Conservation Isn’t Just Saving Beaches: This Turtle Study Says Reefs and Routes Matter Too

Three species of sea turtles are regularly observed in the Red Sea, which is an inlet of the Indian Ocean: hawksbills, greens, and loggerheads. A set of islands off the coast of Saudi Arabia provides nesting habitat for both the hawksbills (Eretmochelys imbricata), which are classified as Critically Endangered, and greens (Chelonia mydas), which are doing relatively well, according to the IUCN Red List assessment. The turtles come up to nest on several of the 39 islands in the archipelago, favoring those that are always above sea level.

A Saudi development project—NEOM—whose goal is “to support the diversification of the Kingdom’s economy and deliver urban solutions so that people and planet can thrive in harmony,” plans to create sustainable human communities in the northeastern Red Sea coastal region, which includes the island nesting beaches. An envisioned “NEOM Nature Reserve” promises to ensure conservation of its nature, including sea turtles.

To date, most research on these turtle species in the Red Sea has focused on their nesting habitats, with limited understanding of their whereabouts between nesting events. Yet, their migratory paths and inter-nesting areas may be key to long-term survival. Since sea turtles can’t feed on land, their nutrition depends on finding suitable ocean feeding grounds, such as seagrass beds. Coastal waters are subject to many human impacts from activities such as offshore mining, commercial fishing, shipping, and recreation.

A recent study published in Scientific Reports looked at where female sea turtles go after they lay eggs on the Red Sea islands. Researchers from King Abdullah University of Science and Technology (KAUST) collaborated with NEOM Nature Reserve planning staff to track 17 female turtles (six greens and 11 hawksbills) during the 2022 and 2023 nesting seasons. Turtles were found either nesting or resting near shore and fitted with satellite tags designed to follow their movements on land and at the ocean surface. The green turtles were found at Walah Island, while the hawksbills were found at several islands—Shushah, Walah, and Delajala.

The satellite data were plotted to map out the turtles’ nesting, inter-nesting, and foraging areas. Between nesting events, green turtles traveled as little as 21.6 miles and as far as 312 miles within the Red Sea to forage. Hawksbills foraged from 84 miles to 150 miles from their nesting sites. Researchers identified six distinct foraging areas in the Red Sea: four in Saudi Arabian waters used by both green and hawksbill turtles, and two in Egyptian waters used by green turtles. Sea turtles are, of course, oblivious to political boundaries, but conservation programs are not. A coordinated international effort is needed to protect the Red Sea foraging areas, which include reef ecosystems.

“What stood out most was the scale of the travels that some of the hawksbill turtles made after nesting. While these turtles lay their eggs on relatively small islands in the NEOM region of Saudi Arabia, several individuals traveled hundreds of kilometers across the Red Sea to reach their feeding areas,” says lead study author and KAUST Senior Marine Megafauna Specialist Hector Barrios-Garrido in an email.

The study found that hawksbills have broader home ranges, varying from about two to seven square miles. These large areas increase the likelihood that turtles will encounter human activities such as boating, fishing, and snorkeling. The researchers, therefore, make a case for a more extensive conservation strategy that includes both the island nesting beaches (which account for 95% of sea turtle nesting in the northeastern Red Sea) and nearby reefs.

“In some cases, they moved from Saudi Arabian waters all the way to Egyptian waters near the entrance of the Suez Channel, which is an area with intense human activity, including shipping and coastal development,” Barrios-Garrido says. “Seeing how far these turtles travel—and how closely their final destinations overlap with busy human-used zones—really highlighted how exposed they can be once they leave their nesting beaches.”

As the conservation focus expands to include the entire range of natural areas and resources used by sea turtles, protection of their nesting beaches remains paramount. If the emerging NEOM vision for ecologically sustainable communities proves successful, it could be applied to other areas. A 2022 paper published in PeerJ Life & Environment identified sea turtle nesting on all the sites visited in the central Red Sea, including two coastal beaches and three near-shore islands.

“A wide-scale survey of all the islands off the Red Sea coast to look for nesting evidence and migration corridors will help us identify priority areas,” said study author and then-doctoral student at KAUST, Kirsty Scott, in a press release.

As species that require both terrestrial and aquatic resources along coastlines, sea turtles are considered “umbrella” species whose habitats support a range of other species, from aquatic plants to terrestrial mammals that consume sea turtle eggs. Therefore, conservation actions that aim to sustain sea turtles in the Red Sea will also benefit other sea turtle populations and a wide range of additional species.

“Our role at KAUST Beacon Development is to generate and share this kind of science with our partners and clients, helping them understand…how development can be planned in ways that reduce risks to these endangered species,” says Barrios-Garrido.