Stranded Kemp's ridley turtle. Photo by Bill Allen, MassAudubon.

The recent cold snap and last weekend’s nor’easter have resulted in the first turtle stranding of the year.  This animal is currently in rehabilitation at the New England Aquarium.  Click here to read it’s story on the New England Aquarium’s Marine Animal Rescue Team Blog.

The Sea Turtle Stranding Network

MassAudubon staff rescuing a loggerhead turtle.

The National Marine Life Center is a partner in the National Sea Turtle Stranding and Salvage Network.  Within the Northeast Region, there are several other partners, each with slightly different responsibilities and all working collaboratively to help cold-stunned sea turtles.  The Massachusetts Audubon Society’s Wellfleet Bay Wildlife Sanctuary provides beach response and triage.  The New England Aquarium provides initial medical evaluation and critical care.  And the National Marine Life Center, along with the NOAA Woods Hole Science Aquarium, the University of New England’s Marine Animal Rehabilitation Center at Biddeford, Maine, and the Riverhead Foundation for Marine Research and Preservation in New York, provide on-going rehabilitative care.  The National Oceanic and Atmospheric Administration (“NOAA”) and the U.S. Fish and Wildlife Service oversee the stranding network.

Even with all these organizations working in partnership to help, in years with a lot of strandings there isn’t enough rehabilitation space.  When this happens, turtles are sent to Georgia, Florida, or sometimes farther for care.  That’s why we’re so excited to open the first two pools in the National Marine Life Center’s new marine animal rehabilitation hospital!  Each pool has room for up to 9 juvenile Kemp’s ridley turtles, the most common species and age class to strand on Cape Cod.  Or, each pool could fit up to 3 juvenile loggerhead turtles, the second most common to strand around here.  We’re pleased to reopen our doors to sea turtle patients this season.  And, as we raise additional funds, we will put additional pools on-line so we can help more animals.

What To Do If You Find A Stranded Sea Turtle

In the meantime, with turtle stranding season upon us, it’s a good time to remind people what to do if you find a stranded sea turtle in Massachusetts.

DON’T:
~ Don’t put the turtle back in the water.  It needs medical attention.
~ Don’t remove the turtle from the beach.  Special permits and training are required to work with these endangered animals.

DO:
~ Move the turtle above the high tide line.
~ Cover the turtle with dry seaweed, to help it from getting even colder.
~ Mark the turtle’s location with a stick, buoy, or other piece of beach debris so MassAudubon’s rescue volunteers can find it.
~ CALL MassAudubon’s Rescue Hotline at 508-349-2615.  Leave a message with very specific directions and include your contact number so they can call you back if they have questions.

If you live outside of Massachusetts, please click here to find the name of your state sea turtle stranding network coordinator.

Thanks for caring about stranded sea turtles!

A Kemp's ridley turtle in rehabilitation at NMLC.

The Leatherback

Photo credit: http://www.itsnature.org/sea/other/leatherback-turtle/

The leatherback is a “super turtle” in several aspects. First, as you may have guessed, it doesn’t have a hard shell like that of other sea turtles. Its shell is different – instead of having the ribs fuse and form a bony carapace (the top part of the shell), it has a layer of rubbery skin with a fibrous cartilage layer. This cartilage layer is covered again by membrane bone – called osteoderms. These are tiny bones about the size of a dime or quarter that lock together to form the carapace. This layer is a little flexible and this adaptation allows the leatherback to dive deeply into the water – depths of more than half a mile. It also swims faster, farther, and deeper than all other sea turtles, produces the heaviest and largest eggs, and yet is a gentle giant – eating primarily jellyfish.

One amazing thing about the leatherback is its cardiovascular system, which includes a countercurrent heat exchange system in its limbs. This system allows the leatherback to conserve body heat so that it can live in a wide range of habitats that other sea turtles cannot. The arteries and veins of the leatherback are formed in a tight network in its flippers. Arteries are the blood vessels that flow from the heart into the limbs, and veins flow from the limbs back to the heart.

As the warm blood from the arteries flows past the vein, they transfer heat to the veins before the veins lose their heat to the surface of the skin. With a counter current heat exchange system, the veins don’t carry cold blood back to the heart and lower the core body temperature – when the blood gets back to the lungs and heart it is warm. If the animal is too hot – the heat transfer can be reversed by transferring heat to the arteries so that the veins are cool when they flow back to the heart, thereby lowering the core body temperature.
They also control their body heat with thick layers of fat that surround the muscle. This works as excellent insulation in cold water. In warm water, they have a network of blood vessels that allows the blood to flow past the fat to the outer edges of the skin so that heat can be easily released. This is why nesting females’ throats turn pink.

A female leatherback dispelling heat via her pink throat. Photo credit: http://www.superstock.co.uk/stock-photos-images/1990-30657.

