Friday, April 19, 2013

Rescue and Research Facilities for Sea Turtles
Many sea turtles end up at rescue and rehab facilities because they are injured or sick. At these facilities the animals are treated and if possible released back into their native habitat. The turtles are treated for injuries to their flippers caused by predation, fishing line and trap rope entanglements, and often end up in amputation of the affected appendages.The shell can also be damaged by collisions with boats. Some animals are being treated for intestinal implications, like ingesting plastic bags, balloons, and fishing lines and hooks. In South Florida many turtles undergo surgery for removal of viral tumors (follow Fitzy's story at
Turtle Hospital in Marathon, Fl
http://www.turtlehospital.org/blog/). Besides rehabilitation and rescue these facilities offer field trips, education and some provide opportunities for adoption of animals, as well as for internships and volunteer work.

There are several rescue and rehabilitation facilities around the world, but here are a few of them.

Sea Turtle Inc is located in South Padre Island Texas and is primarily involved with the Kemp's Ridley turtles, but has other turtles as permanent residents like Allison, an Atlantic Green turtle that lost three of her flippers and now swims with prosthetic flippers. MJ   the loggerhead lost all four of his flippers in a shark attack and Hang10, a Kemp's Riddley with a genetic birth defect and now travels to local events and schools  to educate people.
http://www.seaturtleinc.org/



 The Turtle Hospital in Marathon, Florida, who has Fitzy amongst other turtles in need of rescuing. The photo to the right, courtesy of turtlehospital.org, shows the tumors all over Fitzy, who is now cancer free.
 http://www.turtlehospital.org/blog/


The South Carolina Aquarium offers help for the sea turtles as well.
For more information on adoption, nest conservation, current residents and pictures please go to the websites listed below.
http://scaquarium.org/STR/


Allison @ seaturtleinc.   

Migration and Navigation of the Loggerhead turtle
 Loggerheads travel thousands of miles across the Atlantic Ocean to the  circular current systems called gyres that serve as open ocean nurseries, where they stay for several years to mature. The male turtles will then migrate to their foraging areas, while the females eventually will return near their birth place to lay their eggs.
Sea turtles are using the earths magnetic field , the sun, and skylight polarization to navigate across the oceans and find specific destinations, as well as to return to the beach where they were hatched. They calibrate their built in "compass" to the horizon when they are first born and utilize the oceans waves to guide them several miles out to sea after they first enter the water. Since these turtles are sensitive to small differences in field inclination and intensity (Lohman, 1996) they can use the fields that exist at specific locations to help them navigate.
They also use those fields as markers along their journey, and detect errors in the course by changes in the angle of the magnetic field.
Metal cages are often placed over the nests to protect the eggs from predators like dogs, foxes, and especially racoons. However, some studies seem to indicate that the metal in those cages disrupts the
photo courtesy by sciencedirect.com
calibration of the turtles to the magnetic field. One option to resolve that issue is to construct cages made of non magnetic material. The lights from hotels and streets near nesting beaches can also distort the hatchlings, as they try to find their way towards the ocean, and take them inland instead. Having dimmed or no lights during hatching season can help the little turtles with their journey.
 www.nature.com/nature

Sources
Geomagnetic map used in sea-turtle navigation, by K. Lohmann, Nature|Vol 428|29 April 2004|
www.nature.com/nature
Magnetic field distortion produced by protective cages around sea turtle nests, by Irwin, Horner,Lohmann Biological Conservation 118 (2004) 117-120

Sunday, April 14, 2013

...And meet their Smaller Cousins

The Hawksbill Turtle (Eretmochelys imbricala)
courtesy of hawksbillseaturtle.org

This turtle is named after its narrow head  with its bill like beak. An adult grows between 2 to 3 feet long and weighs between 100 to 200 lbs. It has a brightly colored carapace with overlapping scutes, while all the other sea turtles have non overlapping scutes.





Olive Ridley  (Lepidochelys olivacea)
It is named after its pale green carapace. It grows between 2 to 2.5 feet long and weighs between 75 to 100 lbs. It has 6 or more scutes on it's shell, and is one of the most abundant of the turtles.

 (photo courtesy of aquariumofpacific.org)



Kemp's Ridley (Lepidochelys kempii)

 Richard Kemp discovered these turtles in 1880, and the animals were named after him. They are the smallest of the sea turtles growing only to 2 feet, and between 75 to 100 lbs. Their carapace is wider than it is long, and has an olive gray color. The head is triangular shaped with a hooked beak. This is the only species that primarily nests during the day. These turtles are currently listed as critically endangered.
http://www.seaturtleinc.org
Meet some of the Larger Turtles

The Leatherback Turtle (Demochelys coriacea)

photo courtesy of library.thinkquest.org

It is the largest of all the sea turtles, between 4 to 8 feet long, and weighs between 500 and 2000 lbs. It has a smooth, leathery, flexible carapace (shell), and is the only sea turtle with no scutes (scales). It is the only one of the species that has longitudinal ridges down the carapace. The shell is black with gray, white or pink spots. These animals have the furthest migration route of all the sea turtles, traveling about 10000 miles a year from Asia to the West Coast of the USA. The Leatherbacks are currently listed as critical endangered, and are at risk to be extinct in the next 20 years.

photo courtesy of virginiaherpetological society.com


Green Turtle (Chelonia mydas)
photo courtesy of conserveturtles.org
It is the largest of the hard shelled sea turtles, reaching a length up to 4 feet and weighing up to 500 lbs.Their carapace is olive brown to almost black and has 4 pairs of scutes (scales). It also travels thousands of miles in search for food. It is currently listed as endangered.





The Loggerhead Turtle (Caretta caretta)
it is named for its massive head and jaws, grows up to 4 feet long and weighs between 200 to 400 lbs. It is reddish brown with a slightly heart shaped carapace. More detail about this turtle can be found through out this blog site.





The Flatback Turtle(Natator depressus)
courtesy of marinebio.org

courtesy of seeturtles.org
Got it's name for it's flat carapace, which is colored pale, grayish green. It has 4 pair of scutes in it's shell, and the edges of the carapace are distinctly up turned. It grows up to 3 feet long and weighs up to 200 lbs. They are only found around Northern Australia and Southern Indonesia.

The photo on the left shows the carapace with the scales, typical for the Flatback sea turtles.

Most of this information was obtained from http:www.seeturtles.org/1893/sea-turtle-identification.htlm
seeturtles.org/