By Hannah Glover
Happy World Sea Turtle Day!
I recently had a wonderful opportunity to help with a study on turtle behavior. I’m a graduate student at the University of Washington, but this summer I’m working abroad in Australia and New Zealand through the ASLO LOREX program. Debra Stokes, my host and advisor here, studies both coastal geology and ecology. I am a geologist by training, so it’s exciting to work with a researcher who crosses boundaries between fields to try to understand the ecosystem as a whole.
One of Deb’s new projects is focused on green turtle migration into and out of the Sandon River Estuary on Australia’s east coast. Most turtle research is focused on understanding nesting and hatching because it is important to protect them during their vulnerable breeding time. However, less is known about what these turtles do once they hatch! Sea turtles generally head out to the open ocean to eat and grow (like the ones in Finding Nemo), but Deb noticed that some turtles also commute daily in and out of Sandon River Estuary. They swim in during the last hours of light and head back out to the ocean in the early hours of the morning. Sometimes they have to fight against the tide on this daily commute
Currently, Deb is collecting data on how many turtles make this commute and whether their behavior changes between seasons. So, I got to help count turtles for two days at this at this beautiful estuary! Since these turtles are early-risers we watched beautiful sunrises and sunsets as we tracked their movement. We track turtles two different ways: counting the number of heads we see and collecting aerial drone videos. It’s exciting to try to spot turtle heads; they only come up for air for a few moments before diving again, so you have to keep your eyes on the water. We watch for long periods of time, but this method only counts the turtles that happen to come up for air. In contrast, the drones can only fly for 15-minutes but the videos capture all the passing turtles. The water is very clear and you can see the busy highway of commuting turtles. Both methods provide helpful data for understanding their movements. We still don’t know why they make this exhausting commute.
Usually I am more focused on the shape and evolution of estuaries. It was nice to take a research-vacation and think about the creatures who use these environments. I can’t wait to hear more about what Deb discovers.