Mississippi's AMRAT 2004 Dirty Dozen “Most-Wanted” Non-native Animals

1.

Common name:

Rio Grande cichlid

Scientific name:

Cichlasoma cyanoguttatum

Description:

The Rio Grande cichlid is the only cichlid native to the US, normally found in southern Texas; very colorful with vertical banding and blue iridescent patches over its body; grows to 6 inches in length.

Means of introduction:

Released into Lake Pontchartrain from the aquarium trade in the early 1990s; accidentally introduced into Florida and other parts of Texas from fish farms.

Economic impact:

Very aggressive and competes with centrarchids (sunfish) for food and nesting space.

2.

Common name:

Tilapia

Scientific name:

Oreochromis sp. and Tilapia sp.

Description:

Several species of tilapia have been found in US waters. They are freshwater fish that are capable of surviving in low salinity, brackish waters. Some individuals begin reproducing at only 2 ½ inches in length. Males mouth brood the young increasing their survival rates.

Means of introduction:

Originally from Africa; accidentally introduced in southern states from aquaculture facilities.

Economic impact:

Very aggressive and competes with centrarchids (sunfish) for food and nesting space.

3.

Common name:

Common carp and grass carp

Scientific name:

Cyprinus caprio and Ctenopharyngodon idella

Description:

Silver fish with large scales, may reach over 3 feet in length

Means of introduction:

Deliberately stocked into rivers; also stocked into lakes to control vegetation growth

Economic impact:

Voracious feeding behaviors may destroy nursery habitat for native fish species, making hunting food difficult for game fish like bass.

4.

Common name:

Silver carp and bighead carp

Scientific name:

Hypophthalmichthys molitrix, and H. nobilis

Description:

Large silver fish with small scales, eyes set low on head

Means of introduction:

Accidental release into the wild from aquaculture facilities or deliberate release into reservoirs and ponds to control algae blooms

Economic impact:

May reduce food availability for larval native fishes

5.

Common name:

Zebra mussel

Scientific name:

Dreissena polymorpha

Description:

Bivalve with alternating dark and light bands; attaches to any hard substrate with byssal threads.

Means of introduction:

Entered the Great Lakes in ballast water of ships from Europe, has spread southward down the Mississippi River.

Economic impact:

Clogs water intake pipes; encrusts boat hulls and buoys.

6.

Common name:

Brown swimming crab

Scientific name:

Callinectes bocourti

Description:

Resembles the common blue crab (C. sapidus) in appearance but with chocolate-brown coloration

Means of introduction:

Presumed introduction through ballast waters

Economic impact:

Capable of living in degraded environments; may compete with the blue crab for habitat

7.

Common name:

Australian spotted jellyfish

Scientific name:

Phyllorhiza punctata

Description:

Large jellyfish, up to 20 inches bell diameter and 25 pounds in weight; white spots covering bell; lacking elongated stinging tentacles

Means of introduction:

Populations of this species have been established in Terrebonne Bay, LA for at least 10 years; large numbers that entered the Mississippi Sound in 2000 believed to have arrived via the Loop Current

Economic impact:

Filter-feeding jellies capable of clearing the water column of plankton in a short time period; larvae of commercially or recreationally important species may be consumed

8.

Common name:

Big pink jellyfish

Scientific name:

Drymonema dalmatinum

Description:

Large jellyfish up to 30 inches bell diameter; long stinging tentacles, up to 20 feet in length; oftentimes pink in color

Means of introduction:

Presumed arrival to the Mississippi Sound via the Loop Current in the fall of 2000

Economic impact:

Unknown; consumes other jellyfish, primarily the common moon jelly, Aurelia aurita; has a venomous sting similar to the local sea nettle

9.

Common name:

Malaysian prawn

Scientific name:

Macrobrachium rosenbergii

Description:

Freshwater prawn (shrimp) with second pair of walking legs elongated; bluish in color

Means of introduction:

Native to southeast Asia, released in several Gulf States from aquaculture facilities

Economic impact:

May out-compete native Macrobrachium species

10.

Common name:

Mussels

Scientific name:

Brachidontes domingensis, Mytilus edulis, Perna perna, P. viridis

Description:

Blue, green, or brown mussels,

Means of introduction:

Sea water piping systems or ballast waters in ships

Economic impact:

Encrust any exposed surface including buoys, boat hulls, or water intake pipes; may out-compete native mussel species

11.

Common name:

Asian clam

Scientific name:

Corbicula fluminea

Description:

Off-white, yellow, or brown clam

Means of introduction:

Believed to have been brought to the US as a food item by Chinese immigrants

Economic impact:

Clogs intake pipes of power plants and other industrial water systems; competes with native clam species

12.

Common name:

Pacu, Tambaquí and Pirapatinga

Scientific name:

Colossoma macropomum and Piaractus brachypomus

Description:

Deep-bodied fish; mouths with large molar-like teeth

Means of introduction:

Released through the aquarium trade in lakes, ponds, and rivers

Economic impact:

When preferred food not available, may compete with larvae of native fish species for plankton