Sea turtles face many dangers, which have led to several species becoming endangered. There are seven species of sea turtles that still live today. Six of these belong to the family Cheloniidae, and one belongs to the family Dermochelyidae. All of these species are listed on the IUCN Red List, which shows how endangered they are. The list includes six species as "threatened," two as "critically endangered," one as "endangered," and three as "vulnerable." The flatback sea turtle is listed as "data deficient," meaning there is not enough information to determine its conservation status. Sea turtles typically lay about 100 eggs at a time, but only one of these eggs usually survives to become an adult. Many dangers to hatchlings are natural, such as predators like sharks, raccoons, foxes, and seagulls. However, new dangers to sea turtles are caused by humans.

Artificial lighting

Artificial lights can harm adult and young sea turtles. Sea turtles use the brightest part of the horizon to find their way back to the ocean. This brightness comes from natural lights, such as the moon and stars, reflecting off the water. However, as people build more structures near the coast, artificial lights are becoming more common. These human-made lights are often brighter than natural lights, which can trick sea turtles into moving toward them instead of the ocean. When a sea turtle moves away from the ocean, it is called a disorientation event. These events increase the chances of the turtle being eaten by predators, becoming too tired, losing too much water, or getting hurt. Many disorientation events are deadly. Any light that a turtle can see from the beach, whether directly or indirectly, can cause a disorientation event. Brightly lit beaches may also cause adult sea turtles to perform a false crawl. This happens when a female turtle decides the beach is not a good place to lay her eggs and returns to the water. False crawls make adult turtles very tired and may cause them to release their eggs into the ocean, which is deadly for all the eggs.

As people have learned how artificial lights harm sea turtles, groups that protect marine life and conservation organizations have started large efforts to help. Communities near beaches have been informed about how too much lighting affects sea turtles. Many places have tried to make beaches darker and replace harmful lights with ones that are safer for turtles. Coastal areas have also created or updated rules about lighting to help protect sea turtles. These rules let local governments ensure that lights used near beaches are safer for turtles.

Magnetic interference

Ferrous metal wire mesh screens are often used to protect sea turtle nests from predators digging up and eating the eggs and young turtles. A new worry is that the magnetic fields created by these steel mesh cages might interfere with the developing magnetic sense of baby turtles. Scientists may not know the full effects of using steel mesh cages for many years, as they need to observe how well the first adult turtles that grow up in these cages reproduce and return to the beach to lay eggs. Pregnant turtles or their young may also be affected by magnetic fields from power lines, pieces of iron, steel seawalls, or other human activities that change Earth's natural magnetic field in certain areas.

Oil spills and marine pollution

Marine pollution harms sea turtles both directly and indirectly by damaging their natural habitats. Dangerous ocean pollutants include toxic metals, PCBs, fertilizers, untreated waste, chemicals, and petroleum products. Oil spills are especially harmful to sea turtles. While oil does not stick to sea turtles as easily as it does to other marine animals, they still face risks when they surface for air. Oil can enter their eyes, skin, and lungs, causing serious health problems. Even if sea turtles are not directly exposed to pollution, they can still eat harmful chemicals through their food. Oil also harms seagrass, a key food source for green turtles. The diets of hawksbill, loggerhead, and Kemp’s ridley sea turtles are affected because oil reduces the numbers of sponges and invertebrates they rely on. Prolonged exposure to pollution weakens sea turtles, making them more vulnerable to other dangers.

According to the Sea Turtle Conservancy, formerly the Caribbean Conservation Program, sea turtles are exposed to marine pollution at every stage of their lives, including as eggs, hatchlings, juveniles, subadults, or nesting adults. A 1994 study along Florida’s Atlantic coast found that 63% of hatchlings had swallowed tar. Loggerhead turtles are especially affected by tarball ingestion, which can cause swelling in the throat, leading to serious issues with buoyancy and internal organs. Areas with heavy oil activity, such as the Gulf of Mexico, the Caribbean, and the coasts of Texas and Florida, are also important sea turtle habitats. Sea turtles in these regions are not the only ones at risk because ocean currents can carry pollution far from its source.

Breeding season is a dangerous time for sea turtles because pollution can contaminate beach nesting sites. Contaminated food can harm digestion and damage the digestive tracts of sea turtles. Female sea turtles may avoid nesting areas if they fear oily conditions. If they do lay eggs, the eggs may be harmed by oil in the sand or contamination from the mother turtle. If oil contacts eggs during the final half of their development, the survival rate of hatchlings drops sharply. Hatchlings that survive are more likely to have physical deformities.

