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.

Photo by Kate Shaffer.

Admittedly, I know very little about sea turtles. After starting my internship at the National Marine Life Center I decided to order a book specifically dedicated to the biology and behavior of these mysterious oceanic reptiles. One interesting fact I came across while reading was that the temperature at which the eggs are incubated determines whether or not the turtle will be male or female.Most vertebrates have sex chromosomes (XX for female and XY for male), however, sea turtles lack these chromosomes.

Females need warmer temperatures in order to develop. For example, in green turtles, temperatures need to be 88 F or above for the eggs to become females. For males to develop the temperature is around 82 F. If the temperature of incubation falls somewhere between 82 and 88 F, a mixture of the sexes develop. Heat produced by the eggs themselves can also contribute to the incubation temperature – eggs in the center of the nest become females and the eggs along the periphery become males (Spotila 2004).

If temperature affects the sex ratio of sea turtles, how might climate change impact populations in the future? Currently, sea turtle populations that nest in the southern portion of the United States are predominately female biased. It has been suggested (Hawkes 2007) that if there is even a 1 C warming of average temperatures, an even more significant bias could occur. If average warming exceeds 3 C, mortality rates of the eggs may also occur.

Climate change may also affect the nesting grounds of turtles if sea levels rise. Beaches currently being used by turtles may vanish under the sea. Ocean acidification (caused by increased CO2 levels) could potentially alter the sediment of the beaches, which may lead to inadequate conditions for incubation (Fuentes et al 2011). Sea turtles select their nesting sites based on several factors, such as low salinity, sufficient space above the hide tide line, adequate vegetation (for some species), high humidity, etc (Hawkes 2007). All of these may be affected by an increase in average global temperatures.

Future studies need to be conducted to better estimate the current sex ratios of the various sea turtle species in order to better predict how these will be affected by changes in nesting/incubation environments. Some possible ways that sea turtles may prevent extremely biased female sex ratios are by nesting earlier (cooler periods), nesting at higher latitudes (more north), changing the depth at which they bury their eggs, or changing the type of substrate they bury their eggs in (i.e. type of sand). That way more eggs will develop into males that might have otherwise been females (Fuentes 2011).

Just recently (August 18 2011), the first sea turtle nest was discovered in Delaware. Sea turtles are not known to nest that far north as well as that late in the season. They typically lay their nests on the coasts on South Carolina, Georgia and Florida. Alex Hoar, the U.S. Fish & Wildlife Service’s Northeast Endangered Species Coordinator said that, “And with global warming, events such as this may be a sign of what is to come” (Delaware Online).

Sources:

Fuentes M.M.P.B, Limpus C.J., Hamann M. 2011. Vulnerability of sea turtle nesting grounds to climate change.  Global Change Biology. 17(140-153)

Hawkes L.A., Broderick A.C., Godfre M.H, Godley B.J. 2007. Investigating the potential impacts of climate change on a marine turtle population.  Global Change Biology: 13(923-932)

Spotila, James R. 2004. Sea Turtles: A Complete Guide to Their Biology, Behavior, and Conservation. The Johns Hopkins University Press.

Sea turtle’s nest is so egg-citing:  Sea turtle lays her eggs at Cape Henlopen in what may be the first such nesting herehttp://www.delawareonline.com/article/20110819/NEWS08/108190348/Sea-turtle-s-nest-egg-citing

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.

Sea turtle swims in North Madagascar. Photo credit: http://www.allposters.com/-sp/Sea-Turtle-Swimming-Underwater-Nosy-Be-North-Madagascar-Posters_i5264967_.htm

As you may have read in my previous blog (Sea Turtles Part 1) or in Alexa’s blog (New England Aquarium Adventure), the National Marine Life Center interns took a trip to the New England Aquarium last week. While we were there, we animal nerds got our fill of marine life from all over the world. For me, of course, the sea turtles were the most exciting part! While visiting the gift shop, I obtained a wonderful book called Sea Turtles of the Atlantic and Gulf Coasts of the United States. It has really been a wonderful resource for me to deepen my understanding of sea turtles biology, behavior, and the things that threaten them in the wild. I’ve learned so much, in fact, that I’ve had to split up my sea turtle blog into several parts. This section deals with the things that threaten turtles, some of these problems are unique to sea turtles, others are quite common among marine animals throughout the ocean: disease, predators, human impacts and the conservation efforts being done to counteract these threats and save these animals.

