Steve Gephard knows what it feels like to swim upstream. For 46 years, he pursued a noble goal against long odds: restoring a viable population of Atlantic salmon in the Connecticut River.

Every year, he and his colleagues at the Connecticut Department of Energy and Environmental Protection would stock the river and its tributaries with hundreds of thousands of newly-hatched salmon, hoping that enough would return as adults to spawn and build a sustainable population. They built fish ladders—a series of pools built like steps—on the rivers, too, so the salmon could circumvent dams as they moved upstream.

It didn’t work. Last year, cameras at the Connecticut River fish ladders spotted just four returning Atlantic salmon, down from hundreds in the 1980s and perhaps tens of thousands before European settlers began choking the river and its tributaries with dams and pollution in the late 1700s.

While Gephard’s efforts managed to at least partially overcome centuries of overfishing and dam building on the Connecticut, they were ultimately foiled by the drastic ecological transformation climate change has wrought in the warming North Atlantic Ocean, where these salmon spend most of their lives. Ocean currents are changing as the Arctic ice melts and rising water temperatures to the south alter food sources and draw new predators.

In 2012, the federal government officially abandoned efforts to restore the natural salmon population on the Connecticut, though Gephard continued to supervise a much smaller legacy restocking program until his 2020 retirement.

“The opportunity for a true restoration in Connecticut has passed,” said Gephard, now 70. “There is no real delusion that this legacy program is going to grow a salmon population. Its intent is to keep the species alive in the watershed for educational, research and cultural reasons.”

With every passing year, the small Connecticut River population becomes more like a genetic zoo, he acknowledges. But it’s a zoo that can still serve an important purpose, he said, by teaching people—especially schoolchildren—what has been lost, and what still could be saved in river systems in Maine and other places where wild salmon populations are not quite so decimated.

Today Gephard approaches this educational mission with the same zeal he formerly applied to his restoration efforts. A species as fascinating and ecologically important as Atlantic salmon, he said, is worth the effort: “As they say, you don’t catch the salmon, the salmon catches you.”

Wild Atlantic salmon disappeared from the Connecticut River just after the turn of the 19th century, when dams were built that prevented the fish from reaching their historical upstream spawning grounds. During this U.S. Industrial Revolution, nearly every tributary in the river was dammed to produce inexpensive power.

In 1867, the Fish Commissioners of the States of Connecticut, Massachusetts, New Hampshire and Vermont began to investigate the disappearance of both the Atlantic salmon and American shad. The states stocked hundreds of thousands of juvenile salmon into the Connecticut River. The commissioners observed that 800 adult salmon were able to return to the river, but without a way to control commercial fishing or build efficient fish ladders around dams the restoration attempt ultimately failed before the end of the 19th century. The efforts would not begin again until 1965.

That year, the U.S. Congress passed the Anadromous Fish Conservation Act, which provided federal funding to restart the restoration efforts. The four states would come together again in 1967, 100 years after their initial attempt, to recommence the stocking of juvenile salmon. This time, however, they had the technology to create fish ladders to transport the migrating salmon past dams.

It took less than a decade for the program to find its first hint of success. In 1978, at 26, Gephard caught the first adult Atlantic salmon to return to the river and wriggle its way up a fish ladder as part of the federal restoration program—and he was hooked for life.

Gephard’s love of migratory fish began during the summers his family spent along the Connecticut in their cottage away from the hustle and bustle of Chicago. He was so enamored that he pursued a master’s degree from the University of Connecticut studying migratory fish in the Salmon River, another tributary of the Connecticut. After a year in the U.S. Peace Corps, where he served as a fisheries biologist in Lesotho in southern Africa, he returned to Connecticut in 1978 and secured his first job with the state, operating a fish ladder on the Farmington River.

At first, things seemed to be going well. During the 1980s, the number of returning salmon steadily increased; hundreds began returning to the river each year. But by the 1990s, the number of all ocean fish returning to rivers along the East Coast started dropping off. Many experts say that the already fragile Atlantic salmon population was affected greatly by changes in the North Atlantic caused by climate change.

“Atlantic salmon are one of the poster species for climate change,” said Bruce Williams, who worked with Gephard at the state agency and succeeded him as the head of the salmon restocking effort. According to Williams, the increased effort during the 1990s to restore the Atlantic salmon to the Connecticut River likely masked the true decline of the species. As the state stocked more and more fish into the river, fewer and fewer began to return.

Atlantic salmon spawn in freshwater rivers throughout North America and Northern Europe. Once they grow large enough, they migrate downstream into the ocean. Increasingly, though, the fish are having trouble surviving their marine journey.

The ocean currents they must swim against to reach their feeding grounds between Newfoundland and Greenland are becoming stronger and colder due to increased ice melting. This forces the fish to use up more energy to reach their oceanic home. Rising water temperatures are also causing the species’ food sources, such as capelin, to become smaller and move farther north, while also drawing silver hake and other predators into the salmon migration zone.

“We know what happened—the ocean has changed,” said John Kocik, chief of the Atlantic Salmon Ecosystems Research Team at the U.S. National Oceanic and Atmospheric Administration. “The question is when, or if, it is going to shift back.”

