Defenders' Experts
Blackwater National Wildlife Refuge - Maryland
Thirty-five percent of all the waterfowl that travel the Atlantic Flyway spend the winter on the Chesapeake Bay, thousands of them in the marshes of Blackwater National Wildlife Refuge. At the refuge, fresh water meets salt water to form the productive brackish wetlands where ducks and geese find cold-weather sustenance. The refuge also harbors the largest nesting concentration of bald eagles on the East Coast north of Florida.
The Threat
Aerial photographs taken over the last five decades reveal another notable fact about Blackwater National Wildlife Refuge: It is rapidly disappearing. During the past century, more than a third of Blackwater's wetlands have been submerged as sea levels in the Chesapeake Bay region have risen by one foot and temperatures by 4 degrees F. According to the Environmental Protection Agency, compared to 1990 levels, the Chesapeake Bay area could experience an 8 inch rise by 2025, a 13 inch rise by 2050 and a 27 inch rise by 2100. If this warming trend and other landscape-altering processes persist, most of the refuge's remaining wetlands will be gone in 30 years.
As temperature and precipitation rise, flooding, caused by frequent coastal storms, will become more common. Increased runoff into the bay can lead to lower water quality and decreased dissolved oxygen. This can lead to high nutrient levels in the bay and outbreaks of toxic organisms such as Pfiesteria piscicida, which scientists believe contributed to a massive number of Chesapeake Bay fish deaths in 1997.
For every 1 degree Fahrenheit the water warms, the Chesapeake Bay's capacity to dissolve oxygen decreases by 1.1%. Without life-sustaining oxygen, the Bay's fisheries will be under increasing stress.
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