Mississippi River floods destroy oyster grounds. (Photo: dmr.state.ms.us/FIS)
Mississippi River floods threaten oyster grounds
Wednesday, May 11, 2011, 00:30 (GMT + 9)
Oyster fishers in the south are not only still rebounding from last year’s BP oil spill but are also now bracing for major floods that could destroy the few remaining oyster grounds as the Mississippi River overflows. The river, which runs from Minnesota down to the Gulf of Mexico, has been causing floods along the Midwest and South of the US for weeks.
The Corps of Engineers opened a spillway this week and may open others to protect areas close to the river, allowing the diverted freshwater to ease pressure on levees -- but the measure will also send freshwater into the salty waters where the oysters dwell, which might kill them.
Apart from the Bonnet Carre Spillway about 30 mi northwest New Orleans, Louisiana (LA), the Corps may open the Morganza Spillway some 35 mi northwest of Baton Rouge, reports Daily Comet.
If the Corps opens the Morganza spillway “from the Houma Navigation Canal going westward, we could see 100 per cent oyster mortalities,” warned Mike Voisin, owner of Motivatit Seafood in Houma, LA and a member of the state's Oyster Task Force. “Two of the major areas propping up the oyster industry right now will be significantly impacted.”
When freshwater diversions on the east and west sides of the Mississippi River were opened last year to try and keep the BP oil spill from oozing into wetlands, the water killed up to 80 percent of an oyster crop that had just finished spawning. Those grounds are still recovering, Voisin commented.
Experts say the damage from the flood control actions will push the oyster industry back another year or longer.
"It has the potential to create an imbalance that we have never seen before," said Joe Jewell with the Mississippi Department of Marine Resources. "As a consequence, it will have a dramatic effect on the seafood and life forms in our marine environments."
He believes that releasing more water could wipe out South Mississippi's oyster and shrimp industries, among others, reports WLOX.
Harry Blanchet, a biologist for the Louisiana Department of Wildlife and Fisheries (LDWF), said mortality rates depend on how long a spillway remains open and how much water is allowed through.
The Bonnet Carre Spillway may be open for two to four weeks, said Corps spokesperson Rachel Rodi, but some people believe it could be open until July.
It takes three to five years for devastated oyster crops to bounce back, Voisin said.
“Mother Nature gives, and she takes away,” Voisin said. “But I'm beginning to believe ... that maybe this is the straw that breaks the camel's back. This flood is going to potentially break a few backs.”
- Louisiana oyster industry struggling the most
- BC oyster farmers unable to help those in Gulf of Mexico
By Natalia Real