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Aug 11, 2010 6:51 PM by Melissa Canone

Marsh Across the LA Coast is Healing Itself

BARATARIA BAY, La. (AP) - Shoots of marsh grass and bushes of
mangrove trees already are starting to grow back in the bay where
just months ago photographers shot startling images of dying
pelicans coated in oil from the massive Gulf oil spill.
More than a dozen scientists interviewed by The Associated Press
say the marsh here and across the Louisiana coast is healing
itself, giving them hope delicate wetlands might weather the worst
offshore spill in U.S. history better than they had feared. Some
marshland could be lost, but the amount appears to be small
compared with what the coast loses every year through human
development.
On Tuesday, a cruise through the Barataria Bay marsh revealed
thin shoots growing up out of the oiled mass of grass. Elsewhere,
there were still gray, dead mangrove shrubs, likely killed by the
oil, but even there new green growth was coming up.
"These are areas that were black with oil," said Matt Boasso,
a temporary worker with the Louisiana Department of Wildlife and
Fisheries.
As crude from a blown-out BP well oozed toward the marshes after
an April oil-rig explosion, experts had feared it would kill roots
in marsh grass, smother the mangroves and ultimately dissolve
wetlands that plant life was holding together. State, federal and
BP cleanup efforts were focused on preventing that from happening
by burning and skimming the oil, blocking it with booms and sand
berms and breaking it up with chemical dispersants.
Whether it is a triumph of cleanup work, the marshes' resiliency
or both, scientists have reported regrowth of grasses, black
mangrove trees and roseau cane, a lush, tall cane found in the
brackish waters around the mouth of the Mississippi River.
"The marsh is coming back, sprigs are popping up," said
Alexander S. Kolker, a marsh expert and coastal geologist in
Cocodrie, La., with the Louisiana Universities Marine Consortium.
He's working with a National Science Foundation team looking at
the effect of the BP oil spill on Louisiana's vast but severely
stressed marshland - also known as the Cajun prairie - where
trappers, shrimpers and alligator hunters have made their living
for generations. Louisiana, the state worst hit by the oil spill,
is home to the vast majority of the northern Gulf's marshland.
Coastal Louisiana is covered in a thick mat of salt marshes that
thrive on the edge of the Gulf of Mexico, where land merges with
the sea. The marshes provide life support for fauna and flora in
the Gulf, said Bob Thomas, a zoologist at Loyola University, and up
to 90 percent of commercial fisheries depend on them for some stage
of fish development.
Young bull sharks, for example, make a beeline for Louisiana's
estuary to feed on catfish, bait fish and crabs, bulking up before
returning offshore to pursue bigger meals, he said.
Many other Gulf species do the same thing. Blue crabs, menhaden
and shrimp all come into the marsh to feed on the nutrient rich
waters of the bays and marshes, where peaceful grazing is easier.
Many freshwater bird species also come down to the marsh to feed,
mature and nest.
Even before the spill, south Louisiana had been losing about 25
square miles of marshland a year, a total of about 2,300 square
miles since the 1930s, mostly due to levee construction, logging,
shipping and oil drilling. Only about 5,300 square miles of marsh
and swamp remain in the state.
Louisiana accounts for about 30 percent of the nation's coastal
marsh and about 90 percent of its marsh loss, according to the U.S.
Geological Survey.
Associated Press calculations based on how much coastline
government scientists say was affected by the oil spill indicate
that at most 3.4 square miles of Louisiana marshland was oiled, an
area stretched out over hundreds of miles of coastline. At least
some of those areas appear to have begun to bounce back.
Ivor van Heerden, a BP-hired environmental scientist, said the
damage may be even less than that. He said federal, state and BP
oil spill survey teams have found only 550 acres of marsh that have
been oiled, less than 1 square mile.
"In all sectors the plants have continued to grow, even in the
very worst areas," he said.
The National Oceanic and Atmospheric Administration concurred
with van Heerden's figure but said it and other federal agencies
are still calculating just how much marsh was oiled and what the
effect has been, said agency spokesman Ben Sherman.
Marshland closest to the Gulf took the worst of the spill,
absorbing oil and keeping it from oozing farther inland. Even
losing a little of it would be a blow to the ecosystem.
Michael Blum, a Louisiana State University biologist who toured
the marsh of Barataria Bay on Tuesday, said some of the grass won't
stick around much longer.
"You're seeing exposed roots," he said. "The expectation is
that you will have loss of the protective sheet, you have marsh
that anchors the marsh in place, and if they die off they no longer
have that anchor."
He added: "There's the possibility that land loss will be
accelerated, or there will be a pulse of land loss associated with
the BP oil spill. The question is how much and where."
Many other questions remain about how much environmental damage
the spill inflicted. Scientists want to understand the effects of
the chemical dispersants BP used to break up the oil and look more
closely at how the smallest forms of life, things like fiddler
crabs and spiders, have been affected.
"This is sort of the initial macroscopic view," said Tom
Bianchi, an oceanographer and marsh expert at Texas A&M University
working with the National Science Foundation team.
He said water from the oiled marsh showed problems. "We did see
some particulates, silts and clays coming out of the marsh,
clogging our filters," Bianchi said. That, he added, was a sign of
marsh death, which could weaken the soil and lead to erosion.
The dominant plant species in coastal Louisiana is the spartina,
better known as smooth cordgrass or salt-marsh cordgrass. Found
from New England to Texas, it can take a beating, which is giving
scientists reason to hope.
"It is used to living in severe environments, salt water and
soils that are completely flooded, and that combination would kill
almost any other plant," said Steven C. Pennings, a University of
Houston ecologist studying the oil's effect on Louisiana's
landscape.
Irving A. Mendelssohn, a coastal plant ecologist at Louisiana
State University, said the wetlands data so far is good news for
fishermen who depend on the ecosystem to produce shrimp, menhaden
and other seafood.
"My gut feeling, based on what I have seen, based on the
recovery people have observed, I doubt that the impact to the
wetlands is going to create a significant problem for our coastal
fisheries," Mendelssohn said.
People in Louisiana know just how vital the wetlands are and how
much they stand to lose.
"The marshes are what I am afraid of," said Kathleen
Barrilleaux, a 57-year-old cafeteria manager at an elementary
school near New Orleans, sitting back in a fold-out chair at the
end of a long day on the pier fishing with her family near
Barataria Bay.
For now, she and her son-in-law, Joseph Breaux, a 41-year-old
grain elevator worker, are upbeat.
"I don't see an oil slick or nothing," Breaux said. His two
daughters and wife were going back and forth on the pier tending to
a fishing line and crab nets.
He said he saw no signs of oil on the crabs they pulled in or on
the croaker fish they caught.
"We're going to have us a crab boil," he said.

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