Associational effects need to be studied within an optimal foraging framework

Area of Science:

• Ecology
• Zoology
• Botany

Background:

• Plant-herbivore interactions are central to ecology, with a key question being resource selection by herbivores.
• The theory of optimal foraging offers a mathematical framework for understanding animal resource selection under constraints.
• Associational effects, which describe how plant community characteristics influence herbivory patterns, have yielded variable results, suggesting a need for alternative explanations.

Purpose of the Study:

• To bridge the gap between optimal foraging theory and associational effects research in plant-herbivore interactions.
• To evaluate whether proposed mechanisms for associational effects can be explained by optimal foraging.
• To provide guidance for future studies to differentiate between optimal foraging and other mechanisms driving associational effects.

Main Methods:

• Reviewing existing literature on associational effects and optimal foraging theory.
• Analyzing studies, primarily with mammalian herbivores and invertebrates, that integrate optimal foraging frameworks.
• Evaluating proposed mechanisms for associational effects in the context of herbivore foraging choices.

Main Results:

• Associational effects studies often overlook herbivores' active foraging choices, such as plant size.
• Optimal foraging theory provides a potential explanation for the variability and idiosyncrasy observed in associational effects.
• Integrating optimal foraging principles can enhance the understanding of plant-herbivore interactions and associational effects.

Conclusions:

• Optimal foraging theory offers a unifying framework for understanding plant-herbivore interactions and associational effects.
• Considering herbivores as active agents in these interactions links to broader ecological fields like nutritional and landscape ecology.
• This integrated approach has significant implications for conservation and wildlife management practices.