【Para.1】At the intersection of Ohio, Michigan and Indiana, the corn monoculture melts away to reveal green rolling hills and deep gorges. The lush forest is pockmarked by steep-banked ponds, carved out by retreating glaciers 10,000 years ago. Standing waist-deep in a forest pool, Megan Seymour scans the shrubby banks with binoculars.

【Para.2】A slight change in colour and texture spotted in the tangled buttonbush swamp reveals her quarry: a thick, glossy, copperbelly water snake (Nerodia erythrogaster neglecta). Seymour hoists up her waders and ties back her hair as she prepares to grab the water snake before it can disappear into the murky water, taking with it one of the last chances to save the species.

【Para.3】Though non-venomous, a bite from a 1.2-metre (4ft) water snake can be painful. But Seymour, a biologist with the US Fish and Wildlife Service, has lost count of the number of snake bites (all from non-venomous species) she has had, and is quick to add: “They aren’t slimy, they aren’t mean, and they aren’t trying to get you.”

【Para.4】The copperbelly water snake – named for its tangerine-orange underside – inhabited what was one of the largest wetland areas in North America. Roughly the size of Connecticut and stretching from Fort Wayne in Indiana across much of north-west Ohio, the Great Black Swamp was home to elk, wolves, mountain lions and black bears.

【Para.5】In the mid-19th century, farmers began to clear the trees and drain the swamp to access the fertile soil hidden beneath the water. In just five decades, the Great Black Swamp was dry.

【Para.6】Today, the copperbelly water snake lays claim to just 50 sq km (20 sq miles) of remnant swamp forest in the tri-state area – slightly smaller than Manhattan Island. Though the exact number of the reptiles is not known, experts estimate that fewer than 100 individuals, possibly as few as 40, remain. “I think they will be gone within 20 years,” says Nathan Herbert, a land steward with the Nature Conservancy, an international nonprofit organisation.

【Para.7】He believes saving the copperbelly water snake is essential to the region’s ecology because it is “an umbrella species” – the preservation and conservation of this one snake also protects habitat for dozens of other declining species that rely on the swamp forest, including the rare bobolink blackbird and the checkerspot butterfly.

【Para.8】When Seymour began searching for copperbelly water snakes in spring 2021, no one had seen one alive in the wild in almost three years. She spent more than 180 hours combing through the wetlands historically inhabited by the species but found none. “That was very concerning and pushed us down the road to captive propagation being the best option,” says Seymour.

【Para.9】Captive breeding acts as an insurance policy against extinction. Encouraging endangered species to reproduce in captivity can increase population size, maintain genetic diversity and safeguard rare species while habitat is restored for their eventual return to the wild. The California condor, red wolf and bald eagle were saved from extinction via captive breeding.

【Para.10】The US Fish and Wildlife Service is partnering with Toledo zoo, south of Detroit, to captive breed copperbelly water snakes. The zoo has successfully reared other declining native species, including the hellbender salamander and the Blanding’s turtle. No one, however, had tried to breed copperbelly water snakes in captivity before.

【Para.11】In 2022, with the help of private landowners, Seymour found and caught six copperbelly water snakes – three males and three females. “Finding six snakes was insanity,” says Seymour. “After we got the first one, I was just shaking.”

【Para.12】The snakes have adjusted quickly to captivity at Toledo zoo. “They are doing really well,” says Seymour. “They are eating, shedding and behaving as they should.”

【Para.13】In a small back room, hidden away from the zoo’s visitors, a dozen opaque plastic enclosures line the wall. Each holds a water dish, a hide and two baby copperbelly water snakes patiently waiting for a meal of chopped fish.

【Para.14】Just four months after she was caught, one of the females gave birth to 24 babies, the first copperbelly water snakes to be born in captivity. Each juvenile snake sports a subtle blotched pattern that quickly fades to black as they grow. The bellies are already tinged with their namesake copper hue.

【Para.15】Dr Matthew Cross, a conservation biologist at Toledo zoo, sees the captive breeding and reintroduction of the copperbelly water snake as a chance to right our ecological wrongs. As with medical doctors’ Hippocratic oath, conservation biologists hold an ethical commitment to prevent extinction. “Conservation biology is a crisis discipline,” says Cross. “We are always playing catch-up.” 

【Para.16】Seymour, Cross and the team at Toledo zoo have committed the next decade and a half to saving the copperbelly water snake. The zoo-reared snakes could return to the wetlands where their parents once lived as early as next year. If captive breeding is successful, “we are looking at potentially thousands of baby snakes over the next 15 years”, says Seymour.

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