Disentangling prey-handling efficiency of larval newts through multivariate prey trait analysis

Abstract

Multivariate prey trait analysis is a functional approach to understand predator–prey relationships. In the present study, six prey macroinvertebrate ecological traits were used to identify several key factors in the handling efficiency of seven predatory larval newt species. The results revealed a remarkable similarity in the feeding behaviour among species, suggesting a foraging behaviour convergence among species in the prey-handling efficiency of larval newts. Nevertheless, larvae of some newt species showed clear preferences for particular categories of ecological trait; for example, Lissotriton vulgaris tended to feed on macroinvertebrate taxa with random trajectory, and Calotriton asper fed on macroinvertebrate taxa with high agility. In contrast, Mesotriton alpestris showed a clear ability to feed on prey with movable accessories (cases/tubes) and patterned concealment. This study shows how multivariate approaches can complement traditional diet analyses, and the method has wide applicability across life-stages and species.

Keywords:

• feeding behaviour
• multivariate approach
• fuzzy principal component analysis
• ADE-4
• Amphibia

Acknowledgements

The author would like to thank the Spanish Employment Agency (INEM) for its funding support. Dr Elina Halttunen is acknowledged for valuable comments and corrections on the manuscript. I also appreciate the constructive comments on the manuscript given by Dr Antonio Romano and two other anonymous referees.