Rusty Crayfish

Rusty Crayfish (Above), Note the rusty patch on its side and the rusty patches along the tail.

Rusty Crayfish

(Orconectes rusticus)


These invasive species look very similar to native crayfish however there are noticeable “Rusty” looking patches on the sides of the shell, there are also black bands near the tips of each claw.  This species is extremely competitive with our native crayfish and competes with them for all resources. Commonly found in lakes, streams and rivers hiding under rocks and logs. They also eat many small invertebrates which fish din eon, this decreases food sources for many of our fish species


Originally they are from more southern regions in the US but they have now taken over in rivers such as the Ottawa, Kawartha lakes basin, Manitoulin island and some areas of northwestern Ontario.

Impacts & Control

There is not much that can be done to control them but there are bans on transporting them via land. Some actually consider these a delicacy and if you buy a trap and head down to a local stream with some bait you can catch them and eat them! Just be sure to identify native crayfish and release them! If you are a boater, then be sure to clean drain and dry your boat to ensure that no invaders are tagging along for a ride. You can also use reporting services if you suspect rusty crawfish in a water source.

Native Northern Clearwater Crayfish

Lookalikes–  There are many species of native crayfish in Ontario but the rusty crayfish has distinct rusty patches on its sides and tail. See the images to the right for examples of a rusty crayfish and a native crayfish.

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