Chesapeake Bay Journal

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When 17th century explorer George Alsop visited the Chesapeake, he reported that waterfowl so blanketed the Bay that “as they made room for us, there was such an incessant clattering made with their wings on the water where they rose, and such a noise of those flying higher up, that it was as if we were all the time surrounded by a whirlwind.”

Experts believe millions of waterfowl once wintered around the Bay, where they built up their energy reserves by eating underwater grasses, clams and mussels.

Their populations remained high into the mid-1800s, when commercial hunting pressure began increasing to supply food for waves of European immigrants who were used to eating wild game. Hunters used specially designed boats armed with batteries of guns; sometimes a single day’s toll of birds would be in the thousands.

Concern about the dwindling populations grew around the turn of the century, and in 1918, Congress passed the Migratory Bird Treaty Act, which effectively ended the era of commercial waterfowl hunting. Sports hunting continued, but hunters found that the reduced populations of ducks were increasingly skittish around humans. That gave rise to the use of decoys to attract birds, and the creation of increasingly lifelike decoys gradually became a new art form—a craft that continues today with finely carved birds that may never be placed in water.

Waterfowl populations never returned to historic levels. Today, the Bay is home to about 1 million waterfowl in the winter— accounting for about a third of the entire Atlantic Flyway waterfowl population.

The number of birds has remained constant since the 1960s, but the makeup of the wintering population has changed. Duck populations, which tend to rely more heavily on aquatic habitats, have decreased by nearly 80 percent since the 1950s. Geese populations, which can feed away from the Bay in agricultural fields, have increased.

Declines in many of the wintering duck populations can be traced to the loss or degradation of aquatic food sources, such as mussels and underwater grass beds, which are the result of nutrient and sediment pollution.

Many ducks have also been hard hit by the loss of wetland habitat in the prairie pothole region of the upper Midwest where eight of the most common species that winter in the Bay breed. Because of habitat conservation programs, duck production in that region has increased in recent years after decades of decline.

Loss of wetland habitats and encroaching development have also taken their toll around the Chesapeake. Black ducks are in decline because they are particularly intolerant of human disturbance, and rely heavily on underwater grass beds.

Changes in Bay water quality has dramatically affected some species. Canvasbacks once relied primarily on wild celery, an underwater grass, for food. The decline in grass beds forced the canvasbacks to switch from being primarily herbivores to being carnivores as their diet shifted to Baltic clams, a less nutritious food. In the 1950s, a quarter million canvasbacks wintered in the Chesapeake; now about 50,000 winter here—although they remain the Bay’s most abundant duck species.

Redheads, which feed exclusively on grasses but could not switch to other foods, have largely disappeared from the Bay. A few decades ago, as many as 80,000 wintered here; now only a few thousand do so.

The Chesapeake until recently was the most important wintering area for tundra swans in North America, but the population began shifting south into North Carolina—where the population has sharply increased—as underwater grass beds began a sharp decline in the 1970s.

The Bay Program has established a goal of restoring waterfowl populations to 1970s levels. As of 2004, 11 species have achieved that goal and show an increasing population trend. Six have not achieved the goal but are increasing, and 10 have not achieved the goal and are decreasing.

Management efforts to improve waterfowl habitat in the Bay region have focused on wetland protection and restoration, and improving water quality to allow for increases in underwater grass beds.

The Chesapeake 2000 agreement called for restoring 25,000 acres of wetlands by 2010, and to achieve a no-net-loss of existing wetlands through state and federal regulatory programs. In addition, new water quality criteria set for the Bay in 2003 call for returning 185,000 acres of underwater grass beds, up from about 70,000 acres.

Winter Waterfowl Status

Management plans have been established for the 27 species of waterfowl that overwinter in the Chesapeake region. The goal is to restore populations to 1970s levels. Two Bay species are not listed here: The wood duck, a summer resident, overwinters in the Caribbean; the blue-winged teal stops here during its migration. The population of some species have grown so much that they are a problem because they overrun food and nesting areas needed by other waterfowl.

* - recently reclassified as a sea duck ** - formerly called an oldsquaw

Where to Watch Waterfowl

Many Chesapeake Gateways offer a chance to see migratory and resident wildfowl, as well as to learn more about their ecology and about wildfowling traditions such as decoy carving. Use http://www.baygateways.net to find detailed information on how to visit and explore these Gateways:

Eastern Shore

• Elk Neck State Park - North East, MD
• Turner's Creek Park , Sassafras National Resource Management Area - Kennedyville, MD
• Eastern Neck National Wildlife Refuge Area - Rock Hall, MD
• Wye Island Natural Resources Management Area - Queenstown, MD
• Chesapeake Bay Environmental Center - Grasonville, MD
• Chesapeake Bay Maritime Museum - St. Michaels, MD
• Blackwater National Wildlife Refuge - Cambridge, MD
• Ward Museum of Waterfowl Art - Salisbury, MD
• J. Millard Tawes Museum and Ward Brothers Workshop - Crisfield, MD
• Eastern Shore of Virginia National Wildlife Refuge - Cape Charles, VA

Western Shore

• Havre de Grace Decoy Museum - Havre de Grace, MD
• Patuxent Research Refuge, National Wildlife Visitor Center - Laurel, MD
• Merkle Wildlife Sanctuary and Visitors Center - Upper Marlboro, MD
• Patuxent River Park, Jug Bay Natural Area - Upper Marlboro, MD
• Flag Ponds Nature Park - Lusby, MD
• Hoffler Creek Wildlife Preserve - Portsmouth, VA