05/25/10

Gulf Coast Wetlands Threatened by Oil Spill

We’ve abandoned our amphibian friends for a couple of weeks to write about the Gulf Coast Oil spill, and while I’d hoped to get back to them this week, the latest news about the oil washing up and covering wetlands seemed too important for us to ignore. And it is an issue that relates to amphibians. While few amphibians live in salt-water wetlands, fresh-water wetlands are vitally important to them.

Wetlands are some of the most environmentally productive ecosystems on earth. Some common names for wetlands are marsh, swamp, or bog. To be called a wetland, an area must be soaked with water for part of the year. Louisiana’s wetlands wind through shallow estuaries, inlets, bays, and reefs. So what’s the big deal about these wetlands?

  • Wetlands provide a habitat for a large variety of wildlife and plants
  • Wetlands are a nursery area for fish, shrimps, crabs, oysters and other wildlife—a calm area protected by heavy waves.
  • Wetlands are like a kidney for other ecosystems, filtering out, cleaning, and storing water.
  • Migratory birds nest in the wetlands

What Oil Does to Wetlands

The glue that holds the marsh together is grass. If grasses are repeatedly covered with oil, they will suffocate. It may take years for intertidal salt marshes and sea grass beds to recover from this kind of oiling.

Oil in Louisiana wetlands, copyright Ted Jackson/The Times-Picayune on nola.com

As quoted by Irving Mendelssohn, a Louisiana State University botanist who specializes in wetland plants, in an AOL News article, “Once they’re dead, the soil collapses,” he said. “Then the soil becomes flooded and can’t grow back. The low areas that become ponds, the ponds form lakes and then the wetland disappears.”

How can the marshes be saved? Some suggestions include burning the oil-covered plants, low-pressure flushing, which helps push oil into areas where it can be vacuumed up or absorbed, cutting back vegetation to leave plants intact, and adding nutrients to help speed to degradation of the oil. Louisiana Governor Bobby Jindal has suggested dredging sand from the Gulf of Mexico and building islands to stop the oil from reaching wetlands. None of these methods is considered ideal and all have potentially serious environmental repercussions.

Even if people don’t care about wildlife and biodiversity, they should be concerned about the destruction of the wetlands. Almost all of the sea life that we consume from the Gulf of Mexico begins its life in these sea grass beds and wetlands. Also, the wetlands provide a buffer for storms and hurricanes, absorbing wind and tidal forces—of vital importance in this hurricane-prone area.