caretta-caretta

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Trouble: In July members of the Virginia Aquarium Stranding Response Team rescued a loggerhead sea turtle (Caretta caretta) that had become tangled in crab pot gear in the Chesapeake Bay. Several boats were needed to free the turtle, whose rear flipper was injured. The turtle was named Trouble due to the difficulty of the rescue, and taken to the aquarium for veterinary care. Trouble was returned to the bay today on the beach at Cape Charles, in Northampton County, Virginia. 

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Using infrared lighting, a live-streaming, high-definition “turtle webcam” positioned on a beach in the Florida Keys recorded the hatch of about 100 baby loggerhead sea turtles on Friday, July 25, just before 9 p.m.
The 3-inch-long babies erupted from a hole, came out en masse and headed to the Atlantic Ocean under dim moonlight.

The camera uses infrared lighting so hatchlings won’t be confused by artificial light and will go to sea — guided by moonlight reflecting on the water – instead of pushing further onto land.

Common Name: Loggerhead - named for its exceptionally large head. 

Scientific Name: Caretta caretta

Description: Head is very large with heavy strong jaws. Carapace is bony without ridges and has large, non-overlapping, rough scutes (scales) present with 5 lateral scute. Carapace is heart shaped. Front flippers are short and thick with 2 claws, while the rear flippers can have 2 or 3 claws. Carapace is a reddish-brown with a yellowish-brown plastron. Hatchlings have a dark-brown carapace with flippers pale brown on margins.

Size: Typically 2.5 to 3.5 feet in carapace length (80-110 cm).

Weight: Adult weigh between 155 and 375 pounds (70 -0 170 kg).

Diet: Primarily carnivorous and feed mostly on shellfish that live on the bottom of the ocean. They eat horseshoe crabs, clams, mussels, and other invertebrates. Their powerful jaw muscles help them to easily crush the shellfish.

Habitat: Prefer to feed in coastal bays and estuaries, as well as in the shallow water along the continental shelves of the Atlantic, Pacific and Indian Oceans.

Nesting: Nest at intervals of 2 to 4 years. They lay 3 to 6 nests per season, approximately 12 to 14 days apart. Lays average of between 100 to 126 eggs in each nest. Eggs incubate for about 60 days.

Status: U.S. - Listed as Threatened (likely to become endangered, in danger of extinction, within the foreseeable future) under the U.S. Federal Endangered Species Act. International - Listed as Endangered (facing a very high risk of extinction in the wild in the near future) by the International Union for Conservation of Nature and Natural Resources.

Threats to Survival: The greatest threat is loss of nesting habitat due to coastal development, predation of nests, and human disturbances (such as coastal lighting and housing developments) that cause disorientations during the emergence of hatchlings. Other major threats include incidental capture in longline fishing, shrimp trawling and pollution. Incidental capture in fisheries is thought to have played a significant role in the recent population declines observed for the loggerhead.

Population Estimate*: 44,560 nesting females.

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Testudines 

I am a huge fan of the order Testudines, the turtles!  I’m interested in everything from their biological architecture to their nearly incomparably long lifespans, their reproductive behaviors, habitats, migratory routes, and pretty much every other quirky and fascinating characteristic of our armored reptilian friends.  I feel so privileged that everyday I have the opportunity to sit at a bookshelf underneath the skull of a loggerhead sea turtle (Caretta caretta), which was collected in the 1940’s off of the coast of North Carolina.  For size comparison I included a box turtle species on the left (Terrapene carolina) and a painted turtle species (Chrysemys picta) on the right.  

Loggerheads are fascinating for a number of reasons, one being they are the largest hard-shelled turtle species on the planet. They weigh on average between 250lbs-300lbs (130kg) with some of the largest individuals reaching over 1,000lbs and living up to 67 years.  The earliest they reach sexual maturity is at 17 years old!  They are considered a threatened, endangered, and protected species under many different conservation acts as their oceanic habitats are frequently disrupted by commercial fishing and pollution.  Check out the NOAA page on loggerheads to learn more about their habitats, biology, and conservation efforts! 

Learning more about loggerhead sea turtles’ “lost years”

The migration of North Pacific loggerhead turtles is largely a mystery. Researchers know that the turtles nest and are born on beaches in Japan, and that young turtles vanish into the North Pacific before reemerging 6,000 miles away near Baja California. Researchers are unsure of what happens in between the disappearance into the North Pacific and the reappearance in North America, however, and the time they spend on that part of their migration is called simply “the lost years.”

