Understanding Leatherback Turtles Through Satellite and Acoustic Tags
Satellite tags provide valuable insights into the near real-time location data of leatherback turtles. Though, their high cost (over $3,500 per tag) and limited lifespan of 7-9 months make them less accessible for research purposes. In contrast, acoustic tags are more affordable (around $500 per tag) and can last for years.These tags emit an acoustic signal that is picked up by receivers placed in the ocean when the turtle passes within a range of 800-1200 meters (2,600-3,900 feet) in clear conditions. The collected data is then uploaded to networks like the Ocean Tracking Network.
Derek Aoki from Upwell explains the difference between working with satellite and acoustic data: “Being able to track our turtles’ daily movements through satellite data and observe their diving behavior is truly remarkable. Working with acoustic telemetry is a different experience as we receive detections in batches rather than daily updates. However, these detections are more precise than satellite ones, allowing us to pinpoint exact locations in relation to shipping channels, inlets, and other areas where human interactions may be high.”
In 2019,Upwell tagged eight leatherbacks with acoustic tags at Pacuare National Reserve in Costa rica. These turtles where detected in the Caribbean and along the eastern seaboard for up to 2.5 years.In the 2021-2023 nesting seasons,Derek deployed five acoustic tags provided by Upwell and an additional 10 tags from collaborators. He has been analyzing the data from these new tags along with the Pacuare tags, which has revealed potential areas where leatherbacks could interact with human activity.
One of DerekS findings is that leatherbacks have been detected in The Bureau of Ocean Energy Management’s (BOEM) wind lease areas and high-use shipping channels,as shown in the figure below. This suggests that turtles are present within these areas during migrations and/or foraging seasons.
This research has the potential to revolutionize our understanding of leatherback turtle behavior in the region.