Ocean plastic

Every year, eight million tons of plastic enter the ocean. For many sea animals, such as sea turtles, plastic in the ocean can cause serious problems. Plastic bags floating in the water look like jellyfish, which sea turtles often eat. If a sea turtle eats a plastic bag, it can block its stomach and intestines, which may lead to the turtle's death. Scientists have found plastic and other trash inside the stomachs and intestines of sea turtles during examinations. Plastic waste has caused the deaths of all types of sea turtles. Sea turtles have also been found with plastic straws in their noses, plastic bags or toothbrushes in their stomachs, or fish hooks stuck on their flippers. Plastic straws can be dangerous because sea turtles may mistake them for food. This can cause the turtles to choke or stop eating, even though their stomachs are full of plastic. Although small, plastic straws are among the most common items polluting the ocean. As mentioned earlier, sea turtles are more likely to eat plastic if it looks like their usual food. Studies show that if a sea turtle eats more than 14 pieces of plastic, it has a 50% chance of dying.

Tourism

Because many sea turtle species are popular, people often visit places where the turtles live or nest to watch and take pictures of them. This has caused many turtles to die due to boat accidents, tourists trying to catch or take turtles, and other problems. In Costa Rica, tourists have been criticized for disturbing the nesting of olive ridley sea turtles that live there. These tourists confuse the turtles by trying to take selfies with them. Baby turtle release events often happen during the day in different areas, which makes it easier for predators to find and eat the young turtles. [3]

Boats

Sea turtles face many dangers from boats, such as oil spills, damaged habitats, and collisions with vessels. Boat strikes cause two types of injuries: blunt force trauma and propeller cuts on the turtle's shell. Blunt force trauma happens when the boat's hull hits the turtle, causing cracks that are not easily seen on the shell. Propeller injuries create clear, parallel lines on the shell. If these wounds are deep, they can damage the turtle's spinal cord or lungs, which are located on the top part of the body under the shell. Scientists use data from sea turtles that wash up on shore to measure how often boat strikes happen. This data increased by 20% in Florida between 1985 and 2005. Sea turtles often cannot avoid boats moving too fast, and faster speeds cause more serious injuries. When sea turtles surface to breathe, they swim just below the water's surface, taking short breaths before diving deeper to hunt. This depth is where boat propellers are most likely to hit turtles, making it harder for boaters to see them.

To reduce harm, speed limits in certain areas have helped protect species like the Florida manatee. These limits would be especially important in shallow, coastal areas near nesting beaches during nesting seasons. Boats can also be modified to lessen their impact on marine life. Jet drive motors use an impeller instead of a traditional propeller, reducing the risk of injury. These motors are positioned close to the boat's hull, making it less likely to hit turtles that are not surfacing. Propeller guards may help slightly when boats move slowly, but they are not effective at higher speeds.

Sea turtles that wash ashore with boat-related injuries can sometimes be treated at rehabilitation centers. While treatment is not always successful, some turtles survive these injuries.

Fishing

A study published in Conservation Letters found that more than 8 million sea turtles died between 1990 and 2010 because of injuries caused by being accidentally caught in fishing nets. Fishers often use large nets and hook systems that catch any animal that swims near them, including sea turtles, dolphins, and sharks. This accidental catching of non-target animals is called "bycatch," and it is a major cause of sea turtle deaths, as seen in Baja California. Three fishing methods—longline, trawl, and gillnet—cause the most sea turtle accidents. Many turtles die from drowning after becoming trapped in nets and unable to reach the surface for air. Another common danger occurs when turtles swallow sharp hooks, which can damage their throat, stomach, or internal organs.

Poaching

In many countries, sea turtles are caught, killed, and sold for their meat, shells, and leather flippers. Their eggs are often stolen for people to eat, and some cultures consider them a special food. In other cultures, people believe eating sea turtle eggs helps with romantic feelings or can help people live longer. On some islands, parts of sea turtles are used in religious ceremonies and are treated as sacred. Sometimes, the bodies of sea turtles are turned into jewelry, musical instruments, souvenirs, sunglasses, or wall decorations. Hawksbill sea turtles are especially targeted because their shells have beautiful patterns.

