Carp (Hypophthalmichthys nobilis)
Silver Carp (Hypophthalmichthys molitrix)
several species of carp have been introduced to North America, two species
of Asian carp that have become established in the Mississippi drainage,
the bighead carp and silver carp, pose a significant threat to the Great
Lakes because of their size, and ability to consume large amounts of food.
Asian carp can grow to 100 pounds and more than four feet in length.
Their native range is southern and central Asia.
There are reports of Asian carp “piling up” in large numbers
below dams, and filling the nets of commercial fishing boats to the point
that the nets cannot be lifted. The silver carp is currently spreading
rapidly throughout the larger rivers of the Mississippi River basin, with
dense populations and significant natural reproduction documented in slow
moving portions of rivers, within a wide range of temperatures.
Both fish species are deep-bodied and somewhat laterally compressed. The
bighead carp has a large head and very tiny scales, with eyes situated
below the midline
of the body. The gill rakers of a bighead are long, comb-like, and close-set. The silver
carp has gill rakers that are fused into sponge-like porous plates.
Initially imported to the southern United States to control plankton in
nutrient-rich catfish ponds, Asian carp first escaped to the wild due
to flooding in the Mississippi Basin in the early 1980s. These species
have now been recorded in at least 18 states, and are poised to enter
the Great Lakes via the Chicago Sanitary Canal. Great effort by Federal
and State agencies has taken place to build an electrical barrier downstream
of the canal to prevent their entry into the Great Lakes.
2010 Silver Carp Distribution
2010 Bighead Carp Distribution
Because bighead and silver carp prey on plankton and attain a large size,
these fish have the potential to significantly deplete plankton, a food
for some native mussels, larval fishes, and some adult fish. This competition
could reduce numbers of native species, which could dramatically change
aquatic communities. Asian carp have the ability to jump 6 to 10 feet
out of the water when excited by the wake of fast moving boats. Just recently,
a woman operating a personal watercraft in the Illinois River nearly drowned
after being knocked unconscious by a jumping Asian carp.
Use of juveniles as bait and the release of adults into new habitats contribute
to their spread. Early detection and control of isolated populations may
help to slow or restrict the spread of these Asian carp. You can do the
following to prevent the spread of the bighead and silver carp:
to identify the bighead and silver carp
of bait properly; do not release bait into the water
drain water from your boat, livewell,
and bilge before leaving any water access
dip your bait bucket into a lake or river if it contains water from
another water source
dump live fish from one body of water into another body of water
- An electric
dispersal barrier near Chicago, originally intended to prevent round
gobies from moving into the Mississippi River drainage, is now being
used to prevent Asian carp from getting into the Great Lakes.
To read more, view the Pennsylvania Sea Grant Asian carp fact sheet.
FOR MORE INFORMATION ON ASIAN CARP