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Updated: May 24, 2026
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Recording Behavioral Responses to Reflection in Crayfish
Published on: May 14, 2010
Predatory functional response and prey choice identify predation differences between native/invasive and
Neal R Haddaway1, Ruth H Wilcox, Rachael E A Heptonstall
1School of Environment, Natural Resources and Geography, College of Natural Sciences, Bangor University, Bangor, United Kingdom.
Plos One
|February 24, 2012
Summary
Invasive signal crayfish have higher prey intake rates than native white-clawed crayfish. Parasitism further weakens native crayfish, contributing to their exclusion and reduced river biodiversity.
Area of Science:
- Ecology
- Invasive Species Biology
- Aquatic Ecology
Background:
- Invasive predators can disrupt native communities via predation and competition.
- The signal crayfish (Pacifastacus leniusculus) invasion threatens native white-clawed crayfish (Austropotamobius pallipes) in Europe.
Purpose of the Study:
- Compare predatory functional responses and prey selection between invasive and native crayfish.
- Assess the impact of parasitism on native crayfish predatory capabilities.
Main Methods:
- Quantified prey intake rates and handling times for both crayfish species.
- Analyzed prey choice (crustaceans, molluscs, bloodworm).
- Measured effects of Thelohania contejeani parasitism on native crayfish predation.
Main Results:
- Invasive crayfish exhibited higher prey intake rates and shorter handling times than native crayfish.
- Invasive crayfish were generalist predators, while natives showed prey selectivity.
- Parasitized native crayfish had significantly reduced prey intake, attack rates, and increased handling times.
Conclusions:
- Differences in functional responses contribute to invasive crayfish success and native species decline.
- Parasitism exacerbates native crayfish weakness, aiding their competitive exclusion and impacting ecosystem biodiversity.
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