Olive ridley turtle -- Sea turtle populations around the world are under increasing threat from factors such as coastal development, overfishing and bycatch (when turtles are caught unintentionally during fishing for other species). The olive ridley -- the most abundant sea turtle species -- is also at risk of wildlife crime, with its eggs smuggled to cities where they are eaten as a delicacy in restaurants and bars.
Hal Brindley
Olive ridley turtle -- Listed as vulnerable by the International Union for Conservation of Nature (IUCN), olive ridleys live and nest throughout the tropics, but have been found in temperate regions as far south as New Zealand and as far north as Alaska.
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Olive ridley turtle -- When they are ready to lay their eggs, they descend upon the shore to dig deep chambers in the sand where they bury a clutch of often more than 100. This makes them an easy target for poachers.
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Olive ridley turtle -- Paso Pacifico, a conservation organization working in Central America, estimates that poachers in the region destroy more than 90% of sea turtle nests to sell the eggs into the illegal wildlife trade. To trace trafficking routes, it developed decoy eggs with a GPS system that can be placed in real nests to fool poachers.
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Olive ridley turtle -- The decoy eggs can be used to strengthen law enforcement, helping to combat trafficking and protect sea turtle populations.
Paso Pacifico
Green turtle -- Green turtles are classed as endangered by the IUCN, which considers the harvesting of eggs and adults from nesting beaches as the biggest threat to their future.
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Green turtle -- It's thought there used to be as many as 500 million green turtles in the Caribbean alone. However, the species was at one time eaten by European explorers and later used for turtle soup.
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Green turtle -- Paso Pacifico's decoys are also used to track the trade of green turtle eggs, since they are a similar shape and size to those of olive ridleys.
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Loggerhead turtle -- The IUCN listed loggerheads as vulnerable in 2015 -- an upgrade compared to their "endangered" classification in the 1990s. However, improvements in a species' status can reflect both genuine population growth and better data.
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Loggerhead turtle -- Fisheries bycatch was classified as the biggest threat to loggerheads globally, followed by coastal development and human consumption of eggs and meat.
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Loggerhead turtle -- Loggerhead turtles typically nest in tropical and sub-tropical regions of the world, laying up to 120 eggs in two to five clutches every two to four years. Florida, the Brazilian coast and the Eastern Mediterranean are particularly popular nesting spots. They are known for their long migrations -- in 1996, a female named Adelita was tracked crossing the Northern Pacific, from Mexico to near Japan.
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Leatherback turtle -- Once considered critically endangered, leatherbacks are now listed as vulnerable by the IUCN. SWOT (The State of the World's Sea Turtles -- a series of reports compiled by the Oceanic Society) states numbers are rapidly declining in many parts of the world.
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Leatherback turtle --The leatherback's shell is covered with a thick leathery skin, with grey hues as adults, and ridges along their back that distinguish them from other sea turtle species. There's a reason for these differences -- leatherbacks are part of a different family, "Dermochelyidae." In fact, they're the only member still alive today.
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Hawksbill turtle -- The hawksbill exists throughout the world's oceans but was listed as critically endangered by the IUCN Red List of species in 2008 (its last assessment). Its shell has historically been used for jewelry, and though international trade of tortoiseshell is prohibited, it still occurs.
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Hawksbill turtle -- The World Wide Fund for Nature lists loss of nesting and feeding habitats, egg poaching, fishery-related mortality, pollution and coastal development among the threats hawksbills face. SWOT says hawksbills in the Eastern Pacific are "probably the most endangered sea turtle population in the world."
Stuart Price
Hawksbill turtle -- Named for its sharp beak, the hawksbill is the only marine consumer with a diet predominately made up of reef sponges, according to SWOT. Hatchlings weigh a mere five grams, while fully-grown adults can weigh up to 150 kilograms.
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Kemp's ridley turtle -- Last assessed by the IUCN in 2019, the Kemp's ridley is critically endangered, with just over 22,000 adults thought to be in existence. It nearly went extinct 50 years ago according to SWOT, which says the species has shown signs of recovery despite myriad threats.
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Kemp's ridley turtle -- The Kemp's ridley is known for its limited range. It spends most of its time around the Gulf of Mexico, Caribbean and eastern coast of the US, although it has been found across the North Atlantic.
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Kemp's ridley turtle -- It's the smallest sea turtle, growing up to 70cm and 60 kilograms, and taking 10-15 years to reach sexual maturity. Along with olive ridleys, it is the only sea turtle to exhibit mass nesting.
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Flatback turtle -- Flatback turtles have only existed since 1988 -- that is, according to science. Once considered a type of green turtle, they were formally described as a separate species in the late '80s.
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Flatback turtle -- Flatback turtles nest only along Australia's northern coast and live in the ocean between Australia, Papua New Guinea and southern Indonesia. They can stay active underwater longer than most other sea turtles.
