A Crayfish Called Rusty
There is one caveat to crayfish for dinner: The only legal crayfish to catch in Northern Michigan waters is known as the rusty. That isn’t as problematic as it sounds, however, because this large, edible invasive monster is so prolific chances are it will be what you catch—not one of our sweet little native crayfish that rusties have endangered. The Michigan Department of Natural Resources actually wants you to eat rusties.
Native to rivers and streams in Ohio, Indiana, and Kentucky, rusty crayfish started turning up in Northern waters 50 or so years ago (biologists aren’t sure exactly when) after nonresident anglers brought them here by the bait-bucketful. What fishermen didn’t use they simply tossed overboard at the end of the day. Now rusties are here for good. Easily distinguished from the native Great Lakes crayfish, which they vastly outnumber, an adult rusty can grow up to four inches long, not including the fearsomely large claws that are capable of pinky-pulverizing power. (Take my word on this.) But their most identifiable characteristics are the two distinct markings found just behind the head—on the sides of their carapace, to be exact—precisely the spot you would hold the crayfish when trying to avoid being pinched. The marks resemble splotchy stains, one on each side, as if left there by two celestial fingers dipped in rust-colored ink.
Rusties live in dense, shallow-water colonies with anywhere from four to 54 crayfish per square yard. With highly territorial dispositions and a locustlike ability to reproduce (a single female can lay anywhere from 85 to 575 eggs every year) there’s really not a river, stream, or boat harbor in Michigan where a person looking for a little culinary adventure can’t find rusty crayfish hiding under almost every rock.