Knight-Ridder/Tribune Business News, May 30, 2001 Pitem01150005

Knight-Ridder/Tribune Business News, May 30, 2001 pITEM01150005

Report: Underwater Grasses Growing Again in Chesapeake Bay.

Environmental News Network, Sun Valley, Idaho Knight Ridder/Tribune Business News

May 30--Grasses are growing once again on the floor of Chesapeake Bay, and that's good news for the more than 2,700 plants and animals, including threatened and endangered species, that live in America's largest estuary system.

The Chesapeake Bay is slowly recovering from the effects of massive development along its shores, a new report has found.

The health of underwater grasses in Chesapeake Bay indicates how healthy the bay is as a whole, and the latest survey shows an increase in Maryland waters, says Dr. Robert Magnien, tidewater ecosystem assessment director for Maryland's Department of Natural Resources.

"While we still have a long way to go in restoring the Chesapeake and Coastal Bays and their tributaries, the most recent findings show some positive trends," Dr. Magnien said.

Results released for the Chesapeake Bay this week show that Maryland bay grass acreage increased by an estimated 1,472 acres in 2000, an increase of four percent to 35,671 acres.

Bay-wide, the underwater grass acreage increased by about one percent from 1999. But in Maryland's Coastal Bays the grasses declined somewhat. There were six percent fewer acres -- just 9,696 acres in 2000.

More than 15 million people live or work in the Chesapeake Bay watershed, a drainage basin of 64,000 square miles, encompassing parts of the states of Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the entire District of Columbia.

Human activities over the past 300 years have led to a decline in water quality, mainly due to an increase in nutrients, such as nitrogen and phosphorus, from agricultural and urban runoff. Development has caused a loss of wetlands, forests and shallow water habitats.

"Given the continued growth of Maryland's population, the work of the Tributary Teams and the Coastal Bays Program is critical to developing and implementing strategies to reduce excess nutrients and sediments," said Dr. Magnien.

Bay grasses protect shorelines from erosion by reducing wave action, helping to absorb nutrient pollutants, producing oxygen, and trapping sediments that cloud bay waters. But now bay grass acreage is only a small fraction of what existed historically, primarily due to effects of excessive nutrient and sediment pollution.

These underwater grasses provide food and habitat for threatened crabs, fish and waterfowl. Scientists have found that young blue crabs are up to 30 times more abundant in Chesapeake Bay grass beds then in unvegetated areas.

Since the mid-1990s, scientists have been concerned that the blue crabs in Chesapeake Bay are being overfished. An entire industry -- catering to restaurants featuring crab cakes and steamed crab, and vacationers who come to catch their own, from a boat, a pier or a mud bank, has taken so many crabs that the population is in danger of collapse.

Last September, a panel of scientists and economists reported that blue crab harvests are at record lows, even while the number of crab boats and fishers are at record highs. The breeding population of blue crabs, as well as the overall population, has declined in the bay. Many crabs are being caught at the minimum legal size, as fewer large crabs are found.

The Chesapeake Bay ecosystem is dangerously out of balance, according to the annual 2000 State of the Bay Report released by the Chesapeake Bay Foundation. Despite modest improvements since the 1980s, key bay systems like oysters and underwater grasses are still distressed, nutrient pollution continues to hinder the Bay's overall water quality, and the Chesapeake operates at barely more than a quarter of its historical potential, the group found.

"Habitat restoration and improved fisheries management can take us only so far," said Chesapeake Bay Foundation president William Baker. "Our Achilles heel remains a lack of a comprehensive strategy to reduce pollution from all sources. If we want to save the Bay we must get serious about water quality."

The Chesapeake 2000 agreement, signed by all the bay coastal states, tries to do that. It requires revised nutrient and sediment reduction goals and seeks protection and restoration of the bay's plants, birds and animals and their habitat and the water quality necessary to sustain them. It calls for a revision of restoration goals and a strategy to accelerate restoration of bay grasses.

Even so, this latest Maryland study found bay grasses are still declining in the middle bay area. On the Eastern Shore, Eastern Bay, the Little Choptank, Lower Chester and Lower Choptank rivers all suffered substantial declines, Dr. Mangnien's team found.

These declines were likely due to severe mahogany tides experienced last spring, said Dr. Mangnien. "This algae bloom is caused by excess nutrients and greatly reduces the amount of light reaching the underwater grasses," he said. On the Western Shore, declines in bay grass coverage were evident in the South, Severn, Lower Potomac and Upper Patuxent rivers.

Chesapeake Bay Program acting director Diana Esher said, "It is unfortunate to give back last year's gains in the middle bay, but it's very promising to see that Baywide SAV [submerged aquatic vegetation] is on the rise. Bay Program partners need to redouble our restoration efforts to make sure these trends continue to improve."

One of the bright spots is the large increase in bay grass acreage in the Gunpowder River. In this area, which averaged 200 acres between 1990 and 1995, grass has steadily increased and covered 2,433 acres in 2000. In the tributary Dundee Creek, lush beds of wild celery and elodea grasses carpet the bottom out to nearly eight feet in depth. Large numbers of fish are visible in crystal clear water. The area is surrounded by the forests of Gunpowder State Park, Dundee-Saltpeter Park and Aberdeen.

"The bay grass beds in the Gunpowder River are of particular interest because this area held less than 100 acres in 1989. Now the area holds 24 times as much grass and is home to a great diversity of native species -- both benefits of a forested watershed," said Dr. Magnien. "This area clearly shows the connections between watersheds, water quality and living resources, and is a model for conditions we'd like to see elsewhere."

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