A Dynamic Foraging Habitat Distribution Estimate for Green Turtles in the Great Barrier Reef

Area of Science:

• Marine Ecology
• Conservation Biology
• Habitat Modeling

Background:

• Effective management of protected species requires detailed habitat use knowledge.
• Marine turtle foraging habitats can differ between human-impacted and pristine areas.

Purpose of the Study:

• To model habitat suitability for green turtles in the Great Barrier Reef.
• Identify environmental drivers of green turtle foraging in modified and unmodified sites.
• Map potential foraging areas at a regional scale.

Main Methods:

• Developed boosted regression tree habitat models using telemetry data (Fastloc GPS tracks).
• Utilized pseudo-absences (simulated correlated random walks) for model fitting.
• Assessed model performance using prediction accuracy, true skill statistic, deviance explained, and AUC.

Main Results:

• Shallow nearshore environments and midshelf reefs identified as key green turtle foraging areas.
• Predicted suitable habitats are influenced by factors like floods, development, and turbidity.
• Significant portions of suitable habitat overlap with Great Barrier Reef Marine Park zones.

Conclusions:

• Provides the first regional-scale foraging distribution map for green turtles.
• Biophysical drivers identified can aid habitat identification in data-limited regions.
• Habitat distribution changes offer insights into environmental and anthropogenic impacts on marine protected areas.