There are seven species of sea turtles in the world but only five of these species are found in the Maldives. Turtles are adored for their beauty and prized for tourism. Though unfortunately they are either vulnerable, threatened, endangered, or critically endangered.
A female green sea turtle will lay 2000 eggs in her entire lifetime, however only 2 of them will survive to adulthood. As a hatchling, sea turtles face many natural threats such as crabs, seabirds, fish, sharks and many more. However, as adults, the main threats that sea turtles face are anthropogenic. There are many different threats that humans pose to sea turtles that are contributing to the near extinction of these ancient species.
Ghost nets
Ghost nets are one of the most prominent threats to sea turtles. Although they are illegal in the Maldives, they drift down from India and Sri Lanka during high tides and strong currents predominantly from January to March. Ghost nets can entangle any sort of marine life such as rays, sharks, dolphins, whales, and turtles. We often find Olive Ridley Sea turtles entangled in ghost nets as they are an oceanic species therefore, they encounter them more often than coastal species such as the Hawksbill and Green Sea turtle.
Above: Loggerhead Sea Turtle caught in ghost net (Plastic Generation)
When sea turtles become entangled in ghost nets, it is extremely likely that they will lose one or more flippers depending on how deep the lacerations are. If a turtle has more than one amputation, they are not able to be released into the wild as they would not survive. Often when a sea turtle becomes entangled in a ghost net, they may develop buoyancy syndrome. Buoyancy syndrome occurs when the turtle hyperventilates due to stress, resulting in little tears in their lungs where the air escapes and fills up their body cavity.
Above: (left) Olga, Olive Ridley Sea Turtle, with one amputation & buoyancy syndrome. (Right) Tom, Olive Ridley Sea Turtle, with two amputations & buoyancy syndrome.
Climate change
Climate change heavily affects the reproduction of sea turtles. If the temperature of the nest is too hot it will produce mainly females, and if the nest is too cold it will produce mainly males. There needs to be an equal ratio of hot and cold temperatures so that both sexes are produced so that they can continue to reproduce. Sea level rise and more intense storms will cause inundation of nests and beach erosion, resulting in the loss of nesting beaches for female sea turtles.
Plastic pollution
Plastics and micro-plastics pose a major threat to marine life but specifically sea turtles. All species of sea turtles eat jellyfish, unfortunately they often mistake plastic bags for jellyfish. Once they have eaten a fair amount of plastic, they get the feeling that they are full and therefore don’t eat anything of nutritional value, causing them to die of starvation. As well as this, trash found on nesting beaches will negatively impact hatchlings as they are likely to get caught in the debris as they try to make their way into the ocean.
Above: Green Sea Turtle eating a plastic bag (Troy Mayne, WWF).
Oil spills
As sea turtle are reptiles, they come up to the surface to breathe air every so often depending on the level of activity. When resting they can hold their breath for up to 4-6 hours, or 45min-1hour during routine activity. When they come to the surface in or near an oil spill, they inhale toxic fumes. These fumes can irritate the mucus membranes around their eyes and mouth, and even internally in their respiratory system. Ingested oil can disrupt the breathing and heart function of sea turtles, impacting their ability to dive, feed, mate, and escape predators.
Above: Kemp's Ridley Sea Turtle covered in oil (NOAA Fisheries)
How you can help
These are just a few threats that sea turtles face as a result of human interference. There are many things that people can do to reduce their impact on sea turtles.
Be a conscious consumer: eat sustainably, ask where and how your seafood was caught, buy less single use plastic, use a reusable water bottle, and take your own shopping bag when buying groceries.
Conduct local beach cleans.
Be an eco-tourist: reduce disturbance and don’t use lights on nesting beaches, fill in holes and knock down sandcastles before you leave the beach.
Spread awareness: about the threats that sea turtles face and how others can help.