Crayfish (or Crawfish) have become the species of the day for many folks in Washington. Washington Department of Fish and Wildlife manages recreational and commercial fisheries for crayfish. Be sure and consult the current Sport Fishing Rules Pamphlet to make sure you understand all rules.
Crayfish are prized culinary treats in Europe, particularly France and Sweden. They also enjoy some popularity in this country. Demand is high enough to support a number of "crayfish farms" in Louisiana, where large numbers are raised as annual crops in specially constructed ponds. Most of these are consumed domestically, but some are exported. Our West Coast species is generally larger than the Louisiana and European crayfish and according to some connoisseurs, is even tastier, but it has never been commercially cultured. Wild stocks have been harvested for many years from the rivers of Oregon and to a lesser extent, from the lakes of Washington.
Let's Get Names Straight. What is the Correct Name?
Crayfish. Crawfish. Crawdad. Even crawdab. Take your pick. These common names are equally acceptable and do not refer to different species, although there are in fact hundreds, but rather reflect regional differences in the speakers. The term "crayfish" probably arose from misunderstanding of an old word crevis, which is related to the German Krebs, or "crab." English speakers apparently heard the last syllable as "fish" and went from there. The scientific name for the species we have in Washington is Pacifastacus leniusculus, sometimes called the signal crayfish. Except where otherwise noted, when "crayfish" is used in this pamphlet it means P. leniusculus. Keep in mind, however, that the crayfish in other parts of the country or world are probably not the same species and may have quite different habits. For instance, what is true of the Louisiana commercial species Procambarus clarkii may not be true of our native crayfish.
What Kind of Animal Is the Crayfish?
Its just about what it seems—a small freshwater version of the lobster. Technically it is a decapod crustacean, related to lobsters, shrimps and crabs. P. leniusculus is large as crayfish go, reaching the minimum legal size of 3 ¼ inches in about