Joe Prokupek, age 10, of Plattsmouth, Neb., for his question:
HOW CAN CRAWFISH SURVIVE A DROUGHT?
The crawfish, alias the crayfish, is a rather large land dwelling shrimp. He breathes through gills, and his body needs to be kept moist. He prefers to live underwater in a lazy stream but sometimes he finds himself in a soggy swamp. During a dry spell, he digs way down through the mud and hides himself in a moist underground burrow.
Nowadays, some people cultivate crayfishes in rice paddies. The growing rice plants like to stand knee deep in soggy soil, and from time to time the fields are flooded. This suits the crayfish just fine. When the fields are underwater, they swim around gobbling up scraps of food.
When the overflow drains away, they nestle down in the mud and continue eating scraps of debris.
As the neighborhood becomes drier, they burrow deep down in the dirt and rest until the water returns. In some cases, a crayfish may dig a burrow as deep as one, two or even three feet. As they dig, the dwindling water supply trickles down to the bottom of the burrow.
This is enough to keep him comfortably moist, at least for the moment. But the clever crayfish looks ahead and makes plans to protect himself from a possible drought. When his burrow is done, he piles a lot of dirt around the opening at the top. This seals in the moisture so his hideaway stays comfortable until the rains return.
Sometimes the pile of dirt on top of his burrow is four, five or six inches high. In some cases it is as high as 10 inches. In any case, you usually can find it if you search around in crayfish territory. Then you can fool him by poking down a stick. If he makes a grab for it, you can pull him out and have him for dinner. Many crayfish burrow out of sight during the dry season. But they are sure to reappear in the fall, for this is the mating season.
The female crawfish goes into a burrow to lay her 100 or so little round eggs.
Through the winter they are attached to her swimmerets. Come spring, they hatch into mini crawfish that use their glassy little claws to cling to the mother's body. They shed their crispy skins as they grow and each molting is a risky job that takes about six hours. Many of the youngsters fail to survive their early molts.