Atlantic Leatherback Sea Turtles May Get Endangered Status

Female leatherback turtle digging in the sand in USVI - via Wikimedia

Federal wildlife officials say they are reviewing the status of a sea turtle that lives in the northwestern Atlantic Ocean to see if it should be listed as threatened under the Endangered Species Act.

The National Marine Fisheries Service says it is conducting the review of the Northwest Atlantic population of leatherback sea turtles. The turtles live all over the world, including off of the mid-Atlantic states, New England and Canada.

Sea turtles spend almost their entire lives in the sea, and when active they often come to the surface to breathe, but can remain underwater for several hours at a time while resting.

Though most sea turtles inhabit warm, tropical and subtropical waters, they migrate northward as water temperatures increase in the late spring and summer and remain in northern waters until late fall. From late May until November, New Jersey's coastal waters provide important seasonal foraging habitat.

The leatherback (Dermochelys coriacea) gets its common name for its unique shell which is composed of a layer of thin, tough, rubbery skin, strengthened by thousands of tiny bone plates that makes it look “leathery.” The leatherback is the only sea turtle that lacks a hard shell.

Leatherback turtles are the world's largest sea turtles. They can weigh up to 2,000 pounds. They are also the deepest diving turtle with dives of more than 4,000 feet below sea level.

They range in size as adults from 4 to 6 feet (130 – 183 cm), but the largest leatherback ever recorded was almost 10 feet (305 cm) from the tip of its beak to the tip of its tail and weighed in at 2,019 pounds (916 kg). 660 to 1,100 pounds (300 – 500 kg) is typical.

Leatherbacks have delicate, scissor-like jaws that would be damaged by anything but soft-bodied animals. Surprisingly, they feed almost exclusively on jellyfish which are composed mostly of water and not a good source of nutrients. This penchant for jellyfish also makes them vulnerable to plastic bags and trash in oceans which resemble jellyfish in the water.

Leatherbacks are listed as vulnerable by the International Union for Conservation of Nature. The fisheries service says it's collecting comments until Feb. 5 about whether the northwestern Atlantic's population should be included on the U.S. Endangered Species list.

More Info

• conserveturtles.org/information-about-sea-turtles-leatherback-sea-turtle
• nationalgeographic.com/animals/reptiles/l/leatherback-sea-turtle
• conservewildlifenj.org/species/fieldguide/view/Dermochelys%20coriacea

Loggerhead Turtles

Loggerhead turtle
via http://upload.wikimedia.org/wikipedia/commons/8/8e/Loggerhead_sea_turtle.jpg

A recent review on movies.nytimes.com of the new film Turtle: The Incredible Journey got me thinking about this endangered species that visits New Jersey waters.

Though the reviewer is critical of special effects enhancements in the film, there's no doubt that the story is compelling.

The journey of the loggerhead turtle is, by any measure, an amazing life voyage, one that here reaches from the beaches of Florida to the eerie calm of the Sargasso Sea and the watery speedway known as the Gulf Stream before heading to Africa and then the call of motherhood. It’s a trip that eats up thousands of miles, takes some two dozen years and is fraught with dangers, though sometimes in the movie that threat may be more imaginary than actual, as when a basking shark, the second largest fish in the world, cruises by with its weird wide mouth open, yawning in water and prey. Armed with little teeth, the basking shark feeds on krill and plankton, but its size and cavernous mouth do make for dramatic viewing.

In 1978, loggerheads were listed as threatened and in 1979 the state of New Jersey classified four marine turtles - the Atlantic hawksbill, loggerhead, ridley and leatherback turtles - as endangered. (Also the Atlantic green turtle as threatened.)

Adult Atlantic loggerhead turtles, Caretta caretta, weigh from 170 pounds (77 kg) to 350 pounds (159 kg) and measure 31 inches (79 cm) to 45 inches (114 cm). The loggerhead sea turtle is omnivorous, feeding mainly on bottom dwelling invertebrates. Its large and powerful jaws serve as an effective tool in dismantling its prey.

