What's Driving Critically Endangered Hawksbill Turtles to Extinction?

Globally distributed throughout the tropical and subtropical waters of the Atlantic, Indian, and Pacific oceans, hawksbill turtles are critically endangered despite their wide geographic range. According to the International Union for Conservation of Nature (IUCN), their population has declined between 84% and 87% over the last three generations, and their numbers continue to follow a downward spiral.

Population

As with most sea turtle species, the exact population of hawksbills is difficult to pin down because they spend a majority of their time underwater, so estimates are often based on nesting females.

The largest nesting population of hawksbills is believed to occur near the Great Barrier Reef, where about 6,000 to 8,000 females nest annually. Another 2,000 lay their eggs on the northwest coast of Australia and another 2,000 in both the Solomon Islands and Indonesia.

The remaining significant populations are spread throughout the Republic of Seychelles, Mexico, Cuba, and Barbados, with smaller groups in Puerto Rico, the U.S. Virgin Islands, and Hawaii.

Threats

Hawksbill turtles are vulnerable to many of the same threats as other sea turtle species, such as loss of habitat, excessive hunting, fishery bycatch, coastal development, and marine pollution.

However, hawksbill turtles are particularly threatened by the illegal wildlife trade and sought after in the tropics because of their ornate shells. They’re also more vulnerable to coastal development since they nest further inland than their fellow sea turtles, as well as ocean pollution, since they spend more time near coral reefs.

Illegal Hunting

Hawksbill turtles continue to be harvested illegally for their eggs and meat, but mainly for their beautifully patterned shells. The shells, which are commonly carved into combs, jewelry, and other trinkets, have been popular since the time of Julius Caesar over 2,000 years ago.

Japanese tortoiseshell imports of over 1.3 million large hawksbills from around the world between 1950 and 1992 had some of the more significant long-lasting effects on hawksbill populations. And even today, just a couple pounds of raw shell can attract prices of more than $1,000 in Japan.

Hawksbill meat is consumed less regularly than that of other sea turtle species because the meat may contain toxins that can be lethal to humans.

A 2019 study in the journal Science Advances found that 9 million hawksbill turtles were hunted for their shells in 148 years between 1844 and 1992, over six times that of previous estimates. In 2021, a report issued by WWF, TRAFFIC, and Japan Tiger and Elephant Fund revealed that Japan customs seized over 1,240 pounds of hawksbill tortoiseshell over 71 incidents between 2000 and 2019, representing about 530 individual turtles.

Coastal Development

Rather than nesting in large groups like most sea turtle species, hawksbill females nest throughout their range in more isolated populations. Hawksbill turtles also nest higher on the beach, sometimes going as far up as coastal vegetation under trees or grass, making them more vulnerable to development.

The threats from coastal development don’t stop at pushing animals out of their native habitats; an increase of infrastructure in areas near hawksbill turtle nesting sites can lead to more light pollution, as well.

In North Western Australia, which hosts one of the largest populations of nesting hawksbill turtles on Earth, researchers identified three separate nesting areas to find that 99.8% of nesting areas were exposed to light pollution. Turtles are prone to disorientation from artificial light near nesting areas, which can affect females as well as hatchlings when they make their first journey to the sea.

Ocean Pollution and Climate Change

Although hawksbill turtles are found all around the world, individuals migrate to coral reefs as their preferred habitat, their namesake pointed beaks helping them forage for sponges, anemones, and jellyfish.

Their close tie to coral reefs entails additional stressors to the turtles when effects of climate change, such as ocean acidification, take negative tolls on their habitats. In particular, between 1997 and 2013, the mean hawksbill growth rates in the Caribbean declined by 18%, a number that researchers connected directly to warming oceans.

Fishery Bycatch

Hawksbills are routinely caught in nets of large-scale fishing operations accidentally, especially since they tend to dwell near coral reefs abundant with fish. Despite a nearly exclusive lifetime spent in the ocean, these animals still require oxygen to breathe and can often drown if unable to reach the surface in time after becoming entangled.

What We Can Do

Not only do hawksbill turtles help maintain healthy marine ecosystems by removing invasive prey from coral reef surfaces (which helps maintain high coral cover on a reef), they also have cultural and tourism value for the local residents of their range.

Protecting Habitat

Raising awareness for hawksbill turtles is the first step to establishing nesting and foraging sanctuaries to protect them, though maintaining effective enforcement of those protective laws remains a more difficult element to consider. The good news is that there are already a number of countries that have banned all exploitation of hawksbill sea turtles, their eggs, and their parts on the local level in an attempt to improve international trade enforcement.

World Wildlife Fund Australia is currently working to monitor hawksbill turtle populations that travel between Australia and Papua New Guinea in an area known as the “hawksbill highway.” Part of the Coral Sea Marine Park, one of the largest marine parks in the world, concerns about the species were raised in 2018, when the government removed large portions of “no-take” areas and replaced them with laws that allow commercial fishing and only protect the seafloor.

Fighting the Illegal Wildlife Trade

Wildlife exploitation is often driven by the demand of souvenirs and products made with animal parts. The hawksbill turtle is particularly vulnerable because of the beautiful golden brown coloration of its shell, often used to make jewelry, trinkets, sunglasses, combs, and decorative pieces. Learning to identify, avoid, and report hawksbill shell products is a key step in preventing their illegal trade.

Reducing Bycatch

Fishery bycatch is always a touchy subject in communities that rely on fishing as a source of income. Luckily, conservation groups are working to create sustainable alternatives that can benefit both the fisher and the marine environments they depend upon.

Implementing circle-shaped hooks instead of common J-shaped hooks, for example, can reduce the amount of turtle bycatch in longline fisheries. In the United States, the NOAA has worked closely with the shrimping industry to develop Turtle Excluder Devices (TEDs) that reduce the mortality of sea turtle bycatch in trawls.

Satellite telemetry is also used by hawksbill turtle researchers to track the animals and learn more about their feeding and migration patterns. The goal goes beyond scientific discovery, since satellite images can help fisheries anticipate where turtles are more likely to come into contact with their boats and gear.