Efforts combined to save reefs
Published 10:25 pm Thursday, April 1, 2010
Take two hurricanes named Ivan and Katrina and add three years of drought. What those add up to is a disaster for Alabama’s oyster reefs.
The crashing storm surges from the hurricanes displaced many of the oysters from the reefs. The subsequent drought then wrought more havoc by allowing the water salinity to increase to a level that would sustain the dreaded oyster drill, a tiny snail that resembles a baby conch capable of drilling a hole in an oyster shell and killing the oyster.
Instead of letting nature taking the slow route to recovery, Alabama is hoping to vastly speed up the process with the combined effort – dubbed the “Oyster Relay” – of the state’s oystermen and the
Alabama Department of Conservation and Natural Resources (DCNR) with the assistance of federal money from Katrina recovery funds.
The relay is a huge undertaking to transfer 100,000 bushels of oysters from upper Mobile Bay, where oystering has been closed for many years for water quality reasons, and moving the tasty mollusks to a new reef about 2.5 miles south of the mouth of East Fowl River. Tongers are taking oysters from a shallow-water reef to the north, while dredges are being used to gather oysters in deeper water. The oysters are then loaded onto barges and transferred to the new reef.
John Mareska, marine biologist the DCNR’s Marine Resources Division, said the impetus for the relay was decline in oyster harvest to only 72,266 pounds in 2008, the third-worst harvest since the record-keeping started in 1950.
“What caused us to consider this were Hurricane Katrina and the subsequent drought,” Mareska said. “That combination really put the reefs in decline. This is something Mississippi had done and we had the financial resources through the Emergency Disaster Relief Program, what a lot of people call the Katrina funds. Based on that combination of factors, we thought, yeah, let’s try it.
“Ivan actually did more damage than Katrina. Ivan was the first blow, Katrina the second blow and the final knockout was the drill. It was a one-two-three punch, so to speak.”
During the drought years that followed Katrina a diminished river flow allowed an increased saltwater intrusion into the estuaries and rivers, which translates into ideal conditions for the destructive oyster drill.
“During the drought, people were catching red snapper in the Mobile River,” Mareska said. “Plus, we had very mild winters. Cold is another thing that will drive drills away and kill them. So we had warm, dry winters that really allowed the drills to stay where they were and decimate the reefs.”
Mareska said Marine Resources does annual assessment dives on the oyster reefs to judge their health and it didn’t take much research to determine the reefs were in trouble.
“We look at spat (oyster larvae) abundance, harvestable size oysters and we even keep drill counts to keep track of that,” he said. “We could see this coming. But unless you know how to make it rain, there’s not much you can do about it.”
On Buoy Reef, the deepest of Alabama’s reefs and most susceptible to the drills, there were 30 samples taken in 2006 that had more than 1,000 spat. By August 2007 the spat number plummeted to 13. Small oysters went from over 400 down to zero during that time period. In August 2009 sampling indicated 18 spat but still zero small oysters and no harvestable size oysters.
The silver lining from the drought years was that water conditions greatly improved on the upper end of Mobile Bay, where the oyster reefs had been closed for many years.
“A lot of the oystermen can remember going out and harvesting oysters in the upper bay when they were much younger,” Mareska said of the reefs that were shut down by the Alabama Department of Public Health because of unfavorable water conditions “These reefs were left alone, but an oyster can reach harvestable size in 18 months. When conditions down the bay became unfavorable because of the drills, conditions up the bay became real favorable for oysters to grow.
“Basically, we took water conditions off Cedar Point and moved them up the bay, at least Mother Nature did. It was optimal for oysters to grow up there. That happened for three years. We knew there were already oysters up there. But because oyster harvest is prohibited we couldn’t do anything with them.”
Mareska said the 100,000 sacks, which includes oysters and culch material (relic oyster shells and clam shells), were not moved to Whitehouse Reef. Instead a reef closer to the western shore was chosen for the relocation.
“There is a dissolved oxygen (DO) problem on Whitehouse Reef,” he said. “When the bay stratifies it causes the DO problem and the oysters die. That’s why we moved them closer inshore and put them in water 4-8 feet deep. We put them in a location where there should not be a DO problem.”
The new reef with a total area of about 800 acres will be marked with pilings. The current project will cover about 70 acres of the reef with oysters and culch with additional material added when funds are available.
“We’ve received a lot of positive feedback,” Mareska said of the relay. “They say it’s a great program. They are excited to see all those oysters. They had no idea the volume of oysters up the bay.”
Bayou La Batre Mayor Stan Wright, who is also in the seafood business, signed on as Marine Resources’ oyster consultant last year and is heavily involved in the relay.
“This is a definitely a blessing for the state of Alabama,” Wright said. “But I don’t want any of the credit. I want Governor (Bob) Riley, Conservation Commissioner (Barnett) Lawley, Vern Minton (Marine Resources Director) and John Mareska to get the credit. First of all, they identified we had a major problem. It’s no different from raising a crop. You’ve gotta have equipment. I came up with a short-term plan and a long-term plan. The short-term plan was to use some Katrina money to benefit the fishermen by letting them plant the shells to enhance these reefs with culch. We planted about 300 acres of dried oyster shell last June. Now the oysters on it are about as big as 50-cent piece. But it takes about two years for these oysters to grow big enough, which means it’s really a long-term plan.
“So another part of the short-term plan was to relay oysters from up the bay to more acceptable water conditions and put these fishermen to work quick.”
Wright said he would closely monitor the new reef to make sure the site is developing as planned before any oystermen are allowed on the reef.
“We’ll be checking mortality rate and for new spat to make sure they’re going to sustain themselves,” he said. “We made sure they’re on hard bottom so they wouldn’t sink in the bottom. We’ll be sampling on a weekly basis to make sure things are up to par.
“If everything goes as planned, my recommendation with be that by the first of October we allow these people to harvest these oysters to put them on the market for human consumption.”
The river stage at Barry Steam Plant must be below 8 feet for at least 21 consecutive days before Alabama’s oyster reefs are open for harvest. Conceivably, the new oyster reef could be opened before October, but Wright wants to proceed with caution.
“I want to give these oysters enough time to get back in their feeding habits to build the body weight they need to survive, plus spawn this spring to produce more oysters for the lower reefs,” he said. “If we move them today and go catch them tomorrow, we haven’t really done much.
“And this is also going to help the reefs that we’ve relayed from by cultivating them, removing the silt and bringing up new shells. We’re watching this real close. We don’t want to overharvest or damage these reefs in any way.”
Wright also said the new reef will benefit more than just oystermen and oyster consumers.
“The reef we’re building is in shallow water – 4 to 6 feet deep,” he said. “It’s going to be one of finest speckled trout reefs you’ve ever seen in your life. So it’s also enhancing the sportfishing industry.
“I know it’s been a great economic boost for our community.”