Federal report: Rapid loss of coastal wetlands harming important waterfowl areas

11/23/2013 | 0

NC-coast-after-Irene

In 2011, Hurricane Irene cut new inlets along the North Carolina coast in Pea Island National Wildlife Refuge. Coastal storms can damage wetlands through erosion, washing in sediments, or by increasing salinity. Photo by Tom MacKenzie/U.S. Fish and Wildlife Service

The United States is losing more than 80,000 acres of coastal wetlands each year, according to a report released by the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration. The study assessed coastal wetlands along the Atlantic, Pacific, Gulf, and Great Lakes coasts from 2004 to 2009.

The highest losses were recorded along the Gulf coast (257,150 acres). They accounted for 71 percent of the total estimated loss during the study period. Ducks Unlimited noted that the “losses continue to erode capacity for coastal Louisiana and Texas to support waterfowl in the most important wintering area on the continent.”

“In coastal Louisiana,” said Tom Moorman of DU’s southern region, “we’ve lost so much coastal marsh since the 1970s that today’s available habitat supports an estimated three million fewer ducks.”

Along the Atlantic coast, 111,960 acres were lost, while the Pacific coast lost 5,220 acres. The watersheds of the Great Lakes region experienced a net gain in wetland area of an estimated 13,610 acres.

“When a study shows that an area four times the size of Miami is disappearing every year, it underscores the importance of strengthening our collective efforts to improve wetlands management, to reduce losses, and to ensure [that] coastal infrastructure and resources are protected,” said Interior Secretary Sally Jewell.

FWS Director Dan Ashe noted that coastal wetlands provide habitat for 75 percent of the nation’s waterfowl and other migratory birds. “We can’t sustain native wildlife for future generations without protecting and restoring the coastal wetlands that support them,” he said.

The recent losses were attributed to coastal storms, urban and rural development, and some forestry practices. In certain coastal watersheds, the study says, rising ocean levels are encroaching into wetlands from the seaward side, while development from the landward side takes a further chunk out of the existing wetland area and prevents wetlands from being able to migrate inland. This dual threat squeezes wetlands into an ever-smaller and more fragile coastal fringe.

Altogether, the report estimates that 360,723 wetland acres in coastal watersheds were lost during the study period, or 0.9 percent of the 41.4 million acres that existed in 2004.

While the percentage of the decline is fairly small, the report’s authors, Thomas E. Dahl of FWS and Susan-Marie Stedman of NOAA, note that the federal government’s two-decade-old policy of no-net loss of wetlands, initiated by President George H.W. Bush in 1989, is not working.

“A strategy of achieving ‘no net loss’ by offsetting wetland-acreage losses with wetland creation or reestablishment,” they write, “does not appear to be effective in the coastal watersheds.” — Matt Mendenhall, Managing Editor

Read the report

T.E. Dahl and S.M. Stedman. 2013. Status and trends of wetlands in the coastal watersheds of the Conterminous United States 2004 to 2009 (PDF). U.S. Department of the Interior, Fish and Wildlife Service and National Oceanic and Atmospheric Administration, National Marine Fisheries Service (46 pages).