Not knowing the migration routes of these endangered turtles presents a huge problem for conservationists. If we don’t know where they go, how do we know which areas to protect? How can we protect juvenile loggerheads from human interference – fishing nets in particular – if we don’t even know where they are? Learning more about their migration routes is critical to their recovery and survival. The “lost years” mystery has been solved for Atlantic loggerhead turtles, thanks primarily to the satellite tracking of baby and juvenile turtles. Researchers may now be filling in similar gaps in our knowledge of North Pacific loggerheads.

Pieces of the puzzle began to fall together when, late last year, a NOAA Fisheries marine mammal survey ran across more than 70 juvenile loggerhead turtles 200-250 miles off the coast of Southern California. The turtles, either confirmed or “likely” loggerheads, were less than 20 inches long – the size they would be during their “lost year.” This was the first time that researchers had spotted these lost-year turtles far offshore of California, and while loggerheads do appear in California when the waters are warm, these turtles were younger and much further offshore than the usual California visitors. Researchers believe that they were still following the currents that carry them from Japan to North America. As it was, the juvenile turtles appeared in areas where warm-water eddies met with cold-water eddies, providing abundant food sources upon which the turtles likely depend for their rapid growth.

Researchers with the NOAA Fisheries are hoping to track juvenile Pacific loggerheads, as researchers did with Atlantic loggerheads, to continue filling in the mystery of these turtles’ “lost years” and learn more about their migration route.

  • Based on materials originally written for the NOAA Southwest Fisheries Science Center.
  • Image: One of the juvenile loggerheads spotted off the coast of California. (Credit: Paula Olson)
  • Submitted by volk-morya

Happy World Turtle Day!

Loggerhead turtles (Caretta caretta) are the most common species of sea turtle found in the Sunshine State. Loggerheads can be seen hundreds of miles out to sea as well as in inland bay, marshes, lagoons, and creeks. Their range extends throughout the temperate and tropical regions of the Atlantic, Pacific, and Indian oceans. Individuals can grow to 1.5 meters long and weigh up to 158 kilograms. The turtle’s name comes from its large beaked head.

From May throughout August, thousands of female loggerheads travel to large nesting beaches throughout Florida to lay their eggs. Once a female chooses a nesting site, she digs a pit and then deposits 95-130 eggs into the pit. Next she covers the nest with sand to hide it from potential predators. When the hatchlings emerge from their nests, they use the moonlight reflected off the water to navigate their way into the surf. This is an ideal time for birds or raccoons to pluck these tiny reptiles from the beach and into their hungry mouths. Scientists are still decoding the mystery behind the synchronized hatchings, and believe that the turtles communicate with each other prior to hatching.

In 1978 the loggerhead turtle was classified as a threatened species. In 2002 the Northern and Florida Panhandle loggerhead was placed on the endangered species list, and in 2004 the amount of loggerhead nests established dropped by about 50%. Scientists suspect climate change has led to less food (like shrimp, crabs, algae) for the turtles. Female turtles nest every 2-5 years, and if there isn’t enough food, they delay nesting for an extra year. 

The decline in nests may also be attributed to the imbalance in the male and female loggerhead population. Changes in sand temperature affect the loggerhead population by altering the gender ratio. When sand temperature is greater than 29° C, most turtle hatchlings will be female. Below 29°C, most hatchlings will be male. During the summer, beaches in south Florida  get so hot that female loggerhead turtle hatchlings significantly outnumber the male hatchlings. 

There are many threats facing loggerhead turtles. Commercial fishing causes turtles to get caught in nets and drown, coastal development means fewer nesting areas, artificial beachfront lighting messes with the hatchling’s moon GPS system, mechanical raking and use of vehicles on beaches result in fewer hatchlings, heavy boat traffic adds up to turtles being struck by boat propellors, and the addition of trees or tall buildings to beachfronts signifies a change in sand temperature. These are all severely impacting turtle populations worldwide, but luckily, there are a few things you can do to help!

Keep beaches clean- pick up your trash and any trash you find lying around. Don’t disturb sea turtle nesting sites and inform others to do so as well. Avoid unnecessary night-light; the moon can handle it! Try not to release balloons into the air, especially if you’re near a coast, because sea turtles can mistake balloons for jellyfish and choke on them. And finally, volunteer with a turtle rescue, rehab, and release program and spread the word about turtle conservation! Two of my favorites are Gumbo Limbo and Loggerhead Marine Life Centre. Let’s make sure loggerheads and sea turtles alike are around for future turtle generations to come! 

Photo found here

Juvenile loggerhead turtle (Caretta caretta) released into captivity by researchers, photographed in the wild immediately after release.Taken Feb 18, 2003 off of West Palm Beach, Florida, USA. Camera: Canon EOS D60. This is by far my most famous picture (it has been Farked, has hung as a large print in the Smithsonian’s Natural History Museum for at least 18 months, and is embedded in over 20,000 websites, according to Google Image Search).