Sea Turtle Facts | Florida Wildlife Guide
Although they are air-breathing reptiles, they are wonderfully adapted to life at sea. After hatching and making their way into the ocean, male sea turtles never again set flipper on land. The females only come ashore to give birth every one to nine years depending on the species. Their long flippers and streamlined shapes allow them to move gracefully through the water, unlike their laborious movements on the beach. They migrate thousands of miles over their 50-year lifetimes and can stay submerged for hours at a time. Despite being born on land, they are truly creatures of the sea.
The loggerhead (Caretta caretta) is the most common sea turtle in Florida. It can be recognized by its blocky head. These turtles weigh, on average, about 250 pounds and their carapace can be 3 feet long. It swims at a leisurely pace, hunting shelled prey like clams and crabs. There are only two major nesting sites for loggerheads in the world, one of which is the Atlantic coast of the southern United States. Most of those nest sites are in South Florida, where there can be aggregations of more than 10,000 breeding females!
While it would seem that the endangered green sea turtle (Chelonia mydas) gets its name from the coloration on its body, it actually derives from the green body fat that exists under the carapace, known as “calipee.” In the late 1800s, Key West was a hub for the sea turtle trade, shipping 15,000 turtles per year to England. Green turtles can weigh over 350 pounds and are the only sea turtles that are primarily vegetarian. Florida’s beaches host up to 1,000 green sea turtle nests each summer.
Leatherbacks (Dermochelys coriacea) are by far the largest of Florida’s sea turtles, growing to weigh as much as 2,000 pounds and reaching a length of 6 feet or more. Instead of having a hard shell like other turtles, these beasts have firm, leathery skin protecting their bodies which are terraced with seven ridges running lengthwise down their backs. They feast on massive quantities of jellyfish, aided by stiff spines in their jaws and throats to trap their slippery prey. They are able to dive to 3,000 feet and can survive in cold waters as far north as Alaska and Labrador. Approximately 30 – 60 nest in Florida each year.
The critically endangered Kemp’s ridley sea turtle (Lepidochelys kempi) is the rarest and smallest marine turtle in the world, barely exceeding 2 feet in length and rarely weighing more than 100 pounds. They are the only turtle to practice “arribada” nesting, which is a synchronized, mass nesting event. Their primary nest site is a single beach in Rancho Nuevo, Mexico. In the mid-1940s, a mass nesting was filmed at that beach that showed approximately 42,000 females coming ashore to lay eggs on a single day. By the mid-1980s, a typical breeding season would draw 250 females to that same beach. Their total global population is currently estimated to be 7 – 9,000 adults and, surprisingly, they are commonly found swimming near the shorelines in southwestern Florida.
The hawksbill turtle (Eretmochelys imbricata) is also critically endangered, due to their reliance on a diet of sponges and sea anemones found on coral reefs. Their fate is therefore tied to our ability to protect coral reef habitats in waters throughout the tropics which are subject to damage from commercial fishing and coral bleaching due to climate change. Their beautiful shell also made them a target of extensive hunting in the past and in some regions today, as they were the source of many “tortoise shell” products. In the continental United States, their only nesting sites are on southern Florida beaches. They weigh between 100 and 200 pounds and can be 3 feet long. The shell has overlapping scales of armor and the rear of the carapace is serrated.
All seven species of sea turtles around the world are subject to similar threats. Many are still hunted for their meat, and their eggs are considered a delicacy in many countries around the world. Thousands are entangled in fishing nets every year, and many starve when their stomachs are filled with plastic bags that resemble jellyfish when they are floating in the ocean. They lose nesting sites when beaches get washed away or developed and drag nets from shrimping operations can scrape their food sources and coral habitats from the sea floor.
In recognition of these threats, many global efforts are in place to restore sea turtle populations such as “turtle excluder devices” in shrimp nets and regulations on beach development. Many residences and hotels along beaches have also agreed to turn off or block lights at night which can confuse young turtles. As a result of these efforts, Florida beaches have seen recent increases in green sea turtle nests and Kemp’s ridleys have also increases since the turtle-friendly nets were introduced to Florida’s commercial shrimping industry.