Restoring the number of sea turtles has also restored their ecosystem

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Under cover of darkness, the female turtle crawls on the beach. Its front flippers alternate to pull 250 pounds of shell and meat down the dunes, inch by inch. Encased in heavy armor of fused ribs and bony plates, an adult sea turtle is safe from all the fiercest predatory fish. The smooth shell, oar-like fins, and massive lungs allow sea turtles to glide gracefully through the saline underworld. On earth, gravity and friction reign. She’s only down for an hour or two. Each turtle makes this trip up to six times in a single nesting season. No wonder she needs two to three years to recover before she can nest again. Her brief visit will help preserve one of the world’s most nutrient-poor ecosystems, even if a single egg never hatches.

Like much of the world’s megafauna, sea turtle populations have declined dramatically during the 20th century. Commercial trawlers caught turtles as bycatch, and beach communities allowed condos at nesting sites. But the story of the sea turtle took a different path than the endangered rhinoceros and a near-extinct porpoise called the vaquita.

Thanks to monumental conservation efforts, sea turtles along the Atlantic coast of the United States have reversed their downward spiral. Through properly enforced policy and management, we have protected beaches, enacted lighting ordinances, and changed the way we fish. Since the 1990s, trawlers in US waters have been legally required to use nets that protect turtles. A multi-agency land acquisition effort in 1991 resulted in the creation of the Archie Carr National Wildlife Refuge, whose beaches hold 20–35% of loggerhead and green sea turtle nests in the United States. Coastal towns regulated the use of artificial lighting which confused sea turtles. Organizations and volunteers provided tireless support outside of statutory programs.

The results were astounding. There were 3,950 loggerhead sea turtle nests in Georgia in 2019. These are record numbers and about triple the average number of nests over the past three decades. The return of the loggerheads is impressive, but the revival of the green sea turtle is even more amazing. There were fewer than 300 nests in 1989 on 27 of Florida’s main beaches where the animals come to nest. In 2019, that number reached 41,000.

While sea turtle numbers have increased again, a byproduct of this rebound is the restoration of dune ecosystems.

The salty winds, unpredictable storms and porous sands of coastal dune ecosystems make them quite desolate places. When sea turtles lay their ping-pong ball-sized eggs, they involuntarily transfer energy and nutrients to plant life, regardless of how many eggs actually hatch. Each embryo is immersed in nutrient fluids and encased in a tough calcareous shell. The developing young will absorb much of the nutrients, but the dune plants welcome the bits of calcium that are left over. Eggs that fail to develop or hatch will provide even more supplement. With a protein shake of shell fragments and rotting hatchlings, dune grasses extend their root systems into ever-changing sands. The result is a more stable dune system. Healthy dunes are nature’s first defense against rising seas and the stronger storms expected from climate change.

Sea turtles along the United States’ Atlantic coast have rebounded from near extinction thanks to new conservation strategies that have faced unexpected threats. Simple adjustments to human behavior, such as installing outdoor light fixtures with shields to direct light downward, have brought tangible benefits to sea turtles. Similar strategies could be applied to protect birds as they migrate above our overlit cities, streets and porches. Likewise, after decades of death in trawl gear, conservationists and fishermen have come together to design nets that allow turtles to escape without jeopardizing precious shrimp catches.

The survival of sea turtle populations depends on our continued vigilance. Rising seas and temperatures present new threats to these prehistoric reptiles. We will have to work to protect their future nesting grounds, which may be further inland and on beaches further north. As we prepare for the impacts of climate change, it is imperative that we give wildlife space to migrate to suitable habitats. One such strategy is to protect land in connected corridors that represent a variety of physical habitats and temperature gradients. In other words, our best bet is on diversity – not just of species, but of places.

Life in the midst of the sixth mass extinction is exhausting. Linked to political and social upheavals, and it is hard to find a reason to get out of bed. Like a clutch of turtle eggs on a desolate beach, we burrow into them. But the oxygen filters through the grains of sand, and there is still life. Despite high tides and tropical storms, hatchlings manage to emerge. U.S. too. Their persistence, both as a species and as individuals, gives us hope to live in a changing world. The complex relationships between egg fragments and dune grasses inspire and ground us. Perhaps we can be inspired to action and grounded in humility.

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