During the heat of summer, many of us look forward to a refreshing swim in cooler water. However, if the water is too cold it becomes an unpleasant experience we can’t tolerate for long. Did you know that for sea turtles, cold water temperatures can also be fatal? Sudden cold snaps or intense, prolonged cold can be very dangerous for sea turtles, especially during the winter.
What is Cold Stunning?
Sea turtle are cold-blooded reptiles that depend on the temperature of their surroundings to maintain their body temperature. Sea turtles can normally control their body temperatures by moving between areas of water with different temperatures or basking in the sun at the water’s surface or on the beach. However, when temperatures rapidly decline and sea turtles are cut off from moving to warmer waters, they can suffer from a form of hypothermia we call cold stunning.
Cold stunning can be fatal as sea turtles become lethargic, experiencing decreased circulation and slowing of other body functions. Cold-stunned sea turtles are more likely to be hit by boats, eaten by predators, become sick, or die as their bodies shut down. Sea turtles are especially susceptible to cold stunning if water temperatures fall below 50 degrees Fahrenheit (10 degrees Celsius) or if they remain in shallow-water areas that can become very cold as air temperatures drop. This makes strong cold snaps and unseasonably cooler weather serious business for sea turtles.
Who Helps Cold-Stunned Sea Turtles?
NOAA and our partners monitor water temperatures and mount rescues of cold-stunned turtles as we are able. Rescued cold-stunned turtles are taken to partner facilities to recuperate and are released back to warmer waters. We see annual cold stunning events in three primary areas of the United States, though cold stunning also occurs in many other locations around the U.S. and the world.
Scientists triage cold stunned turtles inside, then place them in banana boxes for transport to rehabilitation facilities. Credit: NOAA.Massachusetts – In recent years, an average of 600 sea turtles have been found cold stunned along the Cape Cod Coast in Massachusetts from late October through December each year. In the winter of 2014-2015, 1243 sea turtles washed up on Cape beaches, of which 746 were alive. Local cold stunning response efforts are led by Mass Audubon’s Wellfleet Bay Wildlife Sanctuary.Cold-stunned sea turtles are loaded into a plane for transport from Massachusetts to rehabilitation facilities in the southern U.S. Credit: NOAA.
Rehabilitated cold-stunned sea turtles released by the Florida Aquarium in January 2018. Credit: NOAA.Cold-stunned green sea turtles recovering in holding tank at Texas State Aquarium. Credit: NOAA.
- Texas – Cold stunning occurs annually along the entire Texas coast. The majority of turtles are typically found in the Upper Laguna Madre and Corpus Christi Bay, which are excellent green turtle habitat.More than 3,500 sea turtles, primarily juvenile green turtles, were rescued between December 2017 and January 2018 in the largest cold stunning event ever recorded in Texas. The National Park Service leads response efforts to stranded and cold stunned sea turtles in Texas.
How Can I Help?
When the weather in your area gets chilly, or a strong cold front comes through, remember to:
- Keep an eye out for cold stunned sea turtles on beaches and shorelines
- Slow down if traveling by boat
- Report stranded or injured sea turtles to your local sea turtle stranding networks