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Spotting Cheetahs: Identifying Individuals by Their Footprints
Published on: May 1, 2016
Quantifying past and present connectivity illuminates a rapidly changing landscape for the African elephant
Clinton W Epps1, Samuel K Wasser, Jonah L Keim
1Department of Fisheries and Wildlife, Oregon State University, Nash Hall Room 104, Corvallis, OR, 97331, USA. Clinton.Epps@oregonstate.edu
Molecular Ecology
|February 13, 2013
Summary
Human settlement significantly impacts African elephant connectivity, shifting from historical landscape features like slope. Understanding these changes across time is crucial for effective conservation strategies.
Area of Science:
- Ecology
- Conservation Biology
- Population Genetics
Background:
- Land-use change poses challenges to quantifying population connectivity.
- Historical ecosystem data is often lacking, complicating conservation targets.
- Long-lived mega-herbivores are sensitive indicators of landscape changes.
Purpose of the Study:
- To contrast historical and contemporary connectivity of African elephants (Loxodonta africana).
- To determine factors influencing historical gene flow (landscape features vs. human settlement).
- To assess the impact of human settlement on contemporary connectivity and recent gene flow.
Main Methods:
- Utilized 16 microsatellite loci to estimate historical and recent gene flow in Tanzanian elephant populations.
- Modeled historical landscape resistance using gene flow data (FST, G'ST).
- Inferred contemporary landscape resistance from elephant resource selection via extensive walking surveys.
Main Results:
- Historical elephant connectivity was influenced by slope, not human settlement.
- Contemporary connectivity is primarily affected by human settlement.
- Recent gene flow reflects both slope influence and contemporary resistance.
Conclusions:
- Significant shifts in African elephant connectivity have occurred due to land-use change.
- Integrating multi-timescale inferences is vital for conservation in complex landscapes.
- Addresses the 'shifting baselines' problem in conservation planning.
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