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Can the Chesapeake Bay (and its Signature Blue Crabs) Recover?

Crabbing on the Chesapeake Bay

Crabbing on the Chesapeake Bay Steve Helber / AP file

Blue crab season in the Chesapeake Bay is just around the corner. To fill his coffers between now and then, third-generation Virginia waterman J.C. Hudgins is fishing for menhaden, a type of fish used for bait. What he's seen in recent days comes as good news: clear water to a depth of eight feet.

"Ten years past, you couldn't do that," he said. "And so you know the water quality has improved considerably."

The Chesapeake Bay is a 200-mile long estuary that runs from Havre de Grace, Maryland, to Norfolk, Virginia and is fed with waters streaming in from a 64,000-square-mile watershed that includes portions of six states and the District of Columbia.

Until recently, the bay was choked with nutrients and sediment spilling in from the 17 million people that call the watershed home. Annual blooms of sunlight-blocking algae coated hundreds of football fields' worth of the bay and then, in the process of decay, snuffed the waters of oxygen and life. Oyster bars were raked flat, rockfish sickly and scarce, and overharvesting drove blue crabs into a death spiral.

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After decades of failed cleanup efforts, the tide turned in 2010 when Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the District of Columbia reached an enforceable agreement with the U.S. Environmental Protection Agency to restore the bay's health by reducing pollution in its watershed. By 2017, 60 percent of pollution control measures need to be in place, with all of them achieved by 2025. Along the way, the states and District of Columbia must meet specific milestones every two years.

The agreement is the subject of an ongoing legal challenge alleging overreach of Environmental Protection Agency authority, but most stakeholders agree the bay, for the moment, is headed in the right direction. The years ahead, however, present more disruptive cleanup actions to implement.

"Not only do they cost money, but they affect people and their choices and their livelihoods, particularly, for example, in agriculture," said Donald Boesch, a marine scientist and president of the University of Maryland Center for Environmental Science.

Too much of a good thing

The bay's troubles stem from "too much of a good thing -- that is the nutrients nitrogen and phosphorus," said Rich Batiuk, the associate director for science, analysis, and implementation with the U.S. Environmental Protection Agency and the Chesapeake Bay Program, a regional partnership among states, federal agencies and other stakeholders that leads and directs bay restoration efforts.

"They are called nutrients because they are the building blocks," he said, "but like anything, whether a human or an ecosystem, if we get too much of it, it causes health issues."

The nutrients are food for algae, which in turn feed oysters and fish in the bottom links of the food chain. But the nutrients spur an algae supply that far outstrips demand. The excess sits on the surface and blocks sunlight from nourishing bay grasses that provide a habitat for crabs and young fish as well as food for migratory birds. As the algae die, bacteria munch on them, depleting bay waters of oxygen in the process, and creating what are known as dead zones.

Along with nutrients, rivers and streams wash sediments into the bay, which cloud the waters and slime up oyster bars so much that they are unsuited to host the next generation of the essential filter feeders, Batiuk said.

The road to recovery

The bay's health hit rock bottom in the early 1980s, according to Will Baker, the president of the Chesapeake Bay Foundation, an environmental group that advocates for bay restoration. Since then, cleanup efforts have progressed in fits and starts culminating in 2010's agreement under which the six bay states and the District of Columbia released plans to achieve limits on nutrients and sediment.

"It is working, not only in terms of the system, in terms of ecology and biology, but so far it is working politically," Baker said.

The sources of the nutrients range from coal-fired power plants, wastewater treatment plants and urban and suburban lawns to farms, pastures, and hen houses. The biggest success stories are found in the reduction of nutrient pollution from wastewater treatment plants, which have been upgraded throughout the bay states, and retrofitted power plants that scrub nitrogen from smokestacks.

A sign of the pollution reduction is the resurgence of oysters and bay grasses, both focuses of aggressive restoration efforts, Baker said.

Going forward, he and other observers said, the biggest challenges lie in reducing pollution from agriculture. A key political step was taken this March in Maryland, where lawmakers hatched a plan to restrict the amount of chicken manure that farmers spread on their fields as fertilizer. The manure is an inexpensive source of nitrogen and phosphorus, which helps crops grow.

The Chesapeake Bay and the Conowingo Dam 2:16

The decades-old process closes a cycle, Batiuk said, "but they have been applying it in a way to satisfy the nitrogen requirements and thereby adding far more phosphorus than the crops need," and some of that ends up washing into the Chesapeake Bay where it fuels algal blooms.

"This didn't happen overnight, none of this. This is called legacy phosphorus, legacy nitrogen, and, you know, legacy is a long term," said Chuck Fry, a dairy farmer and president of the Maryland Farm Bureau. His group supports the state's phosphorous management tool, as it is called, but cautioned that reducing the nutrient is going to take time. "We don't want to run a business out of business," he said.

But shifts in the agricultural enterprise are likely necessary to make the required nutrient reductions, according to Boesch. He said, for example, that if farmers grew more fruits and vegetables for human consumption rather than corn to feed livestock and fuel cars, "we can reduce the pollution losses and really accomplish the bay restoration goals."

Crab survey

In addition to efforts to clamp down on nutrient and sediment pollution pouring into the Chesapeake Bay, fisheries managers have stepped up efforts in recent years to restore depleted oyster bars as well as set limits on the harvests of crab, rockfish, and other species. As a result, oysters, which can filter upward of 50 gallons of water daily, are on the rebound, and rockfish numbers are on the rise.

The conundrum is blue crab, according to Tom Miller, an expert on the iconic crustacean and director of the University of Maryland's Chesapeake Biological Laboratory. A lethal combo of overharvest, pollution, and weather resulted in more than a decade of consistently low numbers of crabs beginning in the early 1990s. In 2008, fisheries managers stepped in with actions aimed at conserving fertile females.

"For the next two or three years, crab numbers went through the roof and we really thought we had licked this problem and it was probably time for me to retire," Miller said. Then, the population crashed from 765 million in 2012 to 297 million in 2014.

What happened? Unusually cold winter weather is one explanation. An over-abundance of red drum, a crab-eating fish, is another. Yet another is an overharvest of male crabs.

The official reading of crab abundance, known as the winter dredge survey, will be revealed in May. What it will say is unknown, but "more so than the last couple of years, it will be a real bellwether for the future of crabs and the future of crab fishing," Miller said.

Waterman Hudgins said he's heard whispers of an uptick in crabs, which fits with the cyclical nature of abundance.

"If you look back over the past 30 years, you'll have two, three, four good years of abundance and then two or three years when it will drop," he said. "Mother Nature and God and everything working -- the winds and the climate and the ecology, all of that -- has a big effect on the crabs."

Just as important, noted Batiuk, is continued progress toward cleaning up the bay. "Good fisheries management," he noted, "needs to be balanced by good habitat and good water quality."