Huge, once-hated fish now seen as weapon against Asian
carp
July
29, 2016 by Tammy Webber
Link To Original Story: http://m.phys.org/news/2016-07-huge-once-hated-fish-weapon-asian.html#
In this July 6, 2016 photo, U.S. Fish and Wildlife Service
personnel struggle with carrying an adult alligator gar to a transportation
tank at the Private John Allen National Fish Hatchery in Tupelo, Miss.
Alligator gar can weigh several hundred pounds and be over eight feet long.
Several male and female adult alligator gar are captured in fresh water lakes
and rivers and are brought to the facility so they can lay and fertilize the
eggs as biologists and environmentalists are working to reintroduce the once-reviled
alligator gar as a weapon against another huge species: invasive Asian carp.
The gar are later returned to the wild. (AP Photo/Rogelio V. Solis)
It's a toothy
giant that can grow longer than a horse and heavier than a refrigerator, a
fearsome-looking prehistoric fish that plied U.S. waters from the Gulf of
Mexico to Illinois until it disappeared from many states a half-century ago.
Persecuted by
anglers and deprived of places to spawn, the alligator gar—with a head that
resembles an alligator and two rows of needlelike teeth—survived primarily in
southern states in the tributaries of the Mississippi River and Gulf of Mexico
after being declared extinct in several states farther north. To many, it was a
freak, a "trash fish" that threatened sportfish, something to be
exterminated.
But the
once-reviled predator is now being seen as a valuable fish in its own right,
and as a potential weapon against a more threatening intruder: the invasive
Asian carp, which have swum almost unchecked toward the Great Lakes, with
little more than an electric barrier to keep them at bay. Efforts are now
underway to reintroduce the alligator gar in the northern part of its old
range.
"What else
is going to be able to eat those monster carp?" said Allyse Ferrara, an
alligator gar expert at Nicholls State University in Louisiana, where the
species is relatively common. "We haven't found any other way to control
them."
In this June 13, 2012 file photo, Asian carp, jolted by an
electric current from a research boat, jump from the Illinois River near
Havana, Ill. An effort is under way to reintroduce alligator gar into lakes,
rivers and backwaters of several states possibly to help control populations of
the invasive carp. (AP Photo/John Flesher, File)
Alligator gar,
the second-largest U.S. freshwater fish behind the West Coast's white sturgeon,
have shown a taste for Asian carp, which have been spreading and out-competing native
fish for food. The gar dwarf the invaders, which themselves can grow to 4 feet
and 100 pounds. The largest alligator gar caught was 8 ½ feet and 327 pounds,
though they can grow larger.
Native Americans
once used their enamel-like scales as arrow points, and early settlers covered
plow blades with their tough skin and scales. But a mistaken belief that they
hurt sportfish led to widespread extermination throughout the 1900s, when they
were often shot or blown up with dynamite.
"Some
horrible things have been done to this fish," said Ferrara, adding that
sport fisheries are healthier with gar to keep troublesome species like carp
under control. "It's similar to how we used to think of wolves; we didn't
understand the role they played in the ecosystem."
In this July 6, 2016 photo, U.S. Fish and Wildlife Service
fish biologist Daniel Schwarz, left, maintenance mechanic Ronnie Schutkesting,
release an alligator gar in a special transportation tank at the Private John
Allen National Fish Hatchery in Tupelo, Miss. Several male and female adult
alligator gar are captured in fresh water lakes and rivers and are brought to
the facility so they can lay and fertilize the eggs as biologists and
environmentalists are working to reintroduce the once-reviled alligator gar as
a weapon against the invasive Asian carp. The gar are later returned to the
wild. (AP Photo/Rogelio V. Solis)
Gar now are being
restocked in lakes, rivers and backwaters—sometimes in secret locations—in
several states. In May, Illinois lawmakers passed a resolution urging state
natural resources officials to speed up its program and adopt regulations to
protect all four gar species native to the state.
But the extent to
which gar could control carp now is not well understood, and some people are
skeptical.
"I don't
think alligator gar are going to be the silver bullet that is going to control
carp, by any stretch of the imagination," said Rob Hilsabeck, an Illinois
biologist who says the best hope is that carp will sustain an alligator gar
fishery to draw trophy hunters.
