Note from Our Naturalist
Sea Turtles in the Gulf of Maine
As we learned in the last quarter from a student report, sea turtles can be found in the Gulf of Maine, contrary to popular belief. The turtles we see are descendants from some of the oldest creatures on the planet, survivors of a mass extinction at the Triassic/Jurassic period boundary. (1.)
Four species are found in the Gulf of Maine, but only two are common visitors, the large Loggerhead, and the very much smaller Kemp's Ridley. These two turtles are coastal, feeding in shallow water for crabs and mollusks, like whelks and mussels. The rarely seen Green turtle also feeds in shallow water preferring a vegetarian diet, while the leatherback, largest of all sea turtles, feeds on jellies like sea nettle and lion's mane found in colder, more productive, deep ocean water.
All sea turtles migrate to warmer southerly waters to nest and cooler waters to feed. Hatchlings migrate offshore beginning an ocean stage, which may last up to 7 years. These juveniles usually feed and seek protection in the Sargasso Sea off the Southeastern US coast. Eventually, they find their way into the northward moving current of the Gulf Stream, feeding in the warm waters of late summer and autumn. They move south when the water temperature drops but enclosed bodies of water like Cape Cod Bay tend to draw them in. They can become “cold stunned” or shocked if they do not depart soon enough causing their activity to slow, and then cease, causing them to strand. If found, they are usually underweight and possibly suffering from severe injury and infection. Recovery programs, such as that run by Mass. Audubon in Wellfleet on Cape Cod can get turtles into rehabilitation facilities quickly where their health can be restored sufficiently to release them back into the wild. (2.)
All sea turtles in the US are protected by the Endangered Species Act (ESA). In Canada, Leatherbacks are protected by the Species at Risk Act (SARA), while Loggerheads are being considered for listing. The other two species do not occur in Canadian waters.
Sea turtles are at risk of injury from collisions, as they can be hard to see, and entanglement, in lobster buoys and fishing nets. Entangled turtles are particularly vulnerable and are best assisted by those trained to help. The National Marine Fisheries (US) maintains a hotline to report entanglements at 866-755-NOAA (6622). Stand by the animal if possible until assistance arrives or be able to provide a precise GPS location to the network. (3.)
1.Thurston, Harry 2011, The Atlantic Coast, Vancouver, BC Canada, Greystone Books
2. Prescott, Bob, 2015, Lecture to NOAA BWet Program, Wellfleet, Ma.
3. Stellwagen Bank National Marine Sanctuary 1993, Management Plan, stellwagen.noaa.gov.management.1993 plan
John Halloran is the Director of Science for GOMI and a member of the GOMI Guide Team. John’s interests focus on the ocean environment where he pursues educational adventure travel, research, and recreation by sail, paddle, and scuba.John is the founder and director of Adventure Learning, Newburyport, MA, which has been involved with educational outreach in area schools and recreational programs for teens and adults since 1980. A long-time educator, John was at the forefront of the experiential education movement in the U.S.For 36 years, he taught natural science in the Newburyport Public Schools. John has special interest and expertise in teacher training and standards for learning in math and science. His role has included direct teaching, teacher training, program development, grant writing, and developing partnerships with professionals in the field.