Snakeheads fish

Northern snakeheads are a species of fish native to East Asia. Some species can stand upright and
wriggle for short distances across land. In Asia it is regarded as a good eating fish. In North
American no one thought much of the fish until it showed up in the Potomac River in Washington
D.C. along with reports that it viscously ate other fish and multiplied quickly and walk across land
and infest other waterways.
Helen Fields wrote in Smithsonian magazine: The voracious "Frankenfish" has turned up in the
Potomac River, Lake Michigan and a California lake, sparking fears of an ecological Armageddon.
But is the Asian import a monster or the victim of monster hype? The northern snakehead is native
to Asia and is one of 29 snakehead species. It made its national news debut in 2002, after an angler
at a pond behind a strip mall in Crofton, Maryland, caught a long, skinny fish, about 18 inches from
end to end, that neither he nor his fishing buddy recognized. [Source: Helen Fields, Smithsonian
magazine, February 2005]
It was after another angler caught a snakehead in the same pond and netted some babies that all
hell broke loose. National newspaper and TV news reports described snakeheads as vicious
predators that would eat every fish in a pond, then waddle across land to another body of water and
clean it out. A reporter from the Baltimore Sun called it “a companion for the Creature from the Black Lagoon." The scariest reports, fortunately, turned out to be mistaken. While some species of
snakeheads can indeed wriggle long distances across the ground, the northern snakehead---the
only species found in the Crofton pond---appears not to be one of them. But northern snakeheads do
like to eat other fish, and a heavy rain could conceivably wash one or more from the pond into a
nearby river that runs through a National Wildlife Refuge and into the Chesapeake Bay, the largest
estuary in North America. To eliminate the snakehead menace, Maryland wildlife officials dumped
the pesticide rotenone into the Crofton pond, killing all of its fish. Six adult snakeheads went belly up---as did more than 1,000 juveniles. Problem solved. Or so it appeared. Two years later, northern
snakeheads fulfilled biologists--- worst fear and showed up in the Potomac River.
Besides Crofton and the Potomac, the fish have popped up in several other places in the United
States. In 1997, one was caught in a Southern California lake. A couple more appeared in Florida
waters in 2000. In Massachusetts, one was caught in 2001 and a second in 2004. And in July 2004,
an angler caught two in a lake in a Philadelphia park. Like the Crofton fish, the Philadelphia ones
had settled in and started reproducing. But unlike the Crofton fish, they had access to a river---the
Schuylkill, which feeds into the Delaware.
The northern snakehead, which is native to parts of China, far eastern Russia and the Korean
peninsula, may seem plug-ugly to the undiscerning eye---it has big, pointy teeth and, given its
particularly heavy mucus covering, a slime problem. It can grow up to five feet long. Like its reptilian
namesake, it's long and slender and can sport blotchy snakelike patterns on its skin. Unlike most
fish, the northern snakehead has little sacs above its gills that function almost like lungs; the fish can
surface and suck air into the sacs, then draw oxygen from the stored air as it swims. The air sacs
are handy for surviving in waters that are low in oxygen, and even allow the fish to survive out of
water for a couple of days, as long as it doesn't dry out. A female lays thousands of eggs at a time,
and both parents guard their offspring in a large nest they make in a clearing of aquatic plants.
Northern snakeheads are a popular food in their native range; they're said to be good eating,
particularly in watercress soup, if a bit bony. They're fished commercially and raised in fish farms in Asia."But after they started showing up in American waterways “the U.S. Fish and Wildlife Service soon banned the importation and interstate transport of snakehead. But the bans haven't stopped
everyone. A Los Angeles grocer was arrested for allegedly smuggling live northern snakeheads into
the country from Korea and selling them in his store; he pleaded guilty to importing an injurious
species. U.S. fans of snakehead soup and other delicacies, however, may still legally obtain killed,
frozen snakeheads, which are available in many of the Asian markets that once sold them live.
Some fisherman are happy about the arrival of snakeheads and say their a great sporting fish and
are challenging and fun to catch.

A snakehead cousin---the bulleye from India and Pakistan---is established in a canal system in
Florida. In the mid 2000s it was still possible to import Asian swamp eel, another species that was
causing havoc in Florida. In the late 1960sm the walking catfish, another species, showed up in he
wild. Great alarm was raised about it but in the end it didn't cause major damage.
The red-eared slider turtle, a species native to the Mississippi basin, is found across Asia and
southern Europe. It was original shipped out of the United States as pet and food source, and is now
now consuming native frogs, mollusks and even birds in its adopted lands, and driving away native
turtles by out competing them.

Đăng nhận xét

0 Nhận xét