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NOAA WORKING TO RESTORE OYSTERS IN THE CHESAPEAKE BAY
March
31, 2005 — Just off the bow, as the cabin cruiser cautiously nudges
through wavelets stirred by a brisk March breeze, the untrained eye can
make out faint café au lait blotches just under the surface, in
contrast to the darker surrounding water of the Great Wicomico River in
Virginia.
Though you wouldn’t know it to look at them, the spots may represent the beginning of an ecological comeback for Chesapeake oysters and eventually for the Bay as a whole.
“This is what the Chesapeake Bay used to look like,” says Tommy Leggett, who simultaneously sees the Bay through the eyes of scientist (he holds a master’s degree in marine science) and a working waterman. “You’ve heard of the coral reefs in the Florida Keys? This is the Chesapeake Bay equivalent.”
The
blotches are the tops of artificial oyster reefs which rise from the riverbed
to just below the lapping waves. These Great Wicomico reefs are destined
to provide homes for millions of young, specially bred oysters that, it
is hoped, will not only be strong enough to resist diseases that have
ravaged the bivalve population for nearly 50 years, but to thrive and
reproduce.
Scattered in several locations along the river bottom, the reefs represent, if not the hope of an immediate return to the Bay’s past glories as one of the world’s premier oyster habitats, then at least a milestone along the road to recovery.
Disease and other harmful influences strike reefs around the world. But here in the Chesapeake, centuries of harvesting pressures and persistent diseases have reduced what was once one of the world’s most bountiful oyster-producing waterways into a virtual underwater wasteland in less than a human lifetime.
The restoration work here represents one facet of a new and concerted effort by federal and state governments, non-profit organizations and watermen to reverse the damage.
NOAA
is involved in several ways in the restoration effort.
Through its Sea Grant Oyster Disease Research Program, NOAA supports a selective breeding program to produce disease resistant oysters. Eight strains of disease resistant shellfish have been developed so far. One of those strains, known as Disease-Resistant Delaware Bay Oysters (also known as DEBYs) was used to seed the reefs in the Great Wicomico.
In 2004 and 2005, the NOAA Chesapeake Bay Office received a total of $2 million in congressionally earmarked funds to carry out scientific monitoring of the efforts to seed the oyster reefs in the river by the U.S. Army Corps of Engineers Norfolk District Office. CBO provides technical expertise to the project though oyster-restoration expert Rick Takacs also has a contract with the Virginia Institute of Marine Science to monitor the restoration effort. VIMS provides the data it collects to CBO.
“NOAA is excited to be a partner with these other agencies on oyster restoration activities. We are eager to see results from the Great Wicomico project that we can apply to other areas in the Chesapeake Bay,” said Paula Jasinski, fishery biologist with NOAA's Chesapeake Bay Office. “The native oyster has been a critically important species to both the health and the commerce of our Bay, which is why we continue to make substantial investments of time and money on innovative restoration approaches."
Protecting,
restoring, and managing the use of ocean, coastal and Great Lakes resources
is one of the goals of NOAA’s
strategic plan for the next five years.
NOAA’s
other partners in the Great Wicomico initiative effort include the U.S.
Environmental Protection Agency, the U.S. Fish & Wildlife Service,
the Virginia Marine Resources Commission, the non-profit Chesapeake Bay
Foundation and the Sarah’s Creek Shellfish Co.
“Sustainable ecosystem” Goal
In
early March, the partners began an ambitious effort to seed the 3.8-acre
zone of artificial reefs, constructed on materials taken from Virginia’s
James River, with the first of some 15 million oysters slated to be settled
there.
In
time, it is hoped, those oysters will live, spawn and, eventually, thrive
in the Great Wicomico, each incrementally improving water quality by filtering
out enormous amounts of sediments and other materials. Although the oyster
was once one of the Bay’s major “cash crops,” restoration
of commercial harvesting is not the project’s goal.
Dan Bacot Sr., a marina owner and the founder of the Sarah’s Creek Shellfish Co. who has a contract with the U.S. Corps of Engineers to provide young oysters for the project, has just returned from a morning of seeding the Great Wicomico. Holding a dripping and muddy handful of small seed oysters out to be examined by visiting reporters, he reinforces the notion that habitat restoration is what he and the other partners in the venture are about. “A sustainable ecosystem is our measure of success,” he says.
