A bird's-eye view on turbulence: seabird foraging associations with evolving surface flow features

Area of Science:

• Marine ecology
• Animal behavior
• Fluid dynamics

Background:

• Seabird foraging is crucial for predicting responses to coastal change.
• Turbulence from structures can impact foraging in tidal seas, but small-scale features are hard to observe.
• Understanding these cues is vital for volatile predators like seabirds.

Purpose of the Study:

• To investigate if localized turbulence features act as physical foraging cues for seabirds.
• To quantify the relationship between turbulence and seabird foraging behavior using drone technology.

Main Methods:

• Synchronized drone-based tracking of surface-foraging terns (143 trajectories, 3 species) and turbulent surface flow features.
• Incorporation of vorticity and upwelling data into a hidden Markov model.

Main Results:

• First evidence that localized turbulence features provide physical foraging cues for seabirds.
• Terns showed increased active foraging with stronger vorticity.
• Upwelling features ahead of flight paths prompted transit behavior.

Conclusions:

• Turbulence features are significant localized foraging cues for seabirds.
• This drone-based quantitative approach bridges knowledge gaps in seabird sensory and foraging ecology.
• Findings inform predictions of seabird responses to coastal change and sustainable ocean development.