Gone Crayfishin'

by Joan Banks
photography by Cliff White

Question: What kind of a bed does a crayfish use?
Answer: A stream bed.

Missouri has at least 32 kinds of crayfish, and most of them like the waters of Ozark streams. Turn over some rocks in one of these streams, and chances are you'll uncover one of these little crustaceans. But you'll have to look carefully. They blend into their environment and are hard to see. When startled, a crayfish will shoot off in reverse by flipping its tail.

Not all Missouri crayfish live in running water. Some live in ponds. Some burrow down from dry land to underground water.

One day in the marshy area beside my pond, I find a tiny crayfish castle. It's about 2 inches tall and is made of little blobs of mud. A hole plunges down through its center.

I weight a string with a nut (not the kind you eat, but one of those metal ones with a hole in the center). Then I tie a piece of bacon to the end of the string and lower it down the hole. I am going fishing-crayfishing.

Soon I feel a tiny tug on the string, and I pull it up. I have caught a crayfish. Or maybe it has caught me. After all, it has me on one end of the string. The crayfish is holding the other end with one of its pincers. (The word is pronounced PIN-sirz, but they still pinch.) The crayfish uses these pincers for digging, for defending itself and for catching its dinner.

Crayfish are called opportunists, which means they will eat what is available. They tidy up their environments by chowing down on decaying plant and animal matter. They also eat tadpoles, fish eggs, worms, insects and even other crayfish. Luckily, I am too big for its "catch of the day."

Crayfish are food for fish, raccoons, bears, otters, turtles, snakes, frogs, birds, and other animals, including humans. Eating and being eaten is all in a life's work when you're in the middle of the food chain.

I grab the crayfish carefully by its back, behind the claws. I don't want those large pincers to reach me! The crayfish looks like its relative, the lobster, only smaller. Both have crusty outer shells that protect them like suits of armor.

Of course, there's not much growing room in a suit of armor, so several times a year, the crayfish sheds its exoskeleton. This is called molting. For a day or two after it molts, the crayfish is soft and is easy prey for its enemies until the shell hardens.

"Crayfish breathe through gills like fish," says Bob DiStefanno, a fisheries research biologist with the Conservation Department. "The one difference is that they can breathe as long as their gills remain wet. That means they can get out of the water onto wet grass and survive."

But you probably won't see them in the daytime. Crayfish are nocturnal, which means they are mainly active at night, unless you disturb one in its hiding place.

A crayfish has three main body parts: a head, a thorax and an abdomen. It walks on four pair of legs and swims by moving its tail and little leglike swimmerets under its abdomen.

A female crayfish attaches her eggs to these swimmerets. She carries the eggs around with her. After they hatch, the baby crayfish cling to their mother for several weeks.

Some kinds of crayfish live two or three years. Others live longer. Some cave crayfish have lived up to 20 years, DiStefano says. One reason is they have few predators. Like other cave dwellers, cave crayfish are blind.

I release the little armor-suited crayfish on top of its castle wall so it can get back home in the water.

"If you pick up a crayfish, put it back where you found it," says DiStefano. A crayfish put in a new environment can wipe out other species.

Crayfish go by other names. Some people call them crawfish. I grew up calling them crawdads. But whatever you call them, they're fun to find-unless you find one attached to the end of your toe. Ouch!

No Hitchhikers!

Missouri's aggressive woodland crayfish showed up in a new habitat and put crayfish that lived there on the endangered list. How could a crayfish species move from its own habitat to another? Choose one.

a. In a bait bucket
b. On a boat trailer
c. In a collecting jar
d. Any of the above

Answer: d. Any of the above.

Species can move from one habitat to another in many different ways. Make sure you aren't the one to give them a lift.