UNH EOS Spheres_Summer

A Look Back Towards the Future

A first-of-a-kind, three-year historical fisheries study by UNH researchers finds annual catch levels in the Gulf of Maine’s Stellwagen Bank have declined fifty percent since 1900


	One of many advertisements of the federal government to market net-trawled bycatch. Photo courtesy of United States Fisheries Heritage Digital Collection

BACK IN THE 1900s, fishermen in the Gulf of Maine began catching haddock and cod using steam-powered bottom trawling for the first time. The new technique was so effective that a bycatch of shark, hake, monkfish, dogfish, skates, and rays was fully half the haul.

Rather than let the bounty go to waste, the fishing industry enlisted the help of the U.S. government to get the bycatch to market. The government crafted a series of broadsheets designed to whet the appetite of American housewives: “Low Priced And Excellent Salted And Smoked, Contains No Bones, Try It, Shark,” proclaimed one advertisement. A World War I era broadsheet pictured a skate and trumpeted, “Favorite Food Fishes Of Our Allies, Becoming Appreciated By Ourselves. Recommended As Excellent And Nutritious By The U.S. Bureau of Fisheries.”

Rich historical details like these are part of the “Stellwagen Bank Marine Historical Ecology Final Report,” a comprehensive study just published by researchers from the Ocean Process Analysis Laboratory (OPAL) at the UNH Institute for the Study of Earth, Oceans, and Space.


	Historic place names of fishing grounds and undersea features superimposed on bathymetric map of Stellwagen Bank National Marine Sanctuary. Photo courtesy of NOAA.

Prepared for the National Oceanic and Atmospheric Administration’s National Marine Sanctuary Program and the Gerry E. Studds Stellwagen Bank National Marine Sanctuary, the three-year, $600,000 study was conducted by the UNH-based Gulf of Maine Cod Project. Principal investigators of the study are Stefan Claesson, an OPAL postdoc and marine archaeologist, and former OPAL director and noted fisheries expert Andrew Rosenberg, now a senior scientist at Conservation International in Washington, D.C. OPAL co-authors include Karen Alexander, Andrew Cooper, Jamie Cournane, Emily Klein, William Leavenworth, and Katherine Magness.

“Fisheries science has typically employed a single-species approach, and few studies have examined marine ecosystems both holistically and historically,” Claesson says adding, “for the first time, this study took a multi-species, historical approach.”

Assessments presented in the report of late 19^th- and early 20^th-century fisheries on the 842-square-mile Stellwagen Bank provide baselines for comparison with current ecosystem conditions. “Through comparative analysis, long-term trends have been identified that may be useful to direct future management decisions. Our historical research revealed significant declines in animal diversity and abundance, as well as major shifts in the species composition of Stellwagen’s fisheries,” the report states. Its findings challenge currently established baselines “and should influence the direction of management actions needed to improve overall ecosystem integrity.”

The report illustrates how history and ecology reinforce the long-term significance of the sanctuary’s ecosystems and marine resources to the broader Gulf of Maine system. At the same time, it highlights the historical role of Stellwagen Bank’s marine resources in the development and well-being of Gulf of Maine coastal communities.

The authors recommend that further studies be done to “extend historical trends and baselines for fish populations, species richness, and habitat conditions” back to around 1800. “In the early 1900s Stellwagen had already been fished for 300 years so it was already a very degraded ecosystem,” Claesson notes. “This led us to recommend further historical analysis be done to understand what Stellwagen looked like before all the fishing began, and also to consider climate change issues, which we didn’t look at in this study.”

The Stellwagen report grew out of work being done at OPAL on the decade-long Census of Marine Life and its History of Marine Animal Populations or HMAP project. HMAP is a global, interdisciplinary research initiative studying past ocean life and human interaction with the sea. Some 100 researchers from around the world are involved in the effort.

One interesting finding was the progressive influence technology and technology change exerted on the Stellwagen ecosystem. As particular fisheries resources decline over time, Claesson explains, “people come up with new technologies to increase harvest, but that only works for a short time. Then harvest declines again or the system crashes. The technology is improved on old grounds or the fishing is moved elsewhere and the cycle begins once more. With each iteration ecosystems decline further and eventually change can be measured in orders of magnitude." Claesson adds, "If you only looked at one short period of technological change, an increase in catch might lead you to believe that things were going pretty well. But when you look farther back in time, the cycles of peaks and drops show conditions just getting worse and worse.”

The report was based on abundant historical documentation by the U.S. Fish Commission, including a detailed series of fishermen interviews from the late 19^th century. A precursor of NOAA, the U.S. Fish Commission formed, Claesson says, because fishermen complained to the government about declining fisheries. “They wanted to find out why this was happening and wanted the government to conduct studies.” Many fishermen today are skeptical of NOAA science and management agendas with respect to the fisheries. However, in the late 1800s fishermen “brought information about fisheries to the attention of government scientists, and their observations and perspectives were reliably accurate. And I think the same can be said of fishermen today,” he says.

The report will be posted on the web as part of the NOAA National Marine Sanctuaries Conservation Series, which provides a forum for publication and discussion of the complex issues the National Marine Sanctuary Program faces.

by David Sims, Science Writer, Institute for the Study of Earth, Oceans, and Space. Published in Summer 2010 issue of EOS Spheres.