sea turtles

Sea turtles have lived on our planet for more than 100 million years. There are seven species of marine turtle, six of which are threatened with extinction and included on the IUCN Red List (hawksbill, loggerhead, leatherback, Olive ridley, green and Kemp’s ridley), for the seventh (flatback) we simply don’t have enough information to establish whether they are also in such a precarious state.

From the moment they hatch until adulthood, turtles are fighting against the odds: estimates put their survival rate at just one in 1,000-10,000. As the hatchlings scrabble out of their eggs and up through the sand onto the beach, birds, racoons, wild dogs and even crabs are waiting for them, if they make it to the water, birds and fish are ready to feast upon them. Those which do make it out to open water face a variety of threats, from predators like sharks and dolphins to chemical, oil and plastic pollution, in particular ghost gear, perhaps the greatest threat of all.

They spend their lives at sea, swimming, diving and sleeping. They can hold their breath for 4 to 7 hours at a time, allowing them to dive deep into the ocean for food (some go down to around 300 metres for food). They travel enormous distances, sometimes covering up to 20 miles a day, as far as from Indonesia to the west coast of America.

Marine turtles take between 20 and 30 years to reach sexual maturity. Females may nest every 2 or 3 years, laying around 2,000 eggs within a lifetime. When ready to nest, female turtles return to the beach where they were born. The turtles’ sensitivity to the Earth's magnetic fields allows them to return to the beach, despite not having been there for 2 to 3 decades. The hatchling’s sex is determined by its nesting environment, the warmer it is, the higher the ratio of females to males - climate change is having a direct effect on the male/female ratio.

Threats to sea turtles

• fisheries bycatch: the fishing industry contributes to the death of thousands to tens of thousands of sea turtles each year, turtles become trapped in longlines, gill nets and trawls are thrown away as bycatch; Getting accidentally caught in fishing gear is probably the biggest threat to marine turtles. It’s also estimated that more than 50% of marine turtles have ingested plastic or other human rubbish - often mistaking it for food such as jellyfish. Plastic washed up on beaches can also limit space for nesting and block tiny hatchlings’ paths to the ocean.  

• pollution: plastic pollution, ghost gear, and other debris can injure or kill sea turtles through ingestion or entanglement;

• coastal development: sea turtle habitats are destroyed as urban development, increases in sea traffic and sea dredging encroach on both nesting and feeding grounds;

• direct take: human consumption of sea turtle eggs and meat and the use of turtle shells for jewellery and handicrafts, while banned in some areas of the world, still pose a threat; and

• climate change: global warming has a direct impact on both sea turtle populations and their habitats. Climate change can increase sand temperature (higher temperatures produce more females than males, skewing sex ratios), cause sea level rise (which can flood nests), and can mean an increase in storm events, which will affect hatchling survival.

spotlight on the Oceanic Society

Oceanic Society is one of the oldest NGOs working in ocean conservation, aiming to raise awareness of the ocean by combining tourism with science, exploration, and conservation on ship-based expeditions. According to their website, one of their main objectives is the conservation and protection of the seven sea turtle species. The programmes they run to support sea turtles also address many of the challenges faced by the ocean today such as unsustainable fishing, marine pollution or climate change and aim to protect habitats like coral reefs, mangroves and seagrass beds.

Oceanic Society is involved in two main programmes for sea turtle conservation: the State of the World's Sea Turtles (SWOT) and the Marine Turtle Specialist Group.

SWOT is a partnership of Oceanic Society, the IUCN-SSC Marine Turtle Specialist Group, Duke University's OBIS-SEAMAP, and an international network of institutions and individuals. The SWOT Team compiles and publishes global sea turtle data that supports conservation and management efforts at the international, national, and local scales, maintaining the publicly available SWOT database and publishing an annual report on the State of the World's Sea Turtles.

Oceanic Society also co-manages the IUCN-SSC Marine Turtle Specialist Group, a volunteer network of more than 300 sea turtle experts in over 80 countries, which was founded in 1966 as part of IUCN's Species Survival Commission, and is now considered the world authority on sea turtles. The group's primary responsibility is to regularly assess the global risk of extinction for each of the seven species of sea turtles using IUCN Red List criteria. 

what can I do?

• support sea turtles by adopting one from the WWF or protecting nesting beaches around the world by supporting see turtles’ Billion Baby Turtles project

• support sustainable tourist resorts with turtle conservation projects

• refuse sea turtle eggs and meat

• avoid buying anything using turtle shells for jewellery and handicrafts

• volunteer to help protect sea turtles

dive in deeper

State of the World's Sea Turtles—SWOT Report XVIII - 2023

WWF: Top Ten Facts about Marine Turtles

Smithosian Institution: Sea Turtles