Facing different predators: adaptiveness of behavioral and morphological traits under predation

Area of Science:

• Ecology
• Evolutionary Biology
• Behavioral Ecology

Background:

• Predation is a key factor structuring animal communities.
• Selective predation is often studied for single traits and predators, limiting comparative understanding.
• Phenotypic plasticity in prey species is crucial for survival but requires understanding differential predation pressures.

Purpose of the Study:

• To quantify and compare selective forces on behavioral and morphological traits of juvenile Eurasian perch (Perca fluviatilis).
• To assess and contrast the selective predation strategies of two common predators: adult perch and pike (Esox lucius).
• To investigate how different predators impose distinct selection pressures on prey traits.

Main Methods:

• Measurement of behavioral (e.g., vigilance, boldness) and morphological traits in juvenile Eurasian perch.
• Comparative analysis of selective values of these traits in response to adult perch and pike predation.
• Application of mixed-effects models and model averaging for robust data analysis.

Main Results:

• Selection pressures were stronger on behavioral traits than on morphological traits.
• Adult perch predators exhibited more selective predation than pike predators.
• Pike favored shallow-bodied, non-vigilant individuals, while perch predators selected for bolder, more active juvenile perch.

Conclusions:

• Different predators exert distinct selective pressures on juvenile perch, influencing trait evolution.
• Behavioral traits are more strongly selected than morphological traits in this predator-prey system.
• Findings provide insights into the phenotypic plasticity of juvenile perch in response to varied predation strategies.