Intraspecific Variation in Crayfish Behaviour Alters Stream Ecosystem Functions
Bana A Kabalan1, Alexander J Reisinger2, Lauren M Pintor3
1School of Forest, Fisheries and Geomatics Sciences, University of Florida, Gainesville, Florida, USA.
Ecology Letters
|June 6, 2025
Summary
Animal behavior changes due to human impact affect stream ecosystems. Crayfish movement and boldness influence metabolism, nutrient cycling, and leaf litter breakdown, showing the importance of within-species variation.
Area of Science:
- Ecology
- Behavioral Ecology
- Freshwater Ecology
Background:
- Human-induced environmental changes are altering animal behavior.
- The ecological consequences of these behavioral shifts are not well understood.
- Intraspecific variation in behavior is often overlooked in ecological studies.
Purpose of the Study:
- To investigate how among-population variation in behavioral traits of freshwater crayfish affects stream ecosystem functions.
- To determine the ecological impacts of crayfish movement and boldness.
- To highlight the importance of intraspecific variation in ecological frameworks.
Main Methods:
- Field studies in natural streams and controlled mesocosm experiments.
- Quantification of crayfish movement behavior and boldness.
- Measurement of ecosystem functions including water column metabolism and leaf litter breakdown.
Main Results:
- Crayfish movement behavior significantly increased water column metabolism in both natural and experimental settings.
- Movement behavior influenced nutrient cycling through bioturbation.
- Boldness in crayfish negatively affected leaf litter breakdown rates.
- Within-species behavioral differences had a greater impact on ecosystem functions than species identity.
Conclusions:
- Shifts in animal movement behavior can drive fundamental ecological processes in streams.
- Intraspecific behavioral variation plays a crucial role in ecosystem functioning.
- Ecological frameworks should incorporate the significance of within-species trait variation for a comprehensive understanding of ecosystem dynamics.
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