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Invasive Species: Fish

Note: Invasive Carp

Invasive carp include bighead carp, black carp, grass carp and silver carp. Find out more about each of these species and about invasive carp in Michigan on each species’ profile below. 

Invasive Fish

Species that are not native and also have the potential to harm human health or to harm natural, agricultural or silvicultural resources can be listed as prohibited or restricted by the State of Michigan. If a species is prohibited or restricted, it is unlawful to possess, introduce, import, sell or offer that species for sale as a live organism, except under certain circumstances.


(Rhodeus sericeus)

Prohibited in Michigan

Bitterling are small (6-7 cm) fish with grey-green backs and silvery white sides and belly. They have a metallic streak on the hind ends of their sides. They live in marshes, lakes, ponds, muddy/sandy pools, and backwaters of rivers.

More information: Bitterling

Carp - Bighead

(Hypophthalmichthys nobilis)

Watch List - Prohibited in Michigan

Bighead carp have a large head with a toothless mouth and eyes that sit below the mouth. They can grow to 5 feet long and weigh up to 90 lbs. Bighead carp are able to establish populations in water bodies with a wide range of temperatures.  Spawning generally occurs following a flood event in large, turbulent rivers.

More information: Bighead carp

Carp - Black

(Mylopharyngodon piceus)

Watch List - Prohibited in Michigan

Black carp have a pointed head that is flattened at the front. Scales are blackish-brown darkening to bluish-gray at the edges, with an almost white belly.  They can grow to 6 feet long and weigh up to 150 lbs. Black carp inhabit large rivers and lakes but require large rivers for reproduction.

More information: Black carp

Carp - Grass

(Ctenopharyngodon idella)

Watch List - Prohibited in Michigan

Grass carp have large scales that appear crosshatched and eyes that sit even with the mouth. They can reach lengths of more than 5 feet and weigh more than 80 lbs. They prefer quiet, shallow waters.

More information: Grass carp

Carp - Silver

(Hypophthalmichthys molitrix)

Watch List - Prohibited in Michigan

Silver carp have a light silver body with a white belly and eyes that sit below the downturned, toothless mouth. They may exceed three feet in length and can weigh up to 60 lbs. These fish primarily inhabit large rivers.

More information: Silver carp

Eurasian Ruffe

(Gymnocephalus cernuus)

Prohibited in Michigan

Eurasian ruffe are about 25 mm in length and have olive-brown color on the back side and a yellow-white belly. They have fused dorsal fins with no notch and dark spots on the membranes between the rays of the fins. They have a small, downturned mouth.

More information: Eurasian ruffe


(Leuciscus idus)

Prohibited in Michigan

Ide are chunky-bodied fish with a distinctly arched belly and back and a small, bluntly pointed head. There are two colors - silver morphs have greyish-olive backs and silver-white sides and bellies with reddish pelvic and anal fins. Golden morphs have bright orange backs and silvery-orange sides and bellies with bright orange dorsal fins.

More information: Ide

Japanese/Oriental Weatherfish

(Misgurnus anguillicaudatus)

Restricted in Michigan

Oriental weatherfish have an eel-like body that is brown with greenish-grey marbled markings on the dorsal side and pale silver coloration on the ventral side. They have a small, narrow mouth with thick and fleshy lips and six barbels. They can reach 28 cm in length but averages are smaller. The female is often longer than the male.

More information: Japanese/Oriental weatherfish

Northern Snakehead

(Channa argus)

Watch List - Prohibited in Michigan

Northern snakeheads can reach up to 33 inches in length. They have a tan color with dark brown mottling, an extended anal fin, a pelvic fin up near the gills and pectoral fins. They have sharp teeth like a pike or pickerel.

More information: Northern snakehead

Round Goby

(Apollonia melanostomus)

Prohibited in Michigan

Round gobies can reach up to 30.5 cm. The young fish are solid slate-gray color. Older fish are blotched with black and brown. They have a black spot on the rear of the first dorsal fin and a fused pelvic fin. They are a freshwater fish and behavior includes perching on rocks in shallow areas of water. They may also flourish in open sandy areas.

More information: Round goby


(Scardinius erythrophthalmus)

Prohibited in Michigan

Rudd can reach 48 cm in length and have a deep stock body with a green-brown back, brassy yellow sides and near white belly. They have bright red-orange pectoral, pelvic, and anal fins. The tail fins are red-brown. They have a red spot on the iris of the eye. Rudd prefer stagnant and slow-flowing freshwater with a lot of vegetation.

More information: Rudd

Sea Lamprey

(Petromyzon marinus)

Sea lamprey have an eel-like body with two close dorsal fins, seven gill openings and a large round mouth with sharp, curved teeth and rasping tongue.

More information: Sea lamprey

Stone Moroko

(Pseudorasbora parva)

Prohibited in Michigan

Stone moroko are approximately eight cm long and have yellowish-green to silver body color. They have pale yellow fins and the dorsal fin have a darker stripe. Young ones have a dark stripe along the side. They prefer well vegetated ponds, small lakes, and small channels.

More information: Stone moroko


(Tinca tinca)

Prohibited in Michigan

Tench have thick-set bodies ranging from deep olive to pale golden tan and bright orange-red eyes. They have a small barbell at both corners of the mouth. Tench are freshwater members of the carp family that inhabit lakes with weedy or muddy bottoms. They are able to survive in low oxygen, degraded waters.

More information: Tench

Tubenose Goby

(Proterorhinus semilunaris)

Prohibited in Michigan

Tubenose gobies are small, reaching lengths of up to 11 cm. They are mottled brown in color with small scales and have conjoined pectoral fins and two dorsal fins. They have a tube-shaped protuberance extending from each anterior nostril. Unlike the round goby, they have lines and no spot on the first dorsal fins.

More information: Tubenose goby

Wels Catfish

(Silurus glanis)

Prohibited in Michigan

Wels catfish can grow up to 10 feet long and live up to 80 years. They have a very large mouth with three pairs of barbels, one pair on the upper jaw and two on the lower jaw. They have brown back and sides with a nearly white belly. They generally inhabit lowland rivers, backwaters, and well-vegetated lakes.

More information: Wels catfish


(Sander lucioperca)

Prohibited in Michigan

Zanders have a slender body with a grey-green back, white belly, and dark transverse rings. The average length is 50 cm. They have two dorsal fins, pointed head and many small teeth with a few large teeth. They are not a hybrid of a pike and perch, although they are also known as "European pike perch."

More information: Zander