Context-dependent, risk-sensitive foraging preferences in wild rufous hummingbirds

Area of Science:

• Behavioral Ecology
• Animal Behavior
• Ornithology

Background:

• Risk-sensitive foraging theory predicts how animals choose between food options with different reward levels and variabilities.
• Understanding foraging decisions is crucial for wildlife conservation and predicting species' responses to environmental changes.

Purpose of the Study:

• To investigate the risk-sensitive foraging preferences of wild rufous hummingbirds (Selasphorus rufus).
• To determine if hummingbirds' choices align with predictions of risk-sensitive foraging theory under different comparison contexts.

Main Methods:

• Presented wild rufous hummingbirds with artificial flowers offering sucrose rewards of constant, low-variance, and high-variance amounts.
• Conducted foraging trials using both trinary (three options) and binary (two options) comparisons.

Main Results:

• In trinary comparisons, hummingbirds preferred low-variance over constant, and constant over high-variance rewards.
• In binary comparisons, hummingbirds exhibited risk-averse behavior, preferring constant rewards over variable ones.
• Preference reversal occurred depending on the number of choices presented.

Conclusions:

• Hummingbird foraging preferences are context-dependent, influenced by the number of available options.
• Observed preference reversal challenges standard risk-sensitive foraging theory, suggesting other factors influence foraging choices.
• The study highlights the importance of local context in shaping animal foraging decisions.