Resource selection by tropical frugivorous birds: integrating multiple interactions

Area of Science:

• Ecology
• Behavioral Ecology
• Quantitative Ecology

Background:

• Resource selection by organisms is influenced by resource traits, organism traits, and ecological interactions like competition and predation.
• Understanding these factors is crucial for predicting species distribution and community dynamics.

Purpose of the Study:

• To develop a quantitative model integrating resource and organism characteristics with ecological interactions to predict resource profitability.
• To apply this model to predict fruit selection by tropical birds, demonstrating its broader applicability.

Main Methods:

• Developed a quantitative model defining fruit profitability as a function of rewards (mass, calories) and costs (handling, search, interference, predation).
• Incorporated species-specific differences in body and bill size affecting handling time.
• Integrated ecological interactions such as behavioral interference, exploitation competition, and predation risk.

Main Results:

• Fruit profitability increases with size up to a point where handling time costs offset mass rewards.
• Fruit size at optimal profitability varies with consumer body and bill size.
• Decreasing fruit availability and increasing search time reduce profitability, especially for larger consumers and smaller fruits.
• Ecological interactions can alter the profitability hierarchy of resources.

Conclusions:

• The developed model accurately predicts resource selection by integrating resource-organism traits and ecological interactions.
• The model's predictions are supported by existing ecological studies, highlighting its utility for diverse systems.
• This framework advances our understanding of foraging behavior and ecological dynamics.