Mattamuskeet, the state’s largest natural lake, is troubled. Its good
vegetation has been depleted while its bad plants are thriving. It has
questionable water quality. It might or might not be too shallow, too
salty and suffering impacts from climate change.
Everyone is worried, but no one can definitely say what’s going on in the lake because little long-term data exists.
the 18-mile long, 7-mile wide lake in Hyde County is the centerpiece of
50,000-acre Mattamuskeet National Wildlife Refuge, money over
the years for studies of water flow, salinity and nutrient levels, fish
stocks and historic rain and flood trends has been inconsistent or
lake attracts thousands of wintering tundra swans, Canada geese,
snow geese, pintails and mallards, as well as less common bald eagles
and ospreys. Of the 800 or so species of wildlife that are found at the
refuge, there are more than 200 bird species that nest there all or
part of the year. The most recent survey in January recorded more than
200,000 ducks, geese and swans on the refuge, a record number,
according to a refuge press release.
the lake is also renowned for its great fishing, especially its notably
huge blue crabs. Much to the chagrin of fishermen, its herring, eel and
largemouth bass fisheries have diminished, and it is not known whether
any one of them is recovering. The lake also has been overrun by
phragmites, an invasive and opportunistic reed plaguing many wetlands
in North Carolina.
address increasing concerns about the health of the lake’s ecosystem, a
meeting was held by the refuge in November to present scientific
information about the water quality, fish and bird species and
management of the lake and canals. In response, a meeting was held in
late January by a group of stakeholders called Save Mattamuskeet Lake.
to 2002, it was world-class bass fishing, “said Mark Carawan, a founder
of the group and an owner of a motel on N.C. 94, which intersects the
lake. “The birdwatchers are even complaining – you can ride across Lake
Road and you don’t see (any) waterfowl.”
said his tackle shop went from selling $10,000 a month of minnows from
March through June 2002, to a total of $300 in those months last year.
group contends that the refuge is mismanaging the flow of water in and
out of the lake, resulting in high salinity, shallow water and poor
conditions for submerged aquatic plants that are critical food for
waterfowl. A big part of the problem, the group says, are the gates
that allow too much brackish water in from Pamlico Sound and too much
fresh water to escape.
want them to replace the gates where the water will stay in the lake
for a certain period of time,” Carawan said, "to be kept at a level
that will sustain the bass fishery.”
Pete Campbell, the refuge manager, said that keeping the lake high
would almost certainly have negative effects and could not even be
considered without further study.
gates on canals between the sound and the lake open and close depending
on the pressure exerted from water levels on each side. The structures
are intended to keep saltwater from coming into the lake and allow
excess water in the lake to be directed to the sound rather than flood
levels fluctuate with wind tides, which create beneficial seasonal
variations in depth, according to a statement from the nonprofit
Friends of Pocosin Lakes. The outflow also removes excessive phosphorus
from the lake, while letting in migratory fish and crabs.
the growing season,” the statement said, “the exposed portions of the
lake green up with grasses and sedges that are critical food for
waterfowl. Meanwhile, even in dry years, most of the lake is deep
enough to support the growth of submerged aquatic vegetation, which is
also eaten by waterfowl.”
less flushing and deeper water, algal blooms are more likely, Campbell
said, because if light can’t reach the bottom of the lake – blocked by
sediment or algal growth -- the plants can’t grow.
on a grandfather clause that has been upheld in court, agricultural
lands surrounding Mattamuskeet are allowed to drain into the lake, the
refuge manager said. It is not entirely understood what, if any,
effect the field runoff has had on water quality, fish populations or
underwater plants. There is not enough data to show the quantity or
quality of the runoff, Campbell said.
“You’ve got herbicides, you’ve got pesticides, you’ve got fertilizers,” he said. “Plus sediment loading.”
is a significant difference between the east and west sides of the
lake, he said, probably because the west does not flush as well due to
unsuitable drainage. About 70 percent of the east side is covered by
underwater plants, Campbell explained. On that side, there are three
canals oriented in the direction of the prevailing wind, promoting
flushing. On the west, only one canal is well positioned to allow
gates in the canals are designed to keep saltwater from coming into the
lake, Campbell said, but there is no capacity to pump water out. In the
past, some of gates had leaked or been clogged with debris.
summer, the lake’s water level, which averages two feet in depth,
naturally drops, Campbell said. The only input is rain and runoff, and
the high evaporation rate is very high.
have high water in the winter and the spring and lower water naturally
in the summer,” Campbell said. “So we don’t manage the lake. The lake
manages the lake.”
