This blog post is a continuation of Ember the juvenile loggerhead’s heroic story. If you have not done so already, we suggest checking out our previous post, which covers Ember’s rescue and rehabilitation at the Georgia Sea Turtle Center and initial travel up the eastern seaboard. If you are all caught up, keep reading!

Ember has traveled approximately 1,941 km (1,206 miles) since our last update that ended on December 9th, 2022, when Ember was about 400 km (249 miles) off the coast of New Jersey. This brings the total distance covered since Ember’s release in Florida last October to a whopping 4,119 km (2,559 miles) in 78 days. To put it in perspective, that is equivalent to crossing the distance between New York City and San Francisco in two and a half months. What a tenacious little turtle!

As we described in our previous post, Ember’s long journey can be attributed to the movements of the Gulf Stream. The Gulf Stream is a strong ocean current that flows up the East Coast of the United States and Canada before crossing the Atlantic Ocean to Western Europe. It is part of the North Atlantic Gyre, one of five oceanic gyres (large circulatory systems made up of rotating currents) that keep the Earth’s oceans in constant movement. The Gulf Stream’s South Pacific relative, the East Australian Current, was featured in the movie Finding Nemo in a scene where fish friends Marlin and Dory catch a ride with Crush, a green sea turtle.

However, the Gulf Stream is not the tube-shaped roller-coaster “swirling vortex of terror” depicted in the movie. Think of it more as a giant river within the ocean, estimated to be between 50-100 km (31-62 miles) wide and reach depths of 1.5 km (1 mile) (Webb, n.d.). Its speed and temperature vary depending on location within the current, but it is warmest and fastest at the surface, which is where Ember is most likely to be spending time. In Upwell’s previous studies tracking juvenile loggerheads with diving sensors, preliminary results showed that they spend about 60% of their time underwater but only within the first 10 meters below the surface. Check out the animated map below showing Sea Surface Temperatures and you can see that up until December 15th, Ember was mostly in waters that are 4-7°C (7-12°F) warmer than the surrounding ocean.

However, from roughly December 21st to January 8th, Ember took a spin in colder waters outside of the Gulf Stream. Why might Ember have doubled back in the colder waters like that? The animation below helps to explain by showing Ember’s tracks overlaid on ocean currents. Can you see how the small black arrows showing the direction of the currents correlates with Ember’s changes in direction?

While Ember does run the risk of cold-stunning in the chillier waters outside the Gulf Stream, there are also benefits. Cold water often contains larger amounts of nutrients like plankton and algae that feed creatures like sea jellies and small shrimp which in turn feed juvenile turtles and many other species. Adult loggerheads will use their powerful jaws to eat hard-shelled prey like crabs, mollusks and shrimp, but until Ember is larger, the menu is more likely to include opportunistic meals like the ones mentioned above.

Unfortunately, Ember will most likely encounter plastic pollution mixed with the food that drifts in the current and eddies. Small bits of plastic and other trash can be confusing for a baby turtle learning what is tasty and what is toxic. The Gumbo Limbo Coastal Stewards (who helped release Ember) recently found 898 pieces of plastic in the stomach and intestines of a 1-month old turtle that washed up. Other threats that Ember may face include predators, like swordfish or bluefin tuna, or accidental capture by fisheries targeting these species.

Ember has not been deterred by threats, and on January 10th followed the current out into the colder waters of the North Atlantic. The micro-satellite tag attached to Ember’s carapace is estimated to have an 80-day lifespan (although some tags last longer) and to shed naturally as Ember grows. As of January 16th, Ember’s tag had been transmitting for 78 days. However, we are hopeful to receive further transmissions and  will continue sharing updates on Ember’s journey in our newsletters, so add your email to our mailing list to see where Ember goes next!

Sources, or, more fun things to read:

Webb, P. (n.d.). 9.2 The Gulf Stream – Introduction to Oceanography. Pressbooks. https://rwu.pressbooks.pub/webboceanography/chapter/9-2-the-gulf-stream/

What is an eddy? (n.d.). https://oceanservice.noaa.gov/facts/eddy.html

Woods Hole Oceanographic Institution. (n.d.). Currents, Gyres, & Eddies. https://www.whoi.edu/know-your-ocean/ocean-topics/how-the-ocean-works/ocean-circulation/currents-gyres-eddies/