Turtle Drifters

Turtle design (current)

The wooden turtle drifter was originally designed with “cold-stunned” sea turtles in mind. Each year as winter approaches many sea turtles in Cape Cod Bay, for example, begin to head south for warmer water, but end up being trapped. Before long they become stunned by the bay’s cold water, and their fate, whether that be washing ashore or leaving the bay to warmer waters, depends on Cape Cod Bay’s ocean currents, wind, and waves. The turtle drifter was designed to mimic cold-stunned turtles that are moved by these forces. As of July 2015, a few turtle drifters have been built and tested but there is much more to be learned about their water following behavior. Most of the instructions and dimensions below are approximations for an adult Loggerhead turtle but, with the help of James Melvin, a Falmouth Academy High School student in Nov 2015, we have also built and deployed at least one Kemp Ridley-sized turtle as shown in the pictures here.

Experimentation with design is still taking place to modify turtles to be self-righting. During the summer of 2015, Tim Anderson (West Washington State University) began a project to better understand the water following qualities of the turtle drifter. Bianca Santos (Virginia Institute of Marine Science) is also making more turtles in 2015 and fitting a loggerhead carcass with a transmitter.

While the turtle drifter is technically a surface drifter, the fact that a large portion of it protrudes from the water makes it’s path greatly wind and wave affected. With that said if you are interested in a drifter that more accurately follows ocean surface currents, the surface drifter may be a better option.

Part 1: Build

The turtle drifters are built with wood. [For detailed instructions, click here. – in development]

Part 2: Deploy

Turtle drifters are part of a project in Cape Cod so please contact us before deployment for optimal results.

Part 3: Track

All current month’s tracks are available at: https://www.nefsc.noaa.gov/drifter/drift_X.html.

A note on design

We keep the basic configuration/size the same in order to maintain the oceanographic-standard drag but try to use materials available at any hardware store. The idea is that the drifter can be built in any high school shop class, for example. It is a project in materials science. See our full list of models under the “Drifter History” tab. They all have a cross-sectional area of approximately one square meter and, since the electronic package is getting smaller, we have been able to further reduce the windage with each new design.