Rusty Crayfish

Rusty Crayfish Distribution Map

Description

• Orconectes rusticus
• Spreads via bait buckets, ballast water, and aquarium dumping
• Females can carry fertilized eggs, one female can start a new population
• Native crayfish populations have been eliminated by the rusty crayfish through competition and disease
• Common aquarium crayfish

Rusty Crayfish

General Characteristics

• Larger, black-tipped claws
• Rusty spots on carapace
• Adults 2-8" long

Links

US Geological Survey (USGS)—Rusty Crayfish

Spiny Waterflea

Description

Spiny Waterflea Distribution Map

• Bythotrephes cederstroemi
• Small crustacean with a long, barbed tail spine
• Native to Europe
• Introduced into the Great Lakes in 1980’s via ballast water
• Spreads by overland transport of resting eggs on fishing gear, in bilge water, livewells and bait buckets
• Competes with juvenile fish for food

General Characteristics

• 3/8" long
• translucent color
• bulbous egg pouch
• straight caudal appendage
• look like gelatinous-like blobs on downrigger cables