Another adaptation that leatherbacks and a few other sea turtles have is called esophageal papillae. These prongs are made of cartilage and line the throat of the turtle, and basically grip on to the jellyfish that it’s eating and ensures that it doesn’t slip back out as the turtle uses the muscles in its throat to expel excess salt water.

Leatherback showing esophageal papillae. Photo credit: http://museumvictoria.com.au/about/mv-blog/categories/melbourne-museum/.

The esophageal papillae also protect the leatherback from the stinging cells for the jellyfish – as you can imagine, the jellyfish don’t go down without a fight, so these cartilaginous prongs keep the turtle from being injured by its prey. Now, leatherbacks travel vast distances and require a lot of energy to make these migrations possible – but jellyfish are primarily water, a little protein, some vitamins and minerals, and some fat. So – how on earth can a leatherback fuel it’s body with them? Well, they actually have an extremely long esophagus that leads from the mouth to the rear of the body, and then it loops up the side again until it reaches the stomach, which is about a quarter of the way from the front of the turtle. This long esophagus acts as a holding pouch so that the leatherback can continually digest its food – as parts of its meal leaves the stomach digested, new jellyfish are being pushed into the stomach.

I’d like to mention just a couple more interesting things about the anatomy of the leatherback. The ends of leatherback bones contain cartilage laden with blood vessels. This is unique among sea turtles, and is thought to facilitate their rapid growth by allowing access to necessary nutrients.

The Loggerhead

Loggerhead sea turtle. Photo credit: http://scubaemporium.blogspot.com/2011/04/loggerhead-sea-turtles-compass-of-sea.html.

The loggerhead is the most abundant sea turtle in the United States. I love the loggerhead because it is the quintessential “awkward turtle.” They are slower than many other species of sea turtles, and that may be due to the fact that they are the most common turtle to be seen with epibiota on their shells. They are, of course, named the loggerhead because of their wide skull. Hatchling and juvenile loggerheads are pelagic – or live in the open ocean far from any coast. They like to hang out in convergence zones where they can get access to a variety of food sources. Loggerheads are a warm water species, and are rarely seen in water lower than 50ºF. Once they reach juvenile stage, loggerheads are take on a reddish-brown shell which is characteristic of the species and will stay with them throughout their lives.

Loggerheads prefer to eat mollusks and crustaceans, in order to do this their rhamphotheca (beak) is extremely thick, and they have broad, heavy muscles in their jaws for crushing.

Loggerhead feeding on a hermit crab. Photo credit: http://www.flickr.com/photos/belizediversity/2287668884/groups/.

As you may have guessed, loggerheads are completely carnivorous. They are opportunistic feeders. They eat mostly invertebrates and insects, but their diet can also include jellyfish, medusae, salps, barnacles, snails, aquirts, anemones, sea cucumbers, marine worms and fish.

Loggerheads reach sexual maturity at 17-33 years of age. Females lay an average of 110 eggs per clutch, with usually 2-3 nests per year, although they can lay up to 7. they wait about 2 weeks between nests. Their eggs will incubate in the nest for 50-75 days, depending on how warm the sand is. Like most sea turtles, females use an alternate gait on land, meaning they move the front left flipper at the same time as the back right, and vice versa. They are documented to have high nest fidelity.

Loggerhead leaving the sea to nest. Photo credit: http://www.scistp.org/lifehistory/cycle.php.

The Green

The green sea turtle is your “poster child” sea turtle, if you will. They are the most commonly recognized species because of their beauty. Surprisingly, their shells and skin are not green as the name might imply – their coloration is more of a brown/yellow/white mixture. They are called green turtles because their fat is green. Green sea turtles are the only species in which the adults are completely herbivorous (vegetarian) and eat primarily sea grass. Green juveniles are carnivorous like other species, though, and their digestive system actually changes as they mature to allow for this dietary shift. Green turtles’ large intestines actually double in length in order to digest the plant material properly. Because of all the vegetation they eat, their FAT is actually green – which is how they got their name. They can be distinguished from other similar looking species by looking at the scales on their head. Between the eyes, they have a pair of scales where other turtles only have one or several. Their scales are well defined and dark. They are also the only species with jagged edges on their lower beak, these act as pruning shears to take bites of grass.

Green turtles play an important role in the “underwater prairies” of their feeding grounds. The role they play is similar to that of the buffalo on the open prairies in the early days of American colonization. They modify the prairies by eating so much of the excess plant material, stimulating growth in the ecosystem. They will also return to the sites that they previously grazed in order to eat the new sprouts that are full of nutrients. It’s estimated that there are only between 3-9% of green sea turtles left from their pre-human numbers. The reduction of green sea turtles can have serious repercussions for the marine grasslands they modify. The marine grasslands are very important to the ocean as a whole because they act as nurseries for many species, and it is one of the most productive ecosystems in the world.