Global warming

Global warming is believed to have serious effects on wildlife in the coming decades. Evidence shows that sea turtles have already been impacted. As temperatures rise, ice in polar regions is melting, causing sea levels to increase. This rise in sea levels has led to the loss of beaches, which are important nesting areas for sea turtles. Global warming is linked to severe weather, which can create strong and frequent storms that erode beaches and flood turtle nests. As Earth's temperature increases, the temperature of sand on beaches also rises, which can lower the survival rate of baby turtles. The sand's temperature also influences the gender of hatchlings, as higher temperatures tend to produce more female turtles. Changes in climate affect ocean currents and alter the number and location of prey species. Water that is too warm can cause coral bleaching, which harms coral reefs that are vital for certain species, such as the hawksbill sea turtle.

Disease

A disease called fibropapillomatosis causes external tumors in turtles. These tumors can grow very large, making it hard for sea turtles to see, eat, or swim, which can lead to their death. For unknown reasons, most cases of fibropapillomatosis have been found in green sea turtles (Chelonia mydas), but none have been found in leatherback sea turtles (Dermochelys coriacea). This disease has been found in all the world's major oceans. Although the exact cause is unknown, many scientists think it is caused by a virus. The tumors can be smooth or have sharp points and can be red, pink, gray, black, or purple in color. These tumors usually appear on the soft skin of the sea turtle, such as the neck, eyes, or bottom of the flippers. They can be as small as a pea or as large as a grapefruit.

Conservation efforts and rehabilitation centers

A study by Discovery News found that the Mediterranean, the Eastern Pacific, the Southwest Atlantic, and the Northwest Atlantic are the regions most in need of protection efforts. In 1963, the Marine Turtle Group was formed by the chairman of the Survival Service Commission of the International Union for the Conservation of Nature and Natural Resources. This group was the first international place for research and conservation of sea turtles. In the United States, the Endangered Species Act of 1973 was passed in 1973 to protect all sea turtle species. In 1977, a Memorandum of Understanding was signed between NOAA Fisheries and the U.S. Fish and Wildlife Service (USFWS) to enforce the ESA for sea turtles. USFWS is responsible for protecting sea turtles on nesting beaches, while NOAA Fisheries focuses on protecting sea turtles in the ocean. International sea turtle conservation has been guided by two major agreements: the Indian Ocean–South-East Asian Marine Turtle Memorandum of Understanding and the Inter-American Convention for the Protection and Conservation of Sea Turtles. To reduce the number of turtles killed by fishing, new turtle-safe fishing tools have been introduced, such as circle hooks, fish bait, and turtle excluder devices. Poaching has been banned in most countries, and turtle conservation education has grown in both size and effectiveness.

Rehabilitation centers have also been created, such as the Marine Life Center in Juno Beach, Florida, and the Karen Beasley Sea Turtle Rescue and Rehabilitation Center on Topsail Island, North Carolina. These centers help protect sea turtles by: a) rescuing sick or injured turtles and taking them to treatment, b) treating and/or operating on the turtles, and c) releasing them back into the ocean after they recover. Some turtles have injuries too severe to survive outside the centers, but hundreds of turtles treated at the Gordon and Patricia Gray Veterinary Hospital in Juno Beach and the Sea Turtle Hospital in Topsail Island have been successfully released over the past few decades.

Watamu Marine National Park in Kenya is another example of successful sea turtle conservation. Through a 20-year nest monitoring program and protection efforts, the Watamu program increased the number of nests during nesting seasons by 50% and improved hatching success. Strategies included patrolling nests to stop illegal egg collection and moving nests from areas at risk due to tourism. Although illegal collection of adult turtles and eggs remains a problem, protective laws and conservation actions have improved long-term outcomes along the east coast of Africa, where five of the seven sea turtle species nest.

Conservation programs show the importance of involving people who directly affect sea turtles. Combining nest management, protective laws, and community involvement has improved nesting success and increased the chances of young turtles surviving after hatching. More conservation and management efforts will be important for the long-term survival of sea turtles.

However, it is hard to evaluate the progress of conservation programs because many sea turtle populations have not been studied enough. Most information about sea turtles comes from counting nests on beaches, but this does not give a complete picture of the entire population. A 2010 report by the United States National Research Council stated that more detailed information about sea turtles’ life cycles, such as birth rates and death rates, is needed.