Disease

One of the most common diseases that affect green sea turtles is fibropapillomatosis. Fibropapillomatosis is a debilitating skin disease that affects sea turtles all over the world. This skin disease causes the turtles to develop tumors on their skin. Though it most commonly affects greens, it has also been documented in loggerheads, Kemp’s ridleys, olive ridleys and leatherbacks. This disease can be fatal if it invades the turtle’s internal system, but will often heal if the tumors are superficial. Scientists also think that this could be a virus because herpes was found in 95% of all Florida cases.

Turtle showing symptoms of fibropapillomatosis. Photo credit: http://nmlc.org/wp-content/uploads/2011/07/fibropapillomatosis.png.

Internal parasites

There are a number of internal parasites found in sea turtles. Some of the most common ones include flatworms and blood flukes. In fact, 33% of loggerhead sea turtles on the east coast are found with disease-producing blood flukes.

Blood fluke. Photo credit: http://onlinesurgicaltechniciancourses.com/2010/17-disgusting-parasites-that-might-live-inside-you-right-now/

Flatworms are also frequently found in sea turtles. All species of flatworms are found in the gastrointestinal tract  except for one that has been found in the bladder. Though these flatworms are parasites, they do not necessarily seem to cause weakness to the turtle. Most wild turtles will have some kind of parasite on or within it, but until the population increases to a high number, the parasite may not be debilitating to the animal.

Roundworms are also found in the stomach or intestinal tract of sea turtles, but frequently the turtle will show no indication of a negative impact caused by these parasites.

Roundworms. Photo credit: http://wallpaperactristsbollywood.blogspot.com/2011/05/infected-with-roundworm.html.

External parasites

Some of the common external parasites found on sea turtles include leeches and a number of different species that reside on the shell called epibiota. Leeches are usually seen around where the flippers attach to the rest of the body.

Epibiota on a sea turtle shell. Photo credit: http://www.georgiaseaturtlecenter.org/kids-spot/words-to-know/.

Epibiota is found on the shell, and these organisms can include barnacles, mollusks, polychaetes, amphipods and algae. Both leeches and epibiota are found most commonly on loggerhead sea turtles. Typically, epibiota doesn’t seem to affect the sea turtle; the organisms and the turtle are in a “commensal” relationship. So, the epibiota benefit from the association, and the turtle receives no benefit or detriment from their presence. A healthy turtle can control the amount of organisms by scraping them off with its flippers. Also, as the turtle grows it sheds the scutes (or shell scales) and so some organisms will be evicted that way. However, if a turtle is sick, it may not be strong enough to control the orgasms, and the internal and external parasites will compound. If too many organisms find a home on the turtle shell it reduces the turtle’s speed and drag it down. If the turtle doesn’t scrape them off right away though, they can potentially become permanent residents. Some barnacles are actually only found on sea turtle shells!

Predators and Dangers

Eggs

Nest cavity depiction. Photo credit: http://www.turtletime.org/.

So after a mother sea turtle lays her eggs in a nest chamber on the beach, the dangers begin for the baby turtles. The eggs can be easily trampled by careless humans or other large animals traversing the beaches. If some eggs are trampled or cracked open by predators, it not only releases a scent that makes them easier to find, but can contaminate the clutch and kill far more turtles than were initially consumed. In leatherback and hawksbill nests, “false eggs” are frequently found – these are just shelled albumin. These eggs are often much smaller than eggs containing a developing embryo and are sometimes even dumbbell shaped. The function of the false eggs is currently unknown, but it must have some kind of evolutionary advantage. Some hypotheses include keeping moisture high in the nest or maybe even distracting predators.

Leatherback eggs showing false eggs. Photo credit: http://www.thesea.org/TheSea/leatherback_sea_turtles.html

When a turtle is hatching from the egg, it uses a caruncle (egg tooth), a hard appendage on the top of its beak to break through the shell.

Caruncle. Photo credit: http://www.georgiaseaturtlecenter.org/kids-spot/words-to-know/.

