Invasive Species of Virginia

Invasive
Species

of
Virginia

By: Jack Meadows
Block: 3

Rusty Crayfish

Rusty Crayfish/ Orconectes rusticus
Information:

● The rusty crayfish (Orconectes rusticus) is a large, aggressive species of freshwater crayfish which is native
to the United States.
○ Adult rusty crayfish can reach lengths of over 10 centimeters (4 inches), although they reach maturity at
about 4.4 cm (1.7 in),[5] and can range in color from greenish grey, to reddish brown.

● Its native region is the Ohio River basin, spanning tributaries in Western Ohio, Indiana, Kentucky, and
Northern Tennessee; cryptogenic in Lake Erie.
○ Rusty Crayfish was first seen in the Great Lakes near the mouth of the Maumee River, Ohio in the early
1800s.

● The rusty crayfish is actually native to the southern United States. It is believed that they were probably
introduced to new areas by fisherman using them as bait.

● They compete with the Crayfish indigenous to other regions, destroy aquatic plants and may reduce
populations of fish and invertebrates.

● Rusty Crayfish live in lakes, ponds and streams, preferring areas with rocks, logs, and other debris.

Chinese Mitten Crab

Chinese Mitten Crab/Eriocheir sinensis
Information:

● The Chinese Mitten Crab is a medium-sized burrowing crab that is named for its furry claws, which resemble
mittens.
○ distinguishing features are the dense patches of dark setae on its claws.
○ The Chinese Mitten crab's body is the size of a human palm.
○ The carapace is 3–10 centimetres (1.2–3.9 in) wide, and the legs are about twice as long as the carapace
is wide.

● As its common name suggests, the Chinese mitten crab is native to the pacific coast of China and Korea.

● It is believed Chinese mitten crab were introduced to the US intentionally to create a fishery and provide a
food resource.

● They may out‐compete native crab,mussels, and crayfish for food and space.The mitten crab can even be a
threat to human health – as they are an intermediate host of the Oriental lung fluke.

● The Chinese mitten crab’s habitat are in rivers, estuaries and other coastal habitats of eastern Asia from Korea
in the north to the Fujian province of China in the south. It has also been introduced to Europe and North
America where it is considered an invasive species.

Northern Snakehead Fish

Northern Snakehead Fish/Channa argus
Information:

● The Northern Snakehead Fish is A long, thin fish with a single dorsal fin running the length of the fish.
Overall color is brown with dark blotches.
○ a long dorsal fin with 49–50 rays
■ anal fin with 31–32 rays and a small, anteriorly depressed head
○ The Northern Snakehead Fish has a Maximum body size that exceeds 85 cm (33 inches).

● The Northern Snakehead Fish is from China, Russia and Korea, but more specifically, the northern snakehead

is found in the lower Amur River basin.

● The Northern Snakehead Fish first showed up in the silverwood lake, in California back in 1997.
● The Northern Snakehead Fish is considered harmless. It is known as a aggressive species though and competes

with all the other fish in the water.
● Their habitat is in stagnant water with mud substrate and aquatic vegetation, or slow, muddy streams; it is

primarily piscivorous, but is known to eat crustaceans, other invertebrates, and amphibians.

Zebra Mussel

Zebra Mussel/Dreissena polymorpha
Information:

● The Zebra mussel is a small freshwater mussel.
○ a striped pattern commonly seen on their shells, though it is not universally present.
■ Usually about the size of a fingernail
● Can grow to a maximum length of nearly 2 in.
○ Shells are D-shaped, and attached to the substrate with strong byssal threads

● The zebra mussels are native to Eastern Europe and western Russia.
● The Zebra mussels were introduced in 1985 to the Great Lakes region. Released by ocean-going ships in

infested ballast water.
● They can be harmful to cities and power plants when they clog the water intakes. Zebra mussels have caused

drastic declines in native clam and mussel populations in some locations. Zebra mussels compete with other
invertebrates and young fish for plankton, the primary food source for these groups.

Imported Fire ant

●

Imported Fire ant/ Solenopsis invicta
Information:

● The Imported Fire ant is a small ant with workers varying from 1/8 to 1/ 4 inch long. It is usually dark reddish
brown in color and has two nodes on the petiole and a two-segmented antennal club. They are similar in
appearance to many of our common house and field ants.

● The Imported fire ant is native from South America.
● The ants were introduced in Mobile, Alabama, about 1940. The way they were introduced is unknown.
● The Imported fire ant can be harmful by stinging the humans or whatever disturbed them, it takes about 10 to

20 seconds for the ants to begin stinging after they climbed on whatever disturbed them. They compete with
other native ants for food.
● Their habitat is large ant hills all around the united states.