Italian
World Sea Turtle Day is celebrated today, June 16, in honor of Dr. Archie Carr, considered the father of marine turtle biology.
Sea turtles are fascinating and ancient creatures, having adapted to life in the oceans for millions of years. But do we really know them?
The species
There are 7 globally recognized species of marine turtles, all classified as threatened or critically endangered by the IUCN (International Union for Conservation of Nature).
The Loggerhead sea turtle (Caretta caretta) is the most common in the Mediterranean and the only one that regularly nests in Italy. Then there’s the Green sea turtle (Chelonia mydas), found in tropical and subtropical regions; the Leatherback sea turtle (Dermochelys coriacea), the largest of all sea turtles and the only one in the Dermochelyidae family (the other six belong to the Cheloniidae family). It does not have a hard shell like the others, but a sturdy cartilaginous carapace.
Furthermore, the Hawksbill Turtle (Eretmochelys imbricata) famous for its precious shell, unfortunately subject to illegal trade.
Then there is the Kemp’s Ridley Sea Turtle (Lepidochelys kempii), considered the rarest, the Olive Ridley Sea Turtle (Lepidochelys olivacea) known for mass nestings called “arribadas,” and the Flatback Sea Turtle (Natator depressus), mainly found in Australian waters.
Sea turtles are cosmopolitan and can be found in all the world’s oceans, from temperate to tropical waters. The Caretta caretta is particularly abundant in the Mediterranean, with major nesting sites in the eastern part (Greece, Turkey, Cyprus, Libya).
They are among the longest-living animals, with an average lifespan that can reach up to 70-80 years, and some species even more. Sexual maturity is reached between 20 and 30 years. Females return to the same beach where they were born to lay their eggs, a phenomenon still partly mysterious to scientists, believed to be linked to the Earth’s magnetic field.
Food intake
The diet of sea turtles varies depending on the species and age: the Caretta caretta are carnivorous and feed on jellyfish, fish, crustaceans, and mollusks. Many species, when they are young, feed on zooplankton, especially jellyfish. Some turtles are omnivorous or predominantly herbivorous (like the green turtle, which feeds mainly on algae and marine plants).
They are among the oldest animals on the planet, with fossils dating back over 200 million years. They are great travelers: some species cover thousands of kilometers each year. They do not have teeth, but powerful beaks adapted to their diet. The temperature of the sand at nesting sites can determine the gender of the offspring (high temperatures favor females).
The dangers
Unfortunately, all species of sea turtles are threatened and at risk of extinction due to various human activities: marine pollution, plastic, accidental capture, loss and degradation of nesting sites due to coastal urbanization, tourism, and erosion.
Furthermore, poaching and illegal trade: for meat, eggs, and shells (especially for the hawksbill turtle), climate change, the increasing global temperatures can alter the sex ratio of births and modify habitats, collisions with vessels, especially in areas of intense maritime traffic.
Their conservation is crucial for the health of marine ecosystems, and initiatives such as World Turtle Day aim to raise awareness and promote concrete actions for their protection.
