SNAKEHEAD FISH TRAVEL OVER LAND?
I saw a recent article about invasions of tropical fish that are causing
environmental problems in canals in southern Florida. I have also heard
that a foreign fish called a snakehead, which has big teeth
and can travel over land, has been introduced into rivers in Alabama
and other southern states. If these reports are true, shouldnt
we be concerned?
Southern Florida is full of exotic animals and plants that have become
naturalized. Many small tropical fish have been released from home aquariums
by people who were moving from the area or simply got tired of having
an aquarium. Because of the warm climate and the absence of their natural
predators, many fishes from South America, Asia or Africa with similar
climates to Florida have survived and produced offspring. As with many
nonnative animals and plants that are introduced into a region, some
successfully compete with native species and can even replace them under
the group of fishes known as snakeheads, their ecological impacts are
still uncertain. According to the U.S. Geological Survey, the northern
snakehead is native to Russia, China and Korea. In the United States,
one was first reported in the wild in California, but they have not
become established on the West Coast.
this invasive species is now present in parts of Virginia and the Chesapeake
Bay area and a pond in New York, as well as in some river drainages
in Arkansas. Its occurrence in Alabama and other southern states has
not been documented. If you catch one, report it to your state wildlife
mouth of a snakehead can lead someone to think first that dental work
might be appropriate and second that being bitten would be a memorable
but highly negative experience.
to Pam Fuller, a USGS scientist who conducts research on snakeheads
and other nonnative fish species, they do have some nasty-looking teeth.
But she adds, its just a fish and does not have an
unusually impressive bite. Nonetheless, sticking your finger into the
mouth of any big fish with sharp teeth is not advised.
appearance, northern snakeheads look like bowfins (aka cypress bass
or mudfish), which occur naturally throughout much of the eastern United
States. However, northern snakeheads have a long anal fin (the one on
the belly in front of the tail) and a flattened head compared to the
small anal fin and bullet-shape head of a bowfin.
bowfins have a black spot on the tail. Northern snakeheads reach body
lengths of more than 2 feet. A related Asian species, the giant or bullseye
snakehead, is now found in southern Florida and can be almost 4 feet
long. The snakeheads found in Florida also have a spot on the tail like
eat a variety of zooplankton and small aquatic insects. Adults eat other
fish, sometimes one-third the length of their own bodies, as well as
crawfish and frogs. Snakeheads are different from most other fish, which
cannot survive for long out of water.
snakeheads have gills but can also gulp air and have been documented
to live out of water for up to four days. However, although a young
one may travel overland for several feet, a full-grown adult is too
large to move effectively, so your pet chihuahua will probably be safe
if it can make it to the pet door.
cause serious environmental problems where they become established?
The most likely impact will be because snakeheads not only eat other
fish but are also successful competitors with native fish that have
the same food base.
to control invasive species like snakeheads, pythons and fire ants are
often futile, and once established most such species are probably here
to stay. If you are an angler, the best approach with the northern snakehead
might be to find out what kind of bait they prefer.
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