In order to avoid the most predators, hatchlings usually hatch at night, though this is not foolproof because there are nocturnal predators as well. The hatchlings on the top of the nest can feel if it’s time to rouse the rest of the hatchlings if the sand above the nest is cool or warm, indicating night or day. If the top turtles start digging and wiggling around in the nest, the others will follow. Usually they go about this in spurts, all digging for a while, then all resting, until finally they break through the top and are able to move together out of the nest. Those who hesitate lose the advantage of surprise, and have a less likely chance of reaching the ocean undetected. The most common predators of eggs and hatchlings include ghost crabs, sea birds, bears, raccoon, feral pigs, ants, armadillos, feral/domestic dogs and, of course, humans.

Hatchlings

Hatchlings face many of the same predators and dangers that the eggs do, plus some. In the water they face big fish, sharks and much more. Also, once sea turtles reach the ocean, they are solitary animals, though they are sometimes seen in groups because of similar migration routes. Hatchlings face human-caused dangers as well – like light pollution. Hatchlings use the brightest light source as a way to navigate back to the ocean. We think that maybe they’re looking for the moon reflecting off the waves. However, if the brightest light source isn’t the ocean, and it’s actually a street light or house, turtles will head in the wrong direction. If hatchlings are heading away from the ocean their chance of being spotted by terrestrial predators goes up significantly, they also only have a small amount of energy left from the nutrients they received from the egg, so they can starve. They can also fall into holes or gutters and become trapped.

Leatherback hatchling headed for the ocean. Photo credit: http://www.catchconservation.com/turtles/.

Juveniles/Adults

Adults and juveniles face similar dangers. Human caused issues stem frequently from pollution, bycatch, entanglement, destruction of habitat (including nesting beaches) and active harvest.

Pollution is a huge issues for turtles, specifically littering. Turtles often mistake plastic bags floating at the surface for food, and this is fatal. It can either cause an obstruction in the digestive tract, or it will make the turtle feel as though it’s full even though it’s not getting any nutrients, and it will starve to death. If fishermen do not responsibly dispose of their fishing line, turtles can easily become entangled. Fishing line may look relatively harmless, but it can easily cut into marine animals’ skin and cause deep wounds, infections, and even painful amputation. For more information on entanglement or how to properly dispose of fishing line, see my previous blog: Monofilament Recycling Program Underway.

The fishing industry also takes a toll on sea turtle numbers. Sea turtles are frequently victims of boat strikes. In fact, back home in the midwest, the Omaha Henry Doorly Zoo in Omaha, Nebraska is currently caring for a sea turtle that was hit by a boat in 2002 and deemed unreleasable. Her name is Bubbles and she is a 15-20 year old green sea turtle. For more information on this particular turtle please see: Omaha World Herald News Article or Omaha Zoo\’s press release.

Bubbles receiving a CT scan, courtesty KETV News.

Turtles are frequently caught in fishing nets as “bycatch” – this means that they were accidentally caught. Because turtles breathe air, if they get stuck in fishing nets and are unable to surface, they easily drown. Even if they somehow manage to get out in time, they often die of shock. TEDs (turtle excluder devices) became a mandatory piece of equipment for all trawlers fishing in US waters. These are a device that attaches to the net so that large objects (like sea turtles) will be released from the net without affecting the fisherman’s catch size. This is somewhat of a controversial issue. Because turtles experience shock from going through the fisherman’s nets, many of those that are freed from the nests will still die. Some say that the TEDs are greatly reducing turtle mortality, others, such as the author of my new sea turtle book, say that turtle deaths are actually increasing since use of the TEDs was implemented.

A diagram depicting how TEDs work. Photo credit: http://www.seaworld.org/infobooks/SeaTurtle/stconser.html.

Of course, there is also a continuing problem with deliberate hunting in many countries. There’s still a market for sea turtle eggs and meat, and though education around the world about the need to conserve these animals is increasing, many people still kill nesting females and harvest eggs.

In addition to human caused dangers, turtles also face natural dangers. Even adult sea turtles have a couple predators like sharks and orcas. But don’t think that turtles are by any means an easy food source: Sea turtle vs. Shark.

The last threat I want to discuss is a huge issue in Cape Cod – cold stunning. If you haven’t heard, Cape Cod is a stranding hotspot – in fact it’s the third in the world next to a place in Australia and another in New Zealand! This is due to the unique geographic feature that is the Cape Cod hook.

Turtles follow the gulf stream into the Cape Cod hook and often can't get back out.

