Gulf Coast Wetlands Rapidly Declining

Ryan Fikes | Last Updated: December 23, 2015

The Gulf of Mexico is losing more wetlands than anywhere else in the United States and it is losing them more rapidly than ever before, according to a new federal report that assessed the status of wetlands in the United States.

vertical Apalachicola Bay_Flickr_McClammalIV — Sunset across Apalachicola Bay. Flickr photo courtesy of McClamma lV.

The Significance of Wetlands

Why is this loss of this particular type of habitat so devastating? According to the lead author of the report, Tom Dahl, the effects are far-reaching:

“You lose places for those organisms to breed, feed, rest,” Dahl said. “You’re losing some capability for other environmental functions like filtering pollutants, providing some protection from storm damage.

“You’re losing recreational opportunities for bird-watching and canoeing. You’re affecting hydrology. The areas are no longer able to retain water. The hydrology is changing and we don’t recognize what the full implications are,” he said.

The Gulf’s Wetlands

The Gulf Coast is home to more than half of all saltwater wetlands in the country and the Gulf region also contains nearly 35% of the nation’s freshwater wetlands. Both types of wetlands are disappearing rapidly: there was a 25 percent increase in the rate of coastal wetland loss from the previous five-year period. The losses in the Gulf region were massive—257,150 acres of wetlands disappeared in total. That’s seventy-one percent of the total wetlands lost nation-wide.

The Vanishing Mississippi River Delta

Nowhere in the United States is losing wetlands faster than the Mississippi River Delta, the region where freshwater from the Mississippi River meets the Gulf of Mexico. Over the past eighty years, this ecologically important region has lost an area of fresh and saltwater wetlands as large as the state of Delaware. And the delta continues to disappear at an astonishing rate: an average of a football field of land is lost every hour.

Wetlands Trends Figure 1 — Wetland gains and losses in the coastal watersheds of each coastal region between 2004 and 2009. Figure courtesy of NOAA/USFWS.

Many factors have led to the delta’s collapse. One of the most significant is that the lower Mississippi River has been straitjacketed with levees as part of a national program to “control” the Mississippi and protect communities from flooding. But the delta’s wetlands are built and sustained by sediment delivered by the river. A vast network of shipping channels exacerbate the problem by allowing saltwater to penetrate deep into the wetlands, killing the vegetation in freshwater wetlands, and ultimately causing them to subside underwater.

Wetlands Trends Figure 2 — Coastal watersheds of the upper Gulf of Mexico showing the magnitude of saltwater (intertidal) wetland loss to open water, 2004 to 2009. Figure courtesy of NOAA/USFWS.

In 2005, Hurricanes Katrina and Rita devastated the region. The damage these two hurricanes wrought was made worse by the previous loss of miles of protective wetlands. Much of the wetlands lost during the period in this study can be attributed to these two hurricanes.

Where do we go from here?

This study makes it clear that we need to do all we can to protect and restore wetlands across the country and particularly in the Gulf of Mexico. One year after the study ended, the BP oil disaster further affected the Gulf’s wetlands, particularly in the Mississippi River Delta, but elsewhere as well.

The RESTORE Act, which sends money from BP’s Clean Water Act fines back to the five Gulf States, gives us the opportunity to move the needle on these critical habitats and improve habitats and water quality in the Gulf of Mexico.