The greatest concentration of loggerheads is along the southeastern coast of North America and in the Gulf of Mexico, but they are common throughout the temperate and tropical zones around the globe.

Scientists from the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration proposed last year a reclassification of the loggerhead sea turtle’s designation from “threatened” to the more critical “endangered” category. That tells you that most efforts to protect the species have been ineffective.

The loggerhead sea turtle is found in the Atlantic, Pacific, and Indian oceans as well as the Mediterranean Sea. It spends most of its life in saltwater and estuarine habitats, with females briefly coming ashore to lay eggs.

One problem the loggerhead sea turtle encounters today is that it has a low reproductive rate. Females lay an average of four egg clutches and then become quiescent, producing no eggs for two to three years. The loggerhead reaches sexual maturity within 17–33 years and has a lifespan of 47–67 years.

Untended fishing gear is responsible for many loggerhead deaths. Turtles may also suffocate if they are trapped in fishing trawls. Turtle excluder devices (TEDs) have been implemented in efforts to reduce mortality by providing the turtle an escape route.

Two other problems are the increasing loss of suitable nesting beaches, and the introduction of exotic predators has also taken a toll on loggerhead populations.

It is also more difficult to protect this species because it requires international cooperation since the turtles roam vast areas of ocean and critical nesting beaches are scattered among several countries.

The young loggerheads are threatened by a number of predators and the eggs are especially vulnerable to terrestrial predation.

Once the turtles reach adulthood, their formidable size limits predation to large marine organisms such as sharks.

Turtle: The Incredible Journey

Turtle: The Incredible Journey - Trailer from Rockfish on Vimeo.

Gulf of Mexico Oil Spill's Biggest Victims?

Sea turtles may be the Gulf of Mexico oil spills biggest victims. Already 25 turtles have been found washed up on Mississippi’s shorelines.

Kemp's Ridley

Autopsies are being done to confirm whether or not their deaths are linked to the oil spill. If it is determined that the oil spill is the cause of death in the turtles the oil could have harmed the turtles in many different ways. Experts say that contaminants, such as oil, can lead to changes in a sea turtles immune system. Contaminants can also cause liver damage and lead to changes in the turtle’s protein and carbohydrate regulation. Experts report that hydrocarbons released by oil can trigger pneumonia, if these chemicals enter the lungs. Red blood cells can also be damaged.

One particular sea turtle, the Kemp's Ridley turtles in the Gulf of Mexico are of particular concern in this disaster as they are listed on the Endangered Species List.

http://www.nmfs.noaa.gov/pr/species/turtles/kempsridley.htm

Marine Turtles and New Jersey

As a result of declines in the populations of several marine turtle species, the federal government listed the Kemp's ridley as endangered in 1970, the same year it also listed hawksbill and leatherback turtles as endangered.

In 1978, it listed loggerheads as threatened and green turtles as threatened and, in the case of the green turtle's Florida and Mexico breeding populations, as endangered.

In response, in 1979 the state of New Jersey classified the Atlantic hawksbill, loggerhead, ridley and leatherback turtles as endangered and listed the Atlantic green turtle as threatened.

Kemp's ridley turtle
Photo: http://www.nmfs.noaa.gov

MARINE TURTLES and NJ
Atlantic loggerhead turtle, Caretta caretta
Status: State: Endangered    Federal: Threatened

Atlantic leatherback turtle, Dermochelys coriacea
Status: State: Endangered    Federal: Endangered

Kemp's ridley turtle, Lepidochelys kempi
Status: State: Endangered    Federal: Endangered

Atlantic green turtle, Chelonia mydas
Status: State: Threatened   Federal: Threatened/Florida and Mexico breeding populations endangered

Loggerhead Turtles May Move From Threatened to Endangered

via Global Adventures

Scientists from the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration have proposed to re-classify the loggerhead sea turtle’s designation from “threatened” to the more critical “endangered” category. Environmental groups say that the proposal could be a turning point leading to greater protection.