2012, the refuge, with the assistance of the U.S. Geological Survey,
has been monitoring salinity on both sides of the lake. Salinity in the
lake proper ranges from 0.4 to 1.5 parts per 1,000, Campbell said,
compared to Pamlico Sound at 16-20 parts per 1,000.
lake has always been not 100 percent fresh,” he said. “There has always
has been a little bit of salinity in the lake. That’s why,
historically, fresh and saltwater species have always been found in the
The dominant submerged plant is wild celery, which likes salinity to be zero or very low, Campbell noted.
the 1980s, Campbell said, the hinged cypress gates were replaced by
unhinged stop log gates. Those were less effective at moving water out
when the lake level was high from rain or pushed up by wind.
Consequently, the lake was unusually high, making boating a lot easier.
They were eventually replaced by metal gates with larger openings.
“They are hearkening back to that time,” he said about the sportsmen who prefer high water.
said there were big negatives to the gate design used in the 1980s and
that the fishing group now favors. During storms, he said, water can’t
move out fast enough, increasing the risk of flooding. And they
cut off access to crabs and herring. The result, he said, was the
herring run crashed and the blue crab population declined.
2010, the refuge put in side gates to promote access for saltwater
species that come into the lake, but especially to improve access for
herring. Ever since then the lake has been able to flush itself, he
said. Crab population rebounded, but additional data is needed to
determine the status of the eel and herring fisheries.
Campbell said the refuge has put together a group of scientists to conduct more study of fisheries and water quality issues.
Stanton, U.S. Fish and Wildlife Service supervisory wildlife biologist,
said that before the 1950s, the lake had a large population of carp
that was the target of a commercial gill net fishery for about eight
years. After the carp were removed, he said, biologists noticed that
the submerged vegetation on the east side had been re-established. Less
than five years later, the musk grass doubled to about 14,000
celery was introduced in the late 1950s, Stanton said. Today it is well
established, along with muskgrass, redhead grass and pond grass. On the
east side, 76 percent of the submerged plants are healthy. On the west
side there is only 13 percent coverage.
markedly different,” Stanton said. “I was out there in 1994. It’s
changed a lot. It was obvious to me that something has been going on in
the last 20 years but noticeably so in the last decade.”
in 1989, he said, the refuge began taking plant surveys every two to
three years, but there was a big gap between 2004 and 2013 because of
cuts in staffing. Stanton said that it’s not clear what has caused the
decrease in underwater plants on the west side but it could be related
to runoff from farm fields and bird impoundments.
along, the management of the refuge, he said, has been hobbled by
budget shortfalls. For instance, much is not known about drainage
patterns and volume, but installation of testing equipment in the
drainage canals would be very costly.
didn’t have those kinds of funds,” Stanton said. “We tried to do the
bare minimum, to do what we had to do. You kind of work with what
said the refuge has got some “rough, crude” information on water
quality but needs quantitative information. The health of the
submerged plants in the lake, he said, serves as a sort of
canary-in-the-coal-mine as to the lake’s overall health.
bottom line is they’re adding nutrients,” he said. “We don’t really
Blythe Davis, a native of Hyde County who has been farming for 37
years, said that the water-quality problems in the lake are largely
caused by people who pump their drainage directly into the lake – which
he does not do.
said that the issue with the water level in the lake comes up every few
years, but proponents seem to be pushing harder now. But if the
water level in the lake is raised, he said it could change the marsh
and cause jurisdictional issues with the Army Corps of Engineers. As it
is now, the lake is barely above sea level.
In the past, Davis said, the high water probably led to algal blooms and depletion of herring and eel.
“They might not get a real good trade-off, he said. “I think that they should leave the gates just like they are.”
Moorman, a hydraulic technician with U.S. Geological Survey, said that
the lake has elevated levels of chlorophyll and nitrogen from
nutrients. “The question is why,” she said. “A lot of nutrients
are in the sediment. So you still might have these issues. You can’t
just cut off the source and expect the problem to go away overnight.”
levels change throughout the year, she said, and are influenced by
numerous factors, including the season, the water temperature and the
layer of water it is measured from. Sources can include animal waste,
fertilizers, septic system leaks and organic matter such as leaves and
County Manager Bill Rich said that the county passed a resolution in
September in support of the refuge’s effort to study restoration of the
lake. But he said he believes that the recreational users are an
important part of the cure.
a Hyde native who has enjoyed crabbing and boating on Mattamuskeet,
said that the lake is the county’s most popular mainland tourist
attraction and is an important revenue producer for the county, one of
the poorest in the state. The lake is “perfectly situated,” he
said, within miles of Fairfield, Engelhard and Swan Quarter, the county
the recent duck hunting season, Rich said, as many as 2,000 hunters
came to the Mattamuskeet area, filling every motel room and every
restaurant seat available.
got to create a situation where the duck hunters are happy, where
there’s fish for the fishermen, birds for the birdwatchers,” he said.
“And that can be done.”
story is provided courtesy of Coastal Review Online, the coastal news
and features service of the N.C. Coastal Federation. You can read other
stories about the North Carolina coast at www.nccoast.org.)
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