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Evaluating the effects of trophic complexity on a keystone predator by disassembling a partial intraguild predation
Jon M Davenport1, David R Chalcraft
1Department of Biology and North Carolina Center for Biodiversity, East Carolina University, Greenville, NC 27858, USA. jondavenport80@gmail.com
The Journal of Animal Ecology
|September 29, 2011
Summary
Food web complexity impacts intermediate predator performance. Simplifying food webs affected salamander growth, with effects depending on prey availability and predator removal. This highlights complex trophic interactions in pond ecosystems.
Area of Science:
- Ecology
- Aquatic Ecology
- Food Web Dynamics
Background:
- Trophic complexity influences species performance, but its effects on intermediate predators are not fully understood.
- Larval Ambystoma opacum, an intermediate predator in pond food webs, can act as a keystone species.
- A. opacum inhabits food webs with varying trophic complexity, including simpler systems.
Purpose of the Study:
- To investigate how simplifying a partial intraguild predation (IGP) food web affects the growth and survival of larval A. opacum.
- To determine the impact of removing top predators and shared prey on A. opacum performance under different prey abundances.
Main Methods:
- Experimental simplification of a partial IGP pond food web.
- Manipulation of top predator and shared prey abundance.
- Measurement of larval A. opacum growth and survival rates.
Main Results:
- Removing top predators consistently increased A. opacum survival.
- Food web simplification affected A. opacum growth only when prey was abundant, with non-additive effects observed.
- Top predators benefited A. opacum by reducing intraspecific competition.
Conclusions:
- The impact of food web simplification on intermediate predator performance is complex and context-dependent.
- Prey abundance and the specific method of food web simplification significantly influence A. opacum growth and survival.
- Trophic complexity generates variation in the performance of key intermediate predators in temporary pond ecosystems.
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