Breeding Brown Pelicans Improve Foraging Performance as Energetic Needs Rise

Area of Science:

• Behavioral Ecology
• Wildlife Ecology
• Marine Biology

Background:

• Optimal foraging theory predicts animals maximize resource acquisition rates.
• Field studies on fine-scale foraging behavior shifts are limited, especially for species with mobile prey.
• Understanding these shifts is crucial for conservation in dynamic landscapes.

Purpose of the Study:

• To investigate changes in foraging behavior of breeding brown pelicans (Pelecanus occidentalis) over time.
• To relate pelican movements to foraging habitat quality using GPS telemetry and prey distribution models.
• To understand how energetic needs influence foraging strategies in response to resource availability.

Main Methods:

• GPS telemetry was used to track brown pelican movements.
• Distribution models of dominant prey species were employed.
• Pelican movements were correlated with changes in foraging habitat quality in the northern Gulf of Mexico.

Main Results:

• Pelican cohorts initially foraged in suboptimal habitats relative to prey availability.
• Foraging habitat quality significantly increased over the breeding season.
• This improvement in habitat quality outpaced general habitat trends at the study site.

Conclusions:

• Brown pelicans demonstrate adaptive foraging, adjusting patch use in response to increased energetic demands.
• These findings highlight the capacity of animal populations to optimize foraging in uncertain environments.
• Landscape features significantly impact foraging behavior and population dynamics.