ASIAN CARP

Bighead Carp (Hypophthalmichthys nobilis)
Silver Carp (Hypophthalmichthys molitrix)

Although 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!

ORIGIN
Their native range is southern and central Asia.

HABITAT
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.

IDENTIFICATION
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.

Silver Carp

Bighead Carp

SPREAD
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.

2003 Silver Carp Distribution

2003 Bighead Carp Distribution

IMPACTS
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.

PREVENTION AND CONTROL
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:

• Learn to identify the bighead and silver carp
• Dispose of bait properly; do not release bait into the water
• Always drain water from your boat, livewell, and bilge before leaving any water access
• Never dip your bait bucket into a lake or river if it contains water from another water source
• Never dump live fish from one body of water into another body of water
• Report new sightings - note exact location; freeze specimen in a sealed plastic bag and call Pennsylvania Sea Grant, Penn State Behrend (814-898-6420), or the Pennsylvania Fish and Boat Commission, Lake Erie Research Unit (814-474-1515).
• 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.

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