Logo image
Using population monitoring programs to detect changes in mammalian communities
Journal article   Peer reviewed

Using population monitoring programs to detect changes in mammalian communities

Vratika Chaudhary, Varun R. Goswami, Gavin Jones, Kok Ben Toh, Tana Tapi, Chandan Ri, Marc Kéry and Madan K. Oli
Biological conservation, Vol.276, p.109778
12/2022
DOI: 10.1016/j.biocon.2022.109778

View Online

Abstract

The global biodiversity crisis is escalating rapidly, with nearly a million species facing extinction risk in the near future. Monitoring of Essential Biodiversity Variables (EBV; key variables measured to detect changes in biodiversity) over time is important for biodiversity conservation, which in turn necessitates baseline estimates of EBVs. Using camera-trap data for six years (2013–2018) and a Bayesian multispecies occupancy model, we estimated species richness and species-specific occupancy of a mammalian community in Pakke Tiger Reserve, India. We detected 28 species of mammals in our camera traps. The model-based estimate of species richness during the study period was 41 (95 % CRI: 39–42) species, with no evidence of any substantial temporal variation. We found that carnivore and herbivore species richness was higher in greener habitats and that omnivore species richness was higher at lower-elevation sites. Annual average species occupancy probability (at the scale of 4-km2 sampling units) did not vary substantially between years but was lowest in 2014 (0.54, 95 % CRI: 0.20–0.84) and highest in 2013 (0.59, 95 % CRI: 0.27–0.87). Mean species-specific occupancy averaged across the years varied substantially among species, ranging from a low of 0.03 (95 % CRI: 0.00–0.08) for the masked palm civet Paguma larvata to a high of 0.94 (95 % CRI: 0.87–0.98) for the Asian elephant Elephas maximus. Mean occupancy probability was highest for herbivores followed by omnivores and carnivores. Species-specific detection probability (for a 30–60-day survey period) was not influenced by survey effort but increased with body mass for carnivores and decreased with body mass for herbivores and omnivores. We propose a framework for efficient monitoring of species and community-level EBV, utilizing data collected during the monitoring of high-profile species of conservation concern, such as tigers Panthera tigris in India.
Community dynamics Essential biodiversity variables (EBV) Hierarchical models Imperfect detection Multi-species occupancy models (MSOM) Northeast India Species richness

Details

Logo image