Turtles follow the Gulf Stream up north to the Cape, and find a great foraging area here. However, when it comes time for the turtle to go south for the winter, its instincts tell it to go south, and the turtle can’t figure out that it needs to go north to escape the hook and get out into open ocean.

Because turtles are reptiles, they are ectothermic or cold-blooded. This means that their body temperature depends on the temperature of the environment around them. So, as winter approaches and the water temperature drops, so does the turtles’ body temperature. Eventually they will go into hypothermic shock, this is also called cold stunning. Their heart rates drop and they wash up on the beaches, and then they are taken to rehabilitation facilities (such as the National Marine Life Center!) where their body temperatures are warmed up very slowly (just a couple of degrees a day) until they are warm enough to be put into a tank. They are then housed until spring/early summer when they are released on the southern side of the cape toward open ocean.

YOU CAN HELP!

There are things great and small that everyone can do to help sea turtles and all wildlife.

• Donate: the NMLC needs your help to complete our hospital so we can care for our turtles that are entangled, struck by boats, or cold-stunned. Our timeline is not based on what needs to be done – but rather how we’re going to fund it!
• Volunteer: Organizations such as the NMLC and Mass Audubon Society always need help. Mass Audubon is a sea turtle rescue program. There are plenty of great wildlife programs that could use your experience/expertise in whatever field you’re in!
• Don’t litter: Obviously, please discard of your garbage and fishing line responsibly, especially your plastic bags! If you come across trash, please help by cleaning it up!
• Pass it on: teach your friends, relatives, and colleagues about the trials turtles and other marine animals face so that we can make a difference together.
• Enjoy wildlife from a distance: Your presence is stressful to the animals and your respect is much appreciated.
• Call the professionals: If you come across a wounded or stranded animal, NEVER approach a wild animal without professional assistance or permission. Sea turtles and marine mammals are protected by the federal government and these animals can carry a wide array of zoonotic diseases!

For more specific information on each turtle species, see my next blog: Sea Turtles! Part 3.

Photo credit: http://www.theanimalfiles.com/reptiles/tortoises_turtles/green_sea_turtle.html

My ultimate goal for interning at the National Marine Life Center this summer is to get some marine animal care and education experience for my future. In two years I will be entering graduate school, and looking to further my education in sea turtle conservation. On Monday, the other interns and I took a field trip out to Boston to check out the New England Aquarium to get a chance to see some animals and “nerd out” together. It was truly a great experience for all of us because we got a chance to learn from each others’ backgrounds. Last summer I worked as a reptile care intern at Omaha’s Henry Doorly Zoo, so I felt like my trip to the aquarium worked like a bridge to connect my previous experience with animal care and husbandry with my current work trying to learn about marine animals and education. While we were at the aquarium, I bought a great book called Sea Turtles of the Atlantic and Gulf Coasts of the United States. Though I’ve only read bits and pieces of it, I’ve learned so much already, and so for this week, we’re going to talk about some things that I knew, and some things that I’ve learned. My passion: sea turtles!

To start off, sea turtles are reptiles. The main characteristics of reptiles are:

1. They are air-breathing, so they have lungs just like humans.

2. Reptiles are “cold-blooded,” or ectothermic, which means that the temperature of their body is greatly affected by the temperature  of the air or water around them.

3. Reptiles lay eggs.

4. They have scales covering their skin.

Sea turtles are unique among freshwater turtles and tortoises because they can’t withdraw their head or limbs into the shell. Their shell is designed to be hydrodynamic, as many may never leave the ocean unless they are ill or nesting. Evolution sacrificed the space necessary for the added defense of pulling into the shell for the added speed of the sea turtle shell design.

General Turtle Anatomy

Sea turtles, like other turtles and tortoises, do not have teeth. They have a hard beak called the rhamphotheca, and in some species the lower jaw is serrated, while in other’s it is smooth but sharp.

Photo credit: http://www.scubadivinginplayadelcarmen.com/playa-del-carmen-marine-life-guide/sea-turtles.htm

The top part of the turtle’s shell where the “back” is is called the carapace.

The bottom part of the shell where the “belly” is, is called the plastron.

Green sea turtle showing plastron. Photo credit: http://www.vims.edu/newsandevents/topstories/archives/2009/green_sea_turtle_release.php

The area on the side that connects the two is called the bridge. The scales on the shell are called scutes.