Adult loggerhead sea turtles weigh from 170 pounds (77 kg) to 350 pounds (159 kg) and measure 31 inches (79 cm) to 45 inches (114 cm). The greatest concentration of loggerheads is along the southeastern coast of North America and in the Gulf of Mexico, but they are common throughout the temperate and tropical zones around the globe.

Photo: Global Adventures

Marine Turtles in New Jersey Waters

Green turtle surfacing for air

In New Jersey, we have 4 marine turtles that are protected.

1. Atlantic loggerhead turtle, Caretta caretta - NJ Status: Endangered, Federal Status: Threatened
2. Atlantic leatherback turtle, Dermochelys coriacea, NJ & Federal: Endangered
3. Kemp's ridley turtle, Lepidochelys kempi, NJ & Federal: Endangered
4. Atlantic green turtle, Chelonia mydas, NJ  & Federal: Threatened
5. Atlantic hawksbill turtle, Eretmochelys imbricata, NJ & Federal: Endangered

Last week, cold-stunned Kemp's Ridley sea turtles began to wash up on Cape Cod beaches which unfortunately marks the beginning of the turtle stranding season here in the Northeast.

As water temperatures dip below 50 degrees, it becomes too cold for the sea turtles. These species should have moved south for the winter by now, but some marine reptiles get fooled by ocean anomalies around Cape Cod and Long Island.

Turtles described as "cold stunned" are in a torpid state with heart rates slowing down to as low as one beat a minute. They can appear to be dead, but this state actually allows the turtles' bodies to survive as the turtles can bury themselves in the mud on the bottom of the sea and survive for a few weeks in waters below 50 degrees.

Of course, they can survive the entire winter that way, so stragglers that wash up on the beach can be rescued by volunteers.

Unlike land turtles from which they evolved more than 150 million years ago, sea
turtles spend almost their entire lives in the sea. When active, they often come to the
surface to breathe, but can remain underwater for several hours at a time while resting.

Leatherbacks can dive to more than 3,000 feet below sea level. Their habitat preference is based on their preferred diet. Adult green turtles are herbivores, or plant eaters. All the other sea turtles are either carnivores (meat-eaters) or omnivores that eat both plant matter and meat.

Kemp's Ridley

The Kemp's Ridleys, which hatch off the coast of Mexico, are the most endangered of the sea turtles in our water. Kemp's ridley is the smallest of all sea turtles. From above, the short, chunky shell appears broadly heart-shaped to nearly round, with high vertebral projections and serrated edges. Adults weigh between 35 and 42 kg (77-92 lbs.).

The leatherback is the largest of all sea turtles. In fact, the leatherback is one of the largest living reptiles (only some species of crocodiles are larger). It is easily distinguished by its black, leathery skin, huge, spindle- or barrel-shaped bodies and long flippers. Adults generally weigh between 290 and 590 kg (638-1298 lbs.), but can weigh up to 2,000 pounds.

The most colorful sea turtle, the medium-sized hawksbill turtle has an elongated, oval shell
distinguished by overlapping scutes on the carapace.Color varies widely, from very bright colors to heavy dark brown (in the eastern Pacific).

Overharvesting of eggs for food, intentional killing of adults and immatures for their shells and skin and incidental drowning in commercial fishing gear are primarily responsible for the worldwide decline in sea turtle populations. Coastal residential and resort development has also degraded nesting habitat, and pollution of oceans threatens foraging habitats.

The federal government listed the Kemp's Ridley as endangered in 1970, the same year it also listed hawksbill and leatherback turtles as endangered. In 1978, it listed loggerheads as threatened and green turtles as threatened and, in the case of the green turtle's Florida and Mexico breeding populations, as endangered. New Jersey classified the species in 1979.