Rusty Crayfish (Orconectes rusticus)
Live crayfish are used classrooms for valuable learning, but please do not release them into wild!
During the school year, within schools in Oregon and the west, the rusty crayfish, native to the Ohio River basin, is a species used for teaching and learning in elementary schools as part of a nationally acclaimed curriculum on “The Structures of Life”. Living crayfish in the classroom make for excellent learning projects allowing students to understand and explore science, functions and behaviors through observation, research, questioning, reasoning, writing and discussions. On the other hand, these non-native Rusty crayfish are an aggressive and invasive species and releasing them into our local waterways will harm our native fish, plants and other native organisms in our waterways, let alone not wanting to wade in barefoot infested with invasive species such as the rusty crayfish . Teachers and students face a dilemma over what to do with rusty crayfish (for that matter any live organism used in a classroom) once the class science project is completed. Valuable learning can occur when teachers work with their students in discussing responsible options and consequences on what to do with organisms such as the rusty crayfish after the completion of a school project.
Species at a glance
The rusty crayfish is a large crayfish species that has emerged as an invasive threat to aquatic ecosystems in many regions of the country. This opportunistic feeder can exceed 4 inches long, has strong claws, and aggressively displaces native species such as our native American signal crayfish.
It is a voracious consumer of aquatic plants, fish eggs, and invertebrates (including aquatic insects, clams, mussels, worms, and snails).
Distribution
The rusty crayfish is native to the Ohio River basin, including parts of Ohio, Kentucky, Tennessee, Illinois, and Indiana. It has been introduced to new areas across much of the
Great Lakes Region, New England, and parts of New Mexico. Although several sightings have been reported, the rusty crayfish has not become established in the Pacific Northwest. We need your help to keep out of our waterways. So please keep an eye for them, encourage the learning from the curriculum and science project, but please do not release them.
Identification
Rusty crayfish are most easily identified by large, rust-colored spots on either side of the carapace (shell). They have large, reddish-brown to grayish-green claws with black
bands at the tips. The claws leave an oval gap when closed.
How this Species Spreads
Due to its hardy nature, rather attractive features and relatively large size, the rusty crayfish is often used in aquariums, particularly in classroom settings and sometimes as bait for fishing. Releasing aquarium species into new ecosystems provides another pathway for the rusty crayfish to spread.
Habitat
The rusty crayfish inhabits freshwater lakes, rivers, and streams with substrate of rock, gravel, clay or silt. They are found in deep pools and fast currents. They prefer areas that offer shelter from predators, such as rocks, logs, and debris.
What you can do
If you use or see these crayfish in the classrooms in our waterways, please contact the Extension office or call . We can help extend the learning from the classroom activities and help provide options on what to do with these organisms after the complete. If you suspect that you’ve come across a rusty crayfish in our local waters, report the sighting to the Oregon Invasive Species Hotline, 1-866-INVADER and contact the Extension Office.
A color publication titled “You Can Stop the Spread of Aquatic Invasive Species (AIS). 2006. 4pp. ORESU-G-06-003”can be obtained at the OSU Washington County Extension office or from. Oregon Sea Grant at OSU : http://seagrant.oregonstate.edu/sgpubs/onlinepubs/2007publications_catalog.html
Sam Chan
Watershed Health Educator/Aquatic Invasive Species Specialist
503-679-4828