It is very difficult to tell a live sea turtle’s age. You can take an estimate based on size, but the size may not always be an accurate description of age in sea turtles. Especially once adults have reached sexual maturity, their growth slows greatly and nearly stops, so unless you’ve tagged it, you may be completely unable to tell the age of the animal.

A researcher putting a tag in the flipper of an Olive Ridley sea turtle. Photo credit: http://www.visualphotos.com/image/1x9147179/olive_ridley_sea_turtle_lepidochelys_olivacea

Adult male sea turtles can be distinguished from females by looking at the tail. In males, the tail is quite long, extending far from the back edge of the shell. This is because residing within the tail is the male sex organ used for copulation.

You may be curious about how a sea turtle is able to process all the salt that it ingests from the salt water it lives in. Sea turtles have special glands near their tear ducks called lachrymal glands. These glands excrete excess salt in their bodies so the animal doesn’t get dehydrated.

There are 7 species of sea turtles, 5 of which we see in Cape Cod. These are the leatherback, green, loggerhead, Kemp’s Ridley, Hawksbill, Olive Ridley, and flatback.

Mating Behavior

Sea turtles are polygamous, which means that both males and females may mate with many partners. Sea turtles don’t only have many partners in a lifetime, but they will have many partners in each nesting season. In fact, a clutch of turtle eggs may be the product of many fathers.

Sea turtles mating. Photo credit: http://www.archelon.gr/eng/biology.php

Females choose who they mate with. If they are approached by a partner that is not suitable, she will frequently cover her cloaca (the hole where waste is excreted and where copulation takes place) with her back flippers and settle on the ocean bottom until the male goes away or until she needs to surface to breathe. Mating is not a fun task for adult turtles. Males will often bite females on their neck and flippers, leaving open wounds that heal slowly, often taking weeks to do so. Males will compete to mate with the female, so if one male is mating with a female, another male will frequently approach and try to pry the male off, or bite his head, flippers, or even his tail.

Males competing for access to a female. Photo credit: http://seapics.com/new-pictures/2008/2008-01-new-pictures.html

Males in many species use the claws that appear on their front flippers to hang on to the female’s carapace during mating.

Nesting Behavior

Females will produce hundreds of eggs during a nesting season, and it takes a toll on the animal’s body. This is why females don’t participate in nesting every year, they will usually lay eggs every 2-4 years. Females must leave the ocean and come out on the beach to lay their eggs. Most sea turtles lay their eggs at night in order to expose their eggs to fewer predators. Also, turtles don’t put all their eggs in one basket – so to speak.

A female leatherback returning to the ocean after nesting. Photo credit: http://seaturtles.photoshelter.com/gallery-image/Sea-Turtle-Images/G0000_8GK4yEUHhc/I0000ga8IbbcTvGo

Sea turtles will lay many nests in a season, with approximately 100 eggs per nest. She will come out, dig a hole in the sand with her back flippers, deposit the eggs in the sand, and then cover the eggs and fling sand everywhere in order to disguise the nest. She then returns to the ocean and will mate again and come back to the beach in a few days or a few weeks and lay another nest. If a female attempts to come up on land to lay her eggs, but is scared by the presence of humans or potential egg predators, she will return to the sea and lay her eggs somewhere else along the beach or at a later time, and these tracks are referred to as “false crawls.” Females also tend to return to the same beach that they hatched from to lay their eggs, this is called “nest fidelity.”

As in other reptiles, turtles have temperature dependent sex determination. What this means is that the temperature of the nest determines whether there will be more males or more females in the nest, and after certain temperatures the nest will be all male or all female. For sea turtles, warmer temperatures produce females and cooler temperatures produce males. A phrase I use to remember which temperature produces which sex is ”hot chicks and cool dudes.”

Green sea turtle nest. Photo credit: http://www.allposters.com/-sp/Green-Sea-Turtle-Eggs-in-a-Nest-on-a-Beach-Chelonia-Mydas-Pacific-Ocean-Borneo-Posters_i6011847_.htm

The turtle eggs will incubate for 50-65 days before they begin to hatch. Find out more details about the life cycle of sea turtles and the dangers they encounter in my next blog: Sea Turtles! Part 2.