In this July 6, 2016 photograph, an adult alligator gar
awaits placement into a transportation tank at the Private John Allen National
Fish Hatchery in Tupelo, Miss. The gar's easily identifiable head resembles an
alligator and has two rows of needlelike teeth. This is one of several male and
female adult alligator gar that are captured in fresh water lakes and rivers
and are brought to the facility so they can lay and fertilize the eggs as
biologists and environmentalists are working to reintroduce the once-reviled
alligator gar as a weapon against the invasive Asian carp. The gar are later
returned to the wild. (AP Photo/Rogelio V. Solis)
Others are more
optimistic about the impact once the larger fish is established, which might
require cutting notches in canals to give them access to spawning sites.
Asian carp
reproduce more quickly but alligator gar also grow fast: Alligator gar stocked
in one Illinois lake six years ago already are more than 4 feet long.
Quinton Phelps, a
Missouri state fish ecologist, said the only way to effectively control carp is
when they're smaller, before they can spawn. Which is where alligator gar come
in.
In this July 6, 2016 photo, U.S. Fish and Wildlife Service
personnel struggle with the nets as adult alligator gar try to escape as their
small pond is seined at the Private John Allen National Fish Hatchery in
Tupelo, Miss. Several male and female adult alligator gar are captured in fresh
water lakes and rivers and are brought to the facility so they can lay and
fertilize the eggs as biologists and environmentalists are working to
reintroduce the once-reviled alligator gar as a weapon against the invasive Asian
carp. The gar are later hand caught and returned to the wild. (AP Photo/Rogelio
V. Solis)
"There is
potential for them to be a wonderful weapon, but it's just potential right
now," he said.
One challenge is
that huge gar could become a temptation for trophy fishermen, even before
they're old enough to spawn.
"It will be
interesting to see if fishermen have enough integrity to pass up a 7-foot fish
that's 200 pounds," said Christopher Kennedy, a Missouri fisheries
supervisor who's working on catch regulations. "We'd love to create a
self-sustaining population that we can turn into a trophy fishery."
In this July 6, 2016 photo, small alligator gar swim in one
of several tanks where their growth is monitored as the U.S. Fish and Wildlife
Service personnel raise them at the Private John Allen National Fish Hatchery
in Tupelo, Miss. Several male and female adult alligator gar are captured in
fresh water lakes and rivers and are brought to the facility so they can lay
and fertilize the eggs as biologists and environmentalists are working to
reintroduce the once-reviled alligator gar as a weapon against the invasive
Asian carp. The gar are later returned to the wild. (AP Photo/Rogelio V. Solis)
Still, the fish
has a public relations problem in some circles, including a boating group in
Illinois, whose members recently derided it as a "trash fish" and
questioned reintroduction efforts.
But avid angler
Olaf Nelson, who in 2013 was the first to catch an alligator gar in Illinois in
50 years—a 2-footer in a stocked lake—said they're important whether anyone
wants to fish for them or not.
"Whether
they're loved or hated, they're a natural part of the Illinois ecosystem,"
he said. "It's pretty rare that we can fix a mistake."
In this July 6, 2016 photo, U.S. Fish and Wildlife Service
fish biologist Dan Schwarz explains the process by which alligator gar eggs are
harvested, fertilized and being grown in special tanks on the grounds of the
Private John Allen National Fish Hatchery in Tupelo, Miss., in an effort to
reintroduce the once-reviled alligator gar as a weapon against another huge
species: invasive Asian carp. (AP Photo/Rogelio V. Solis)
In this July 6, 2016 photo, U.S. Fish and Wildlife Service
fish biologist Dan Schwarz pulls up a small alligator gar fish that the agency
is growing at the Private John Allen National Fish Hatchery in Tupelo, Miss.,
in an effort to reintroduce in various waterways and states as a weapon against
another huge species: invasive Asian carp. (AP Photo/Rogelio V. Solis)
This 1905 photo provided by The Field Museum shows staff
preparatory Richard Raddatz posing next to an alligator gar at the Field
Columbian Museum in Chicago. Biologists are restocking alligator gar to
waterways throughout the middle of the country, hoping the alligator gar - a
giant fish once driven to extinction in much of its historic range - can help
control invasive Asian carp. (Charles Carpenter/The Field Museum via AP)
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