Sea Turtle Encounters
Of the seven turtle species found worldwide, we are fortunate to encounter at least four here in Palm Beach and the Bahamas. JASA also feels very privileged to be part of a five year Hawksbill turtle study being conducted by Larry Wood. JASA volunteers it's time and facilities in aiding the Marine Life Center as well as Florida Atlantic University in their ongoing efforts to study sea turtles and their environment as well as assist and rehabilitate those who need a helping hand.
The loggerhead turtle is one of the most common turtles that divers are most likely to encounter in Palm Beach as well as in the Bahamas. It has a very large head, orange to brown colored shell and white to yellow underbelly and skin. It is the third largest sea turtle species growing to almost 400 pounds. The southeast coast of the US, in particular, Juno Beach, just north of West Palm Beach is one of the two largest nesting grounds for the loggerhead. The other is in the Arabian Sea.
Loggerhead hatchlings who make it out to the warm waters of the Gulfstream current spend anywhere from three to fifteen years traveling around the world until they reach a certain developmental stage. They can swim extremely long distances looking for food. Once they reach a certain size, they usually leave the deeper waters and head for shallower water where they spend the rest of their lives. You can find them near reefs, lagoons, and even wrecks, resting or foraging on different types of crustaceans like lobsters, crabs and shells.
It is believed that they don’t start to breed until they are between twenty and thirty years old. Females breed in stages on average of two to three years in which time they can lay up to one to seven nests. It can take up to 70 days for the 100 or so laid eggs to hatch, depending on the location of the nest.
Loggerhead turtles are listed as Threatened in the US and Highly Endangered in Australia where they are all but gone. They can be seen mating in the spring, nesting in the summer and hatching in the late summer and fall, right here on our beaches.
When most people think of a sea turtle, they usually refer to a green turtle, otherwise known as the “edible turtle”. The flesh is considered very tasty and other parts have been used for green turtle soup, once very popular, even here in the US. In the Cayman Islands, green turtles are raised to eat. Here in the , they are on the endangered species list.
Green turtles are the second largest turtle of the seven species, smaller only to the giant leatherback turtle. As juveniles, they have a beautiful shell. As they get older, they tend to loose the pretty rayed pattern on the back of their shell. Their head is relatively small compared to their bodies.
These turtles can grow to weigh over 500 pounds. There are several types of green turtles which all form very different populations around the world such as Hawaii, the Mediterranean and the Galapagos islands.
Again, Juno Beach is another nesting area for the green turtle. In our area we see turtles of various sizes; the smaller ones on the offshore reefs year round and the larger adults only during mating and nesting season in the spring.
Like the loggerhead, green turtle hatchlings head out to sea for two to ten years before finding a place to call home and becoming bottom dwellers. When they are small, they feed mostly on jellyfish and later turn into a vegetarian feeding on sea grass, algae and sponges.
Green turtles mature very slowly in the wild, around 20-35 years old in Florida. Once they become mature, they will migrate back to the beach they were born on to mate, just offshore. Females will lay their eggs on the same beach they were born on. Females will breed every two to four years and lay from one to nice clutches of eggs every two weeks. Green turtle nests can have over 200 eggs.
In the US, the green sea turtle is listed as threatened, except for the Florida population, which is listed as Endangered.
The Hawksbill turtle is one of the most beautiful of all turtles. Its shell has always been highly prized and used to make jewelry and other tortoiseshell items. It is one of the most commonly seen turtles in Palm Beach and the Bahamas. We have resident hawksbill turtles on many of our dive sites, as they tend to pick a reef to feed on and actually become territorial about that area.
These turtles do not grow nearly as big as the loggerhead or green turtle, weighing less than 200 pounds fully grown. They get their name from their bird like beak. This “beak” and their jagged, colorful shell easily identify them from other sea turtles. Hawksbills in our area feed almost exclusively on sponges found on the reefs; sponges that would otherwise kill fish and other turtles as they contain high levels of toxic compounds. They seem to prefer sponges with high levels of “silica” which is where they got the nickname of the “glass eaters”. It is very common to find anglerfish nearby a feeding hawksbill as they try to catch some of the crumbs.
Although hawksbill turtles live on our reefs, they do not mate or nest on our beaches. Lucky for us they are one of the most docile and easy to approach turtles.
The hawksbill turtle is listed in the US as Endangered.
The largest of the seven species of sea turtle, it is unlike all the others. Not just in size but also in body composition and habitat. Growing to over ten feet in length and weighing up to a ton, it is hard to miss. Leatherbacks have a soft, black ribbed shell designed for diving to deep depths and very large fore flippers, designed for long distance travel. They can dive to depths of over 3300 feet, putting them in a category with sperm whales and elephant seals. They feed in cold waters on jellyfish and can be found as far north as the Bering Sea and as far south as New Zealand. Atlantic leatherbacks grow to larger sizes than the Pacific leatherbacks. Their life span is unknown. They do not reside in any one area, instead staying pelagic and cruising the oceans of the world with only the females coming ashore to lay their eggs.
Females lay between four and seven clutches in eight to ten day intervals. Their eggs are the largest of all turtle eggs and the hatchlings are also larger than other turtle hatchlings. There are fewer eggs in a nest than with other species. We have seen females that return to within just a few feet of their last nest. These turtles are rare to humans since they only come to shore to nest. For this reason we are extremely fortunate to be in a leatherback nesting area. Like most turtles, they nest at night, but on a very rare occasion, they have been seen nesting during the day. That is a site to see!
Leatherback turtles are listed in the US and Australia as Endangered.
To learn more about the leatherback turtles that nest on our beaches, go to www.floridaleatherbacks.com.
We highly recommend that you visit the Juno Beach Marine Life Center the next time you’re in town. They offer turtle walks at night during the nesting season and you can go and see turtles that they are helping to rehabilitate from injuries year round. If you’re lucky you might get out on the boat with us when we help release hatchlings or a rehabilitated turtle. We are proud to be volunteers for this wonderful organization and hope you’ll swing by for a visit.
Our good friend Doug Perrine has just published one of the most complete books on sea turtles called “Sea Turtles of the world” and it can be purchased at amazon.com. It is an excellent book and we highly recommend it.