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Niche width collapse in a resilient top predator following ecosystem fragmentation
Craig A Layman1, John P Quattrochi, Caroline M Peyer
1Marine Sciences Program, Department of Biological Sciences, Florida International University, 3000 NE 151st St, North Miami, FL 33181, USA. cal1634@yahoo.com
Ecology Letters
|September 12, 2007
Summary
Ecosystem fragmentation shrinks the trophic niche width of resilient top predators. This collapse, driven by reduced prey diversity, homogenizes food webs and increases extinction risk for these predators.
Area of Science:
- Ecology
- Conservation Biology
- Food Web Dynamics
Background:
- Ecosystem fragmentation impacts species survival and ecological roles.
- Shifts in top predator trophic roles can destabilize food webs and ecosystem function.
Purpose of the Study:
- To assess the effects of aquatic ecosystem fragmentation on the trophic ecology of a dominant top predator.
- To investigate how fragmentation influences trophic niche width and its relationship with prey diversity.
Main Methods:
- Utilized stable isotope ratios to quantify trophic niche width.
- Compared trophic niche width of a top predator in fragmented versus unimpacted aquatic ecosystems.
Main Results:
- Demonstrated a significant collapse in trophic niche width of the top predator in fragmented systems.
- Observed a strong correlation between reduced predator niche width and decreased diversity of available prey taxa.
- Identified a homogenization of energy flow pathways to top predators in fragmented environments.
Conclusions:
- Aquatic ecosystem fragmentation leads to a narrowed trophic niche for dominant predators.
- Homogenized energy flow and reduced prey availability destabilize food webs.
- Apparently resilient top predators in fragmented ecosystems face increased long-term extinction risk.
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