“The oyster is literally the foundation of the ecosystem. What we’re after is the mature oyster. Each mature oyster filters 50 gallons of water a day. You do the math,” adds Doug Martin, manager of the Corps’ Chesapeake Bay native oyster restoration project, as he points to baskets of oysters stacked on Bacot’s boat. “This is the breeding stock here. Their offspring and their off-spring’s off-spring, we hope, will provide the biomass” for a healing ecosystem."
A
New Beginning?
Like
the Bay itself, the Great Wicomico is an estuary, a body of water where
salt and fresh water mix. But the river is also what is called a “trap
estuary,” because oyster larvae are trapped in the river by its
circulation. In other words, the Great Wicomico is a relatively small,
sheltered waterway ideal for the project’s needs.
“In effect, we’re using these small estuaries as gigantic natural hatcheries,” said Standish K. Allen, Jr., a professor of marine science at VIMS, who runs the institute’s selective breeding programs.
In early March, Leggett and Amy Blow, both scientists with the Chesapeake Bay Foundation’s Virginia Office, worked their skiff alongside Bacot’s boat, dumping oysters from colorful plastic laundry baskets over the side where they eventually settle on the reefs below.
Although
hard for an observer to credit, the 18 baskets on Blow and Leggett’s
open boat contained roughly 9,000 oysters. Bacot’s crew, meanwhile,
seeded several hundred thousand oysters in their day’s work.
The sheer numbers alone were impressive, but not, by themselves, enough to ensure success for the project, Allen noted.
Large numbers of oysters probably exist in the river already, but the population is widely spread out and, like all Bay oysters, susceptible to MSX and Dermo, the two diseases that have contributed to the near collapse of Bay oystering.
“I’m sure there are 15 million oysters here already,” said Allen. “The question is ‘are they close enough together to effectively reproduce?’ Furthermore, a sick oyster is not a good reproducing oyster.”
In addition to monitoring the overall outcome of the restoration project, VIMS’s role in the restoration project has been to produce selectively bred oysters that are not only disease resistant, but also genetically unusual enough to stand out from the wild populations.
The disease resistance is expected to give the oyster perhaps an additional year of reproductive life, which over time, as more and more oysters are spawned, could enlarge and strengthen the currently almost negligible reproductive rates.
Throughout the Bay, “generally speaking, the oyster population is so low that natural [reproduction] is not occurring,” notes Martin.
However, the ability to identify a genetically unique group of animals in the future will also allow scientists to separate out improved spawning by the domesticated oysters from any general patterns of reproduction by wild Great Wicomico oysters.
“They will allow us to ‘ground-truth’ that the oysters we are putting on a reef are actually making a difference,” says Allen.
Almost
everyone involved in the project agrees that what Martin dubbed the “sustainable
ecosystem” approach to restoration of the Great Wicomico is a venture
into uncharted waters that will require “adaptive management”
techniques to succeed. Last
year, for example, an unexpected influx of cow-nosed rays ate huge numbers
of young oysters in an artificially seeded bed in the Great Wicomico.
This year, the Corps is taking steps to keep the predators away from the
young oysters.
Through its contract with NOAA, VIMS will play a key role in the adaptive management approach by providing an independent, scientifically objective review of every step taken to restore the Great Wicomico.
If
successful, the project promises a long-term approach to restoring the
health of a national asset.
New approaches
like those being tried in the Great Wicomico may just be what are needed
to truly turn the tide for the Bay and those who enjoy it or depend on
it for their living, notes Leggett.
He acknowledged that he and other watermen in his boat weren’t above
recognizing the irony as they threw the baskets of seedlings into the
water. “That’s the culmination of a year’s worth of
work. In three minutes’ time, they’re on the bottom,”
he said with a grin. “We weren’t taught to toss ‘em
back overboard. We were taught to keep them in the boat.”
Relevant
Web Sites
NOAA
Dignitary Recognizes Accomplishments of Oyster Restoration in South Carolina
on Earth Day 2004
NOAA AWARDS $1.4 MILLION TO IMPROVE OYSTER RESOURCES IN LOUISIANA
NOAA AWARDS $1.7 MILLION TO RESTORE OYSTER RESOURCES IN FLORIDA
NOAA
AWARDS $4.3 MILLION TO RESTORE OYSTER RESOURCES IN ALABAMA
Media
Contact:
Jana
Goldman, NOAA Research, (301)
713-2483 or Peter West, NOAA
Research, (301) 713-2483