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Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter
Published on: March 12, 2013
A non-trophic interaction chain links predators in different spatial niches
Renée P Prasad1, William E Snyder
1Department of Entomology, Washington State University, Pullman, WA 99164-6382, USA.
Oecologia
|October 31, 2009
Summary
Non-trophic interactions, where species alter others' behavior without changing their numbers, are common. This study shows how aphid behavior, triggered by lady beetles, influences ground predator prey-switching, linking distant species.
Area of Science:
- Ecology
- Behavioral Ecology
- Community Ecology
Background:
- Non-trophic interactions, affecting behavior without altering density, are widespread but understudied in diverse communities.
- Ecological communities feature complex interactions beyond direct consumption.
Purpose of the Study:
- To investigate cascading non-trophic interactions in a species-rich community.
- To explore how behavioral changes in one species can influence interactions between other, spatially separated species.
Main Methods:
- Field and greenhouse experiments were conducted.
- Two predator-prey systems were examined: ground beetles/fly eggs and lady beetles/aphids.
- Observed behavioral responses of prey and predator switching were recorded.
Main Results:
- Ground predators consumed fly eggs unless aphids and lady beetles were present.
- Aphids dropped from foliage to escape lady beetles, attracting ground predators.
- Ground predators switched prey from fly eggs to aphids, demonstrating a non-trophic cascade.
Conclusions:
- Non-trophic interactions can propagate through food chains involving more than three species.
- Behaviorally mediated interactions can link species that are spatially isolated.
- Antipredator behavior can initiate indirect ecological effects across different habitats.
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