terms

  • Animal Distribution / physiology*
  • Animals
  • Borneo
  • Ecology
  • Ecosystem*
  • Female
  • Forests
  • Lizards / physiology*
  • Male
  • Viverridae / physiology*

Grants and funding

Funding came from the Sime Darby Foundation, (http://www.yayasansimedarby.com) who provide financial support to the Sustainability of Altered Forest Ecosystems Project (SAFE). Sime Darby had no input into study design, data collection, analysis or preparation of manuscript. This work was also financially supported by the Sabah Foundation, Benta Wawasan, the Sabah Forestry Department and the South East Asia Rainforest Research Partnership. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.