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Published on: August 8, 2017
Energy availability and density estimates in African ungulates.
Nathalie Pettorelli1, Jakob Bro-Jørgensen, Sarah M Durant
1Zoological Society of London, Institute of Zoology, Regent's Park, London NW1 4RY, United Kingdom. nathalie.pettorelli@ioz.ac.uk
The American Naturalist
|March 24, 2009
Summary
Primary productivity generally supports higher African ungulate abundance. Satellite data revealed this link, though species-specific variations and survey area influence the relationship, offering insights for conservation.
Area of Science:
- Ecology
- Remote Sensing
- Conservation Biology
Background:
- The relationship between primary productivity and species richness is well-studied.
- However, the connection between primary productivity and species abundance remains less understood, particularly for large mammals.
Purpose of the Study:
- To investigate how primary productivity influences the density of African ungulate populations.
- To assess the utility of satellite-derived vegetation indices in understanding these ecological relationships.
Main Methods:
- Utilized satellite-based Normalized Difference Vegetation Index (NDVI) to estimate primary productivity across various African landscapes.
- Collected density estimates for 13 African ungulate species.
- Analyzed the correlation between NDVI and ungulate density, considering survey area size.
Main Results:
- A general positive correlation was observed between primary productivity and ungulate density estimates.
- The strength of this relationship varied significantly among different ungulate species.
- Accounting for the surveyed area was crucial for accurately depicting the functional relationship between productivity and abundance.
Conclusions:
- Primary productivity is a significant driver of African ungulate abundance.
- Remote sensing offers a valuable tool for assessing population dynamics in response to environmental changes.
- Future conservation efforts should consider the interplay between vegetation productivity and ungulate population health.
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