Dead zone seen making a dent in fishing effortsBy Nikki Buskey, Staff Writer
Saturday, August 1, 2009 at 6:01 a.m., HOUMA COURIER
HOUMA — Scientists and fishermen are feeling the effects of this year’s annual Gulf dead zone, which lurks unusually close to the coast.
Even though the area of oxygen-starved ocean is smaller than predicted for this year — 3,000 square miles — it also is closer to the surface than usual.
That’s where the problems for local fishermen especially come into play.
The dead zone’s oxygen-deprivation, known as hypoxia, forms below the mouth of the Mississippi River.
It creates a large area of unproductive waters each summer where marine life is hard-pressed to survive. Bottom-dwelling creatures like shrimp tend to flee for more oxygen rich waters.
But the zone doesn’t sit in one place, said Edward Chesney, a marine researcher with LUMCON. The low-oxygen waters are pushed around as winds and currents change, much to the frustration of shrimpers.
“The trouble with the dead zone is that it will shut you down,” said Dean Blanchard, owner of Grand Isle Seafood, a seafood-processing dock in Grand Isle that serves shrimpers who work offshore in the Gulf of Mexico.
He said that the dead waters will often catch shrimpers unaware, and they’ll trawl for hours in a normally productive spot only to come up with empty nets.
“A guy will be catching 100,000 pounds a day of product and then nothing at all. You don’t known when it’s coming, you got your crew out there, you throw your nets where you normally fish and you get nothing,” said Blanchard.
He estimates losses of $250,000 of his business to last year’s dead zone.
Shrimpers lose out on productive fishing hours and burn up expensive fuel travelling farther to find unaffected waters, Blanchard added.
With this year’s dead zone piled higher, the ‘dead’ water is affecting more marine habitats and animals than usual, said Nancy Rabalais, a top dead zone researcher and director of LUMCON. The dead zone normally only affects bottom waters, and the animals that live there or feed on bottom-dwellers.
This year’s dead zone is encompassing more habitat and seems to be affecting animals that live and feed in middle ocean waters, Rabalais said.
“I saw brown shrimp swimming at the surface. You don’t usually see that,” Rabalais said.
Swimming near the surface is a sign of stress in bottom-dwelling marine animals, and it makes them visible and vulnerable to predators they can usually avoid in their homes near the sea floor.
The dead zone has also pressed closer to the coast, due to wind and current patterns, and earlier this summer may have caused jubilees off Grand Isle. Grand Isle Port Director Wayne Keller said he’s seen ‘an unusual amount’ of fish and crabs pressed close into the shallows off the beach.
“The shrimp are actually jumping on the beach, and tourists are catching them in buckets,” Blanchard said. Sometimes he even sees shrimp leaping onto the Grand Isle beach and dying.
Jubilees are caused when the dead zone, changing winds and currents push great volumes of fish, crabs and shrimp into the shallows along barrier islands.
Though the phenomenon sounds fun, it’s actually a sign of a stressed environment. If the phenomenon goes too far, there also can be what Rabalais calls a ‘jubilee gone bad,’ when the dead zone pushes marine life so close to the shore that marine animals are forced onto the beach and die.
The dead zone can also creep further inland to bays and passes, trapping crabs and crab traps in low-oxygen waters and killing them.
These fluctuations in the dead zone’s shape and location can make it hard to get a big picture of how the dead zone is really affecting fisheries.
But that’s of little comfort to those who are on the edge of it, and see what it can sometimes do.
“We definitely have major concerns with dead zone,” Keller said. “When you’re on the edge of the dead zone you might show a bounty, but all we need is for it to push a little further inland and we’re in it. And with everything affecting the commercial fishing industry right now that’s the last thing we need.”
Staff Writer Nikki Buskey can be reached at 857-2205 or firstname.lastname@example.org