Crayfish
Rusty Crayfish
Faxonius rusticus
These illustrations are AI-generated, not photographs, and are not to scale. They show what to look for; they are not a substitute for an expert identification.
How to identify it
Size: About 3 to 4 inches long.
- A rusty-red spot on each side of the shell, about where you would hold it between thumb and finger.
- Large, smooth claws with black bands near orange-red tips.
- A gray-green to reddish-brown body.
Don’t confuse it with
The native virile crayfish has no rusty side spots and often has bluish claws with pale bumps.
In Indiana it is native only to streams of the Ohio River basin in the south of the state. Elsewhere, including the northern lakes where it has been recorded, it is not native.
Where it came from
Native to the Ohio River basin, including parts of Ohio, Kentucky, Indiana and Tennessee.
Spread mainly by people, especially when leftover crayfish used as bait are dumped into lakes.
Earliest dated Indiana record: 1985, Lake Wawasee, Kosciusko County. This is the oldest dated record in the USGS non-native species database, not necessarily when it first arrived.
Why it matters
It is aggressive, eats large amounts of aquatic plants, snails and fish eggs, and pushes out native crayfish.
Indiana law
Not listed in Indiana's invasive species rules. The steps below still help keep it from spreading. Indiana DNR lists it among the aquatic invasive species it asks people not to spread.
If you find it
- Don’t move it. Before leaving the water, remove all plants, mud and debris and drain all water from your boat, motor, live well, bilge and trailer. Carrying plants listed in Indiana’s Aquatic Plant Rule on vehicles, boats or trailers is illegal and can bring fines. Clean boater tips
- Never release bait or pets. Don’t dump bait, aquarium animals or water-garden plants into any lake or stream. Put unused bait in the trash.
- Report it. Take a photo, note where you saw it, and report it through EDDMapS or the GLEDN phone app, or contact Indiana DNR’s aquatic invasive species program at 317-234-3883 or ais@dnr.IN.gov. Experts there can confirm what you found.
- Ask before removing or treating. On public lakes, any control of aquatic plants — chemical, mechanical, physical or biological — needs an Indiana DNR aquatic vegetation control permit. When a permit is needed
Indiana lakes where it has been recorded
1 Indiana lake on this site has a record of this species.
Kosciusko
A lake that is not listed may still have it. Records exist only where someone found the species and reported it, so “not recorded” does not mean “not present.”
Lake records: Midwest Glacial Lakes Partnership Conservation Planner; underlying records from the USGS Nonindigenous Aquatic Species database.
Sources
Earliest dated record: USGS Nonindigenous Aquatic Species database.