Round Goby
The round goby is a small, soft-bodied fish with a distinctive black spot on its first dorsal fin. It has large, protruding eyes and its body ranges from 4-10″ in length. While juveniles are grey, adult round gobies have grey, black, brown and olive green markings.
Yellow Floating Heart
Yellow floating heart is an herbaceous perennial that has stout, branching stems. The heart-shaped, almost circular, leaves are usually oppositely arranged and frequently purplish underneath. Bright yellow flowers have 5 petals and distinctively fringed edges. It spreads both vegetatively and by seeds.
Variable-leaf Watermilfoil
Variable-leaf watermilfoil is a submerged perennial that looks like many native plants, including native watermilfoil species. It has 4-6 feathery leaves whorled around the stem, but some leaves can be alternate. Its leaves are divided into 7-14 pairs of leaflets, the dense leaf arrangement gives this plant a bottle brush appearance. Stems are thick and reddish-brown. In mid to late summer, blade-like, serrated leaves with small, reddish pink flowers form an erect spike that emerges from the water.
Quagga Mussel
The quagga mussel is a filter-feeding, freshwater, bivalve mollusk. It is pale toward the end of its hinge and about 3/4″ wide.
Asian Clam
Asian clam is a freshwater bivalve mollusk. The outside shells are yellow-green to brown with elevated concentric rings. If the color chips away, white spots can be seen underneath. The inside of the shells may be light purple. Adults are small, usually less than 1 1/2″ in length.
Fishhook Waterflea
Fishhook waterfleas are tiny crustaceans less than 1/2″ long with long, sharp, barbed tails. The fishhook waterfleas have a slender spine and prominent S-shaped loop on the tail. Fishhook waterfleas collect in gelatinous globs on fishing equipment and lines.
Spiny Waterflea
Spiny waterfleas are tiny crustaceans less than 1/2″ long with long, sharp, barbed tails. Spiny waterfleas collect in gelatinous globs on fishing equipment and lines.
European Frog-bit
European frog-bit is a free-floating, short-lived perennial. The leaves are leathery and round with undersides that may be dark purple. Flowers are white with yellow centers, and bloom in the summer.
Water Chestnut
Water chestnut is a fast-growing, floating annual that can grow to 16 ft. The most distinctive trait of this plant is its thorny nutlets.
Brittle Naiad
Brittle naiad is an herbaceous annual that grows in dense clusters. Its leaves have visible serrations and are long, pointed and oppositely arranged on highly branched stems. The plant can reproduce from stem fragments, or from small seeds which grow along its stem.
Brazilian Elodea
Brazilian elodea is a submerged perennial that looks similar to american waterweed (Elodea canadensis), a common native aquatic plant. Brazilian elodea has finely-toothed leaves that are bright green, bushy, and are usually arranged in whorls of four around the stem. The plant has round stems that can grow in water up to 20 ft. deep and often branches near the surface. It reproduces via plant fragmentation.
Hydrilla
Hydrilla is a submerged perennial that looks similar to american waterweed (Elodea canadensis), a common native aquatic plant.
Eurasian Watermilfoil
Eurasian watermilfoil is a submerged perennial that looks like many native aquatic plants, including native milfoil species.
Zebra Mussel
Zebra mussels are filter-feeding, freshwater, bivalve mollusks. Zebra mussels are small, ¼” to 1 ½” long, and D-shaped with light and dark brown stripes.
Curly-leaf Pondweed
Curly-leaf pondweed is a submerged perennial that resembles many native pondweeds. Care must be taken to correctly identify this species. Rigid, reddish-green, oblong leaves have distinct, finely-toothed, wavy edges. The plant’s flat, reddish-brown stem grows from 1-16 ft. Most reproduction is from winter buds, called turions.
