Cold stunning or hypothermic stunning occurs in reptiles when they are exposed to cold water for prolonged periods of time. Since they are cold blooded – meaning that their body temperature matches the external temperature – if the temperature drops below 53.6 degrees Fahrenheit or 12 degrees Celsius, they become weak and inactive. This prevents them from migrating to warmer waters and prevents them from feeding. A cold stunned sea turtle will either be found floating on the surface of the ocean or on the beach. If no human intervention occurs, the sea turtles usually pass away from hypothermia, boat strikes or from their bodies shutting down among a number of other complications.
Cold stunning is considered to be a phenomenon that has been documented as early as 1970. While it occurs in several locations all around the world, here is how these 3 US based locations help to save, rehabilitate and return cold stunned sea turtles back into the wild:
In the wide flat seagrass of the St. Joseph Bay located on the Gulf Coast of Florida panhandle, green sea turtles are found cold stunned here quite often. The sea grass is a food source for the sea turtles and since it is in shallow water, the temperature can change very quickly. in January of 2018, over 1,000 mainly juvenile green sea turtles were rescued in the St. Joseph Bay. By comparison, in 2010 over 4,500 sea turtles were rescued within the state of Florida due to cold stunning. The Florida Fish and Wildlife Commission leads the response and then several non-profit organizations along with local aquariums and marine mammal facilities work together in order to rehabilitate and release these sea turtles.
On average about 600 cold stunned sea turtles are rescued, rehabilitated and released along the Cape Cod Coast. During the winter of 2014 through 2015, 1,243 cold stunned sea turtles washed up onto the Cape beaches. Fortunately, 746 were still alive when discovered. The Mass Audubon’s Wellfleet Bay Wildlife Sanctuary lead the response efforts. The New England Aquarium’s Animal Care Center in Quincy assessed the sea turtles and treated them. As their facility filled up with cold stunned victims needing treatment, additional patients were transferred to multiple other facilities throughout the east and gulf coasts. Here is an excellently documented 4 part series by the New England Aquarium of how it all works:
Although cold stunned sea turtles are found and retrieved throughout the entire coast of Texas, The majority of turtles are typically found in the Upper Laguna Madre and Corpus Christi Bay. During the winter of 2017 through 2018, the largest cold stunning event ever in Texas was recorded with over 3,500 sea turtles – primarily juvenile green turtles – needing assistance. The National Park Service leads the response efforts and then the local non-profit organizations and local aquariums come in to rehab and release.
So how do these facilities treat a cold stunned sea turtle so that they can be released back into the wild? Once a cold stunned sea turtle is found – either by boat patrol or on foot surveying the beach looking for time – they are transported to a hold facility. They are placed into a dry tub or a banana box and given a proper health check. They are then slowly warmed up until their body temperature reaches an acceptable degree. From there they will be placed into a tank with water and closely monitored and fed by the facilities staff so that they can regain their strength. Once they are fully recovered they are tagged and released.
Since the 90s we have seen an increase in the sea turtle populations all over the world due to these efforts among ongoing efforts throughout the year.