Cool Stuff:  Sea Turtles of the North East is a fun and informative video that takes viewers on an educational tour of the National Marine Life Center. Animated sequences along with video footage illustrates the five species of sea turtles that visit the waters off the Northeast. Kids learn about the importance of marine biology and conservation of the oceans off of Cape Cod, as well as the efforts of the NMLC to rescue and rehabilitate cold-stunned sea turtles. Educators will be able to use this video as a teaching tool that entertains and teaches kids about the science of marine life and the importance of ocean and marine animal conservation.

Check out a clip of the video.

This video is available for sale at the National Marine Life Center’s gift shop, open 10 am – 5 pm daily during the summer.  All video proceeds benefit NMLC’s marine animal rehabilitation programs.

A special THANK YOU to Gregg Seibert and Purple Turtle Productions for creating and producing this video!

Sea Turtle filter system and filter media at the NMLC

We are one step closer to getting the first two pools up and running in the Sea Turtle Ward. The 1,850 pounds of filter media needed to run our filtration system arrived at the new animal hospital yesterday. This filter media will be used to fill the two large sand filters which are a vital part of the turtle life support system. Each tank in the new hospital will have its own filtration system. This allows the water in each system to remain separate and maintain quarantine between pools. Each system will have a mechanical, biological, and chemical filtration component to clean the water. The sand filters provide the mechanical filtration component by removing particulate matter from the water. The sand filters for our first two pools each require 650lbs of silica sand and 275lbs of pea gravel to run properly.

Volunteer Matt Shaffer loads the donated pea gravel at Cape Cod Aggregates

We would like to send a big thank you out to Cape Cod Aggregates who donated the 550lbs of pea gravel for the system, and to the volunteers who helped get the filter media to the NMLC and up to the mezzanine level of the hospital where the filtration systems are located. Thank you to Wendy Wyman and Matthew Shaffer for the donation of their time and use of their vehicles to haul the media. We would also like to thank Josh Shubert, Tyler DeHay, and Kaitlyn Crowley for assisting with the heavy lifting upon arrival at the NMLC. We couldn’t have done it without you!

Volunteers Josh Shubert & Tyler DeHay haul filter media into the new marine animal hospital

Please, VOTE once per day every day in December.
Click on “Vote for This Idea” at:  www.refresheverything.com/nationalmarinelifecenter or
Text 104765 to PEPSI (73774).  Standard text messaging rates apply.

And, help spread the word!
~ E-mail your friends, family, coworkers, fellow students, club members, customers, employees, neighbors, etc. and ask them to vote also.
~ Post flyers on community bulletin boards in your area.  Coffee shops, libraries, post offices, community centers, all are good bets.
~ Share on Facebook, Twitter, LinkedIn, MySpace, and other social media venues.

What could a $250,000 Pepsi Refresh grant do to help marine animals? It could build  several seal and sea turtle rehabilitation pools in our new marine wildlife hospital.  This would allow us to help more sick and stranded animals.  But to win, we need your help.

NMLC's proposed new seal rehabilitation pool. Drawing by cosestudi.

NMLC's new sea turtle ward. Drawing by cosestudi.

On behalf of the animals, thank you.

We’re in the running for a $250,000 Pepsi Refresh Grant to add rehabilitation pools to our new marine animal hospital.  This unique grant program awards funds to the projects with the highest number of votes.  You can vote every day during December!  Vote now and help save stranded seals and sea turtles!

Here’s what you can do:
1) VOTE by clicking HERE, OR by TEXTING 104765 to Pepsi (73774).  (Standard text messaging rates apply.)
2) SPREAD THE WORD!  Share on Facebook, e-mail all your friends and family, tweet on Twitter, post on your blog, hang flyers in your school and/or workplace and/or neighborhood.

On behalf of the animals, thank you!

Toni the Turtle, by Arnold Desmarais. Minimum bid $800.

Cape Cod painter Arnold Desmarais loves the sea.  His well-known seascapes reflect the beauty and diversity of the coast.

A strong believer in giving back to the community, Mr. Desmarais was the first artist to donate work to the National Marine Life Center’s “Art for the Seas” event.  Wanting to contribute something special to this first annual art auction to help stranded marine animals on Cape Cod, Mr. Desmarais painted a piece entitled “Toni the Turtle” just for the occasion.

Art lovers and turtle aficionados alike are invited to bid on this one-of-a-kind painting.  The work will be auctioned at Art for the Seas on September 26.  Minimum bid $800.  For event tickets and information, click here.