Green sea turtle feeding on sea grass. Photo credit: http://www.flickr.com/photos/32328358@N07/page9/

Green turtles become sexually mature at between 12 and 50 years depending on where they feed and what they were able to eat. Their nesting season is between June and September, and they are noted to have high nest fidelity. In other words, they commonly return to the same beach to nest each season that they reproduce. They lay 1-7 clutches/year, and usually have 13 days between each nest.

Green turtle nesting. Photo credit: http://www.the-islander.org.ac/artd_6187_02_2009_60.html.

Green turtle females are said to be more skittish than other types of sea turtle females, and frequently have false crawls. Like the leatherback, green turtles have a unique gait as adults – moving both front limbs at the same time, then both back limbs. The hatchlings, however, use the alternate gait. Hatchlings also have the added advantage of countershading – meaning that they have dark carapaces and light colored plastrons to help camouflage them from both underwater and aerial predators.

As I mentioned in my previous blog, fibropapillomatosis is a debilitating skin disease that particularly affects green sea turtles. In fact, it’s estimated that 40-60% of green sea turtles in Florida are affected by it. However, this disease is a small problem compared to the impacts that humans are causing the species. They are still frequently hunted in some countries for their fat, meat and skin. They are used frequently in green turtle soup. Historically, green turtles actually played an import role in allowing the Spanish colonization of America. They provided a valuable food source to the colonists. Currently, loss of nesting habitat is the biggest threat in the United States.

"Lavender" is a Kemp's ridley sea turtle. Kemp's ridleys are the most critically endangered sea turtle in the world. Since admitting our first Kemp's ridley patient in 2005, NMLC has cared for 19 of this species.

Today is Endangered Species Day.  The U.S. Fish and Wildlife Service observes Endangered Species Day “…in order to recognize the national conservation effort to protect our nation’s endangered species and their habitats.”

We’d like to recognize the 74 endangered and threatened species that the National Marine Life Center has cared for over the past six years.  Our mission to rehabilitate marine animals is especially compelling when considering endangered species.  The population numbers of endangered species are so low that every individual matters in that population.  Each individual we can rehabilitate or headstart and release back into the wild helps their population recover.

Fletcher is a loggerhead sea turtle. Currently listed as "threatened", loggerheads' population numbers in the US have continued to decline and they are being proposed for uplisting to "endangered" status. Since accepting our first patient, "Eco", in 2004, NMLC has cared for 2 loggerheads.

Please donate to the National Marine Life Center and help us open our new marine animal hospital so we can save more endangered and threatened marine animals.  Every gift matters.  Thank you.

Northern red-bellied cooters are listed as "threatened" on the federal endangered species list and "endangered" at the state level. NMLC participates in a state-managed "head start" program that has increased hatchling survivability by over 90%. Because of our veterinary expertise, we are often asked to care for animals from the headstart program that need medical attention. Since becoming a partner in the head start program, NMLC has cared for 37 cooters.

Patty is a diamond-backed terrapin listed as "threatened" within Massachusetts. NMLC helps terrapin researchers by overwintering hatchlings and rehabilitating sick turtles. Since admitting our first diamond-backed terrapin in 2008, NMLC has cared for 16 terrapins.

Fletcher, the 70-pound loggerhead sea turtle rehabbed at the National Marine Life Center and released from Atlantic Beach in North Carolina on May 18th, is now sending signals of its ocean trek via satellite.

You can track Fletcher’s progress by clicking on the image above or on these words, which will take you to Fletcher’s page on the SeaTurtle.Org web site.  To track other animals rehabbed at the National Marine Life Center and equipped with a satellite transceiver, click here. or go to the “Tracking” page at the top of our web site.

Good luck, Fletcher!

Fletcher, the loggerhead sea turtle that stranded cold-stunned in Truro last fall, was released back into the Atlantic Ocean this afternoon at Atlantic Beach in North Carolina.  Readers will recall that Fletcher spent the winter at the National Marine Life Center in rehabilitation, gaining nearly 20 pounds before heading south for her release.  See Fletcher gets ready for release!

Looking closely at Fletcher’s carapace (her top shell), you can see the antenna rising from a satellite transmitter.  We’re planning to monitor Fletcher as she returns to the wild and use the information she provides us to better understand loggerhead sea turtle behavior in the Atlantic Ocean.  Check this web site often for Fletcher’s progress as we track her position.

So long, Fletcher, and good luck!  We’ll be watching you.

Fletcher is a loggerhead sea turtle who stranded, cold-stunned, on November 28, 2008 in Truro.  He was rescued by volunteers from the MassAudubon Wellfleet Bay Wildlife Sanctuary, triaged at the New England Aquarium, and transferred to NMLC on December 4.  After four months of rehabilitation, Fletcher was ready to be released back into the wild!

In preparation for release, NMLC veterinary staff tagged Fletcher with flipper tags, a “PIT tag” or microchip, and a satellite tag so we may track his progress in the wild.  Click here for photos by the Cape Cod Times.  Fletcher was transported to Virginia for release into the warm waters of the Gulf Stream.