The shift Kocik references occurred to the North Atlantic Oscillation, a pattern of regional variations in air pressure that have an impact on the climate across the Eastern U.S. to Siberia and from the Arctic to the subtropical Atlantic. In the 1990s, this oscillation shifted into the most extreme positive state in 175 years of record keeping. This shift caused warmer than average winters across the Eastern U.S. to Northern Europe and also accelerated the melting of Arctic sea ice.

The number of Atlantic salmon returning to spawn in rivers in both North America and Northern Europe have been drastically reduced due to the combined pressures that made their oceanic journey more difficult to survive. On the Connecticut River, the change meant that any hopes for the successful restoration of a self-sustaining population slipped away.

“The last so-called good year for Atlantic salmon return was 1992,” said Williams. “Then there was a slow, steady decline until the 2000s, and things just dropped to the floor.”

When the federal government finally shut down the federal restoration program in 2012, Connecticut residents didn’t want to give up. They inundated the state agency with phone calls urging it to continue stocking salmon in the river, according to Williams.

So Gephard decided that the state would maintain a smaller, legacy version of the program, which he supervised until his recent retirement. Of the 200,000 young salmon the state places in the river every year, Williams now expects less than 10 adults to return.

Even river systems that never completely lost their wild salmon still depend on hatcheries now. In Maine, for example, 676 adult fish returned to state rivers in 2021, said Rory Saunders, a salmon recovery coordinator at the National Oceanic and Atmospheric Administration. “Up here in Maine they’re still hanging on,” Sanders said, “but they’re in pretty bad shape.” In 2022, 1,257 returning adult salmon have been counted in the Penobscot River so far.

While Gephard was saddened by the shuttering of the federal restoration program and the failure of his professional efforts on the Connecticut River, he said that he is not pessimistic about broader Atlantic salmon recovery. To him, the salmon were more than just a job, he fell in love with the species.

Now he’s determined to help people absorb the lessons of the salmon story—with a special focus on schoolchildren. He is a frequent speaker in the volunteer-led Salmon-in-Schools program, which was launched in 1995 by the Connecticut River Salmon Association and educates children in dozens of public schools about the loss of the species in the state. The kids even raise eggs from the Kensington State Fish Hatchery in chilled aquarium tanks in their classrooms.

When the eggs hatch and the small fish absorb their yolk sacs, typically at the end of April or early May, the students take a field trip to release the fish into tributaries of the Connecticut River. “At least the kids know what they lost,” explained Kocik.

Gephard recognizes that the true importance of the Salmon-in-Schools programs is imparting a sense of the importance of global conservation work at a young age. While some kids do go on to pursue careers in biology and conservation, he thinks it is just as influential that the students are encouraged to care about the management of a species and its habitats and aquatic resources.

He remains optimistic about the fate of Atlantic salmon in other parts of the world. “Nothing is a slam dunk but there is enough possibility to keep people fighting for the species,” he said.

Atlantic salmon have rebounded from previous changes in climate and respond to selection pressures fairly quickly. For example, during the Little Ice Age that lasted from approximately the 16th to the 19th century, Atlantic salmon retreated south to the Chesapeake Bay. As the climate began to warm again around 1850, the species abandoned their mating grounds in the Chesapeake and returned to more northern waters.

Today, the difference hinges upon the speed at which the planet is heating up. Scientists are unsure about the trajectory of climate change and whether the Atlantic salmon will be able to adapt quickly enough to their rapidly changing selection pressures. “Anyone who cares about the Atlantic salmon has to care about climate change,” said Gephard.

Even though his days as a state regulator are over, Gephard is still the chairman of the West Greenland Committee for the North Atlantic Salmon Conservation Organization, which works with six governments and the European Union to conserve wild Atlantic salmon populations in the North Atlantic Ocean.

Tim Sheehan, who has worked with the North Atlantic Salmon Conservation Organization for about 15 years, said he respects Gephard’s continued advocacy for migratory fish as well as his efforts to ensure that the lessons of the Connecticut restoration effort aren’t forgotten as similar efforts continue elsewhere.

Sheehan adds that the scientific knowledge of the lives of Atlantic salmon during their time off the coast of Greenland needs further exploration. The decrease in oceanic productivity that occurred after the oscillation shift in the 1990s, however, is thought to have lowered the energy density of the salmon’s sources of prey. He said the most dangerous part of their oceanic journey occurs on the way to Greenland and on the way back to the rivers to spawn.

Atlantic salmon numbers continue to decline despite a marked reduction in exploitation. In 1983, the North Atlantic Salmon Conservation Organization created a large protected area spanning 12 nautical miles that immediately reduced the amount of commercial wild salmon fishing. However, research shows that the number of salmon eggs needed to ensure a single salmon survives its first year at sea has doubled since 1990.

“We all need to look at what happened in the Connecticut River,” said Gephard. “We lost the opportunity to restore them, so we should look at what happened in southern New England and use that as a cautionary tale to really support recovery efforts in Maine.”

This story is published in partnership with Inside Climate News, a nonprofit, independent news organization that covers climate, energy and the environment. Sign up for the ICN newsletter here.