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Parasitism in a community context: trait-mediated interactions with competition and predation
Thomas R Raffel1, Jason T Hoverman, Neal T Halstead
1Department of Integrative Biology, University of South Florida, Tampa, Florida 33620, USA. traffel@cas.usf.edu
Ecology
|August 19, 2010
Summary
Parasitism, predation, and competition interact to affect tadpole development and survival. High tadpole density increases parasite infection by delaying development and prolonging exposure, highlighting host plasticity in parasite ecology.
Area of Science:
- Ecology
- Parasitology
- Evolutionary Biology
Background:
- Predation and competition influence species interactions and community stability.
- The interplay between these factors and parasitism is not well understood.
- Parasitic infections can significantly impact host populations.
Purpose of the Study:
- To investigate the combined effects of competition, predation, and parasitism on tadpole development and infection.
- To partition the effects of these interactions on tadpole exposure and susceptibility to Echinostoma trivolvis.
- To understand how host plasticity influences parasite dynamics.
Main Methods:
- Experimental manipulation of tadpole density (Bufo americanus).
- Introduction of a caged predator (Notophthalmus viridescens).
- Exposure to Echinostoma trivolvis trematodes in controlled mesocosms.
Main Results:
- Predation accelerated development and growth but did not affect parasite infection.
- Echinostoma trivolvis infection reduced survival and had opposite effects on development and activity.
- High tadpole density delayed development, increasing exposure duration and infection susceptibility, independent of immunomodulation.
Conclusions:
- Host density-dependent plasticity is a key factor in parasite transmission dynamics.
- Accounting for exposure duration and host susceptibility is crucial in parasite ecology.
- Interactions among predation, competition, and parasitism have complex effects on host populations.
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