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In 2017, Maine’s seafood harvesters landed more than $569 million in seafood,¹ sustaining the unique generations-old culture that distinguishes the Maine coast. Lobsters—worth more than $430 million—accounted for nearly 80 percent by value of that haul.² Since 2004, the waters of the Gulf of Maine have warmed faster than nearly any other body of water on Earth,³ creating ideal temperatures for lobsters and leading to a population boom.⁴ Yet, amid the good fortune of this near-record haul—the fourth-highest in Maine history—the state’s lobstermen are far from jubilant as they watch ocean temperatures continue to climb and the lobsters continue their northward shift.⁵

The worry for many is that the waters of the Gulf of Maine may become too warm to support lobsters. Dave Cousens, a former president of the Maine Lobstermen’s Association, told The New York Times, “Climate change really helped us for the last 20 years. Climate change is going to kill us, in probably the next 30.”⁶

Many marine species are temperature-sensitive. As the oceans warm, fish populations have been observed shifting poleward⁷ or to deeper water, in search of the cooler temperatures to which they are adapted.⁸ More than two-thirds of marine species in the waters off the Northeast United States coastline are fleeing their traditional habitats in search of their preferred water temperatures.⁹ These shifts in fish and shellfish distribution in turn can cause ecological disruptions as predators become separated from their prey and the timing of seasonal migrations change.¹⁰ These shifts also cause economic disruptions as fish and shellfish stocks decline or migrate away from traditional fishing grounds. Fish and shellfish once caught in large numbers in certain locations are now scarce in those same places. The timing of fishing seasons and of migrations has shifted as well,¹¹ and increasingly more warm-water fish species are showing up on lines and in nets at higher latitudes.¹²

Globally, scientists estimate that the fishing industry will lose approximately $10 billion in annual revenue by 2050 due to the expected ocean temperature increases under “business-as-usual” emissions trends.¹³ In North America, scientists estimate that high greenhouse-gas emissions scenarios will cause 448 of 686 key North American marine species to migrate as far as 1,000 km, or roughly 540 nautical miles, from their traditional habitats in the next 100 years.¹⁴

The stakes for America’s fishing communities—and for the U.S. economy broadly—are high. Commercial and recreational fisheries together supported 1.6 million jobs in 2015 and generated $207.6 billion in sales, $62.4 billion in income, and $96.6 billion in value-added impacts.¹⁵

Many fishermen understand the negative consequences of climate change on their livelihoods. In 2014, the Center for American Progress led a survey asking commercial fishermen in New England about their perspectives on the changes occurring on the water. CAP found that “65 percent of fishermen surveyed believe climate change could leave them ‘unable to profit’ and ultimately ‘forced out’ of their fishery,”¹⁶ leaving them with no option but to switch to a new target species or a different profession entirely. According to the survey, “More than 80 percent of those who have noticed a warming trend attribute it to climate change.” The concerns of fishermen, combined with the clear scientific evidence, have prompted many regional fishery managers to begin contemplating how to incorporate climate change into fisheries management in a way that upholds the stringent standards of the Magnuson-Stevens Fishery Conservation and Management Act (MSA).¹⁷

Scientific and economic evidence characterizing the impacts of climate change abound and provide a clear call to action. But perhaps more compelling are the stories of the men and women of today’s U.S. recreational and commercial fishing industries who are being harmed by changes carbon pollution has caused in the oceans. Hearing from American fishermen not only improves understanding of the changes occurring in marine fisheries but also highlights the extent to which coastal communities’ economies and social cohesion are dependent on American fisheries.¹⁸

For the third year in a row, 2016 set a record as the hottest year ever measured by scientists,¹⁹ part of a clear, worldwide warming trend.²⁰ Yet, even as atmospheric warming causes dramatic impacts such as the rapid retreat of Arctic sea ice²¹ and supercharged hurricanes,²² scientists have found that 93 percent of the excess heat trapped by human-made carbon pollution has been absorbed by the ocean.²³ Global warming means ocean warming.

The same carbon pollution responsible for warming is also driving chemical change in the oceans, in a process commonly known as ocean acidification.²⁴ Ocean waters have absorbed nearly half of all anthropogenic carbon dioxide emissions—those caused by humans and human behavior—in the 19th and 20th centuries,²⁵ and when seawater absorbs carbon dioxide, it becomes increasingly corrosive. The shells and skeletons of many ocean organisms are made of calcium carbonate, which literally dissolves under high-enough concentrations of acidified seawater.²⁶ Carbon pollution’s effect on ocean chemistry also threatens fisheries that depend on calcified species such as urchin, oysters,²⁷ and scallops,²⁸ or on fish that prey heavily on such calcifiers, such as some salmon. Additionally, some fisheries depend on calcifiers such as coral for fish habitat and are thus adversely affected by ocean acidification.²⁹

In a comprehensive survey published in the summer of 2018, scientists writing for the United Nations’ Food and Agriculture Organization (FAO) succinctly summarized the effects of climate change on fisheries:

Driven by greenhouse gas emission from human activities, the ocean is getting warmer, more acidic, and its oxygen content is declining; these changes cause large-scale changes in marine biodiversity. The changes in ocean conditions are expected to continue to alter patterns of global marine primary productivity and biodiversity, with consequences for the potential fisheries catches, impacting food security in the twenty-first century.

The projected decrease in maximum catch potential may be driven by the direct effect of warming on fish physiology, by a decrease in their food (phytoplankton and zooplankton), and/or loss of habitat.³⁰

The bottom line, they concluded, is that “increasing carbon emissions are likely to reduce global fisheries catch potential” by as much as 25.2 percent by 2100, under business-as-usual emissions trends.³¹

Climate change-driven extreme weather events and sea level rise also put the physical infrastructure of coastal communities at greater risk.³² Seafood production and distribution relies on coastal ports, reliable power sources, and infrastructure, all of which are easily compromised by severe storms and coastal flooding. For example, in 2017, Billy Kelly, executive director of the Florida Keys Commercial Fishermen’s Association, estimated that Hurricane Irma destroyed or scattered more than 40 percent of the spiny lobster traps in Monroe County waters just one month into the season,³³ devastating a $50 million industry relying on what is regularly the most valuable commercial species in the Florida Keys.³⁴

From the lobstermen of Florida to crabbers in Alaska, fishing communities depend on their local marine ecosystems. However, because climate change is not uniform or linear, the continued release of anthropogenic carbon will affect each local region differently. This report shares some of the localized effects of global climate change that American fisheries experience today.

Florida

With 1,350 miles of saltwater coastline, commercial and recreational marine fishing is a big business in Florida.³⁵ In 2015, Florida’s commercial and recreational marine fishing industry supported 176,000 jobs and generated $28.7 billion dollars in sales, ranking as the third-highest state in employment impacts and second-highest state in sales, income, and value-added impacts. Florida leads the nation in recreational angler trips, recreational fishing jobs, and local taxes generated by sportfishing.³⁶ In saltwater-fishing license fees alone, Florida generates $26.8 million dollars, 46 percent of which come from out-of-state fishermen.³⁷ Yet, warming waters and more frequent extreme weather events are already damaging the Florida fish stocks that support this key economic sector.

Nationally, fish stocks are managed on a regional basis, with quotas set by regional fishery management councils and state agencies based on historical catches and regular scientific assessments of the number of adult and juvenile fish present. As ocean temperatures skyrocket, heat-sensitive fish and other marine life are moving to more comfortable waters. By moving away from the habitats and fishing grounds on which those historical records are based,³⁸ climate change is causing a mismatch between where fish actually are and where they are allowed to be caught, leading to severe economic hardship for fishermen and the businesses and communities they support.

“Cobia are very much a migratory fish, and their migratory patterns from Texas and Florida are both about six weeks off,” said Brandon Shuler, a professor at the University of South Florida and an avid recreational fisherman. “There are some regions in the United States where the fishing season is historically open during a certain period of time, and now, the fish aren’t coming until after the season is over,” Shuler said.³⁹ Reports of declining cobia catches along the Florida Panhandle prompted the Florida Fish and Wildlife Conversation Commission (FFWCC) to reduce the number of cobia that fishermen can catch in the northern Gulf of Mexico.⁴⁰ Meanwhile, further south, cobia catches have been plentiful. WUFT News reported FFWCC Commission Chairman Brian Yablonski wondering, “Is it possible that all the Panhandle fish [those that typically migrate up into the Panhandle] have gone to Central Florida and are just hanging out there? It sounds like we have an abundance in one area and a dearth of fish in the other.”⁴¹

The science underlying why cobia are showing up in different areas of the Gulf of Mexico could be related to the warming water temperatures in the Gulf: In the winter of 2016, ocean temperatures in the Gulf of Mexico did not dip lower than 73 degrees Fahrenheit. Cobia are known to prefer warm water temperatures above 68 degrees Fahrenheit and to migrate north in the summer months, possibly to stay in their preferred water temperatures.⁴² The warm water temperatures in the Gulf could be contributing to cobia population migration changes.

But cobia is not the only commercially important species that has fled its typical habitat for more comfortable waters. Terry Gibson, a former charter fisherman and lifelong recreational angler, explained the importance of the king mackerel to anglers who travel across the nation to fish in Florida water. Gibson and others have noticed a shift over the past five years in the area that South Atlantic king mackerel and Gulf of Mexico king mackerel populations meet to mix. “I can show you my logs and my depth finder that [the water is] 2 or 3 degrees warmer almost all the time,” said Gibson, who believes climate change is playing a large role in the shifts of king mackerel populations.⁴³

Gibson’s story matches the available science. Gulf of Mexico king mackerel are known to follow a similar pattern to that of cobia, spending summers in the northern part of the Gulf of Mexico and migrating south in the fall. At the same time, a separate Atlantic population of king mackerel also migrates south in the fall, and the two distinct groups eventually mix along the southeast coast of Florida. ⁴⁴ Recently, however, scientists have shown that the mixing zone of the two populations of king mackerel had shifted to the south side of the Florida Keys, because the water is colder there.⁴⁵

Fishermen have also noticed distinct changes to the sailfish migration, which have affected sailfish tournaments, jobs, and tourism revenue on the southeast coast of Florida. Thanks to catch-and-release fishing and a ban that prohibited destructive longlining in the straits of Florida, sailfish in the Jupiter area are one of the few populations that is not overfished.⁴⁶ “Since 2003, you could almost guarantee a catch for a customer, and odds are you would probably would catch four or five [sailfish]. The colder it is, the better it is for this fishery, so you would go during nor’easter fronts,” Gibson said. “Today, the cold fronts are fewer and farther between, and we advertise like crazy when it does happen—really impacts local economy and the local sailfish tournaments.”⁴⁷

Captain Randolph “Bouncer” Smith, a charter boat captain based out of Miami Beach, Florida, recounted similar stories of his 50 years in the charter industry:

In the 1970s [and as recently as 2005] in November and December you would have great sailfishing, and in January and February, everyone would jump out of their skin when there was a cold front. You would see 20 sailfish fighting over your bait. Now you don’t see those waves of sailfish, because it’s 80 degrees in winter. And it has a big impact. You used to see 30 charter boats, and every boat would be fishing two half-day trips through Easter. Now, with the lack of fish and warmer water, there might be five boats out of 40 in Miami who are able to fish.⁴⁸

The sailfish, he noted, are now being seen off the coast of South Carolina and in areas where there are no established fishing tournaments or charter fishery clientele. Smith described how there are now many days in the winter where his customers have nothing to catch—hurting both his marketing ability and bottom line.

The same is true for Florida’s iconic tarpon fishery. Like sailfish, warmer water means that the tarpons’ migration patterns have shifted. Smith said that for him, the impacts have been substantial. “I’m forfeiting as many as 20 tarpon trips a month in the winter due to warmer weather. I had a guy who only worked nights for me, and now, he can’t make a living on tarpon, because I can’t guarantee [customers] we will catch fish. That guy literally went from a dependable income to scrounging,” Smith said.⁴⁹ He believes the fish are comfortable staying north, because the water has gotten warmer.

The Mid-Atlantic

Along the Mid-Atlantic coast, commercial and recreational fishing represents an important economic driver. In 2015, the New Jersey fishing industry supported 47,633 jobs and generated $7.8 billion in sales; New York supported 47,720 jobs and generated $6.2 billion in sales; and Virginia supported 21,844 jobs and generated $1.6 billion dollars in sales.⁵⁰ Yet, the fishing industries in all three states are under threat as researchers have found marine species to be shifting an average of 0.7 of a degree of latitude, or roughly 50 miles, north and 15 meters deeper in the water.⁵¹

Fishermen along the Mid-Atlantic states are noticing similar shifts in the distribution of marine fisheries as ocean temperatures in the Atlantic continue to warm.

Charles Witek, an attorney and avid saltwater angler, described his experience: “Summer flounder off the coast of New York are having poor spawning seasons; everyone is switching to black sea bass, which have become more abundant due to warming waters. I never caught a black sea bass in Long Island Sound, in all 27 summers that I lived in Connecticut. Now, they are an important part of the regional fishery.”⁵²

Dolphinfish, commonly known as mahi-mahi, are a tropical fish traditionally caught between Florida and North Carolina. Now, they are increasingly found in the waters off New York, New Jersey, and Rhode Island.⁵³ Witek said, “When I started fishing offshore in the early ‘80s, once in a while, someone got a dolphin[fish], but only when the warm canyon water came inshore. But they were targets of opportunity. … Now, I go out looking for dolphin[fish], and so do a lot of people. My wife and I go out and we catch all that we want. A friend of mine is a charter boat captain and is always talking about how he has dolphin[fish] on top chasing bait.” Scientific research on the species supports Witek’s observations, indicating that the wide-ranging species exhibits significant sensitivity to sea surface temperature and is caught recreationally only in waters warmer than 66.2 degrees Fahrenheit, while catch rates peak at 80.6 degrees Fahrenheit.⁵⁴

Fishermen are also reporting noticing more of what they term “funny fish,”⁵⁵ or unusual species showing up in their waters. “You can cast a net under lights in Virginia and catch Gulf shrimp—not grass shrimp, Gulf shrimp. The guys that are running oyster aquaculture, it’s becoming common to see Nassau grouper juveniles in the cage—you see it, and you think you’re the only one. Two weeks later, someone else has got one too,” explained Tony Friedrich, former executive director for Maryland’s Coastal Conservation Association and an avid recreational fisherman in Maryland. He added, “I know it’s hard to believe, but adult tarpon are becoming frequent summer visitors to the southern Delmarva Peninsula.”⁵⁶ Witek also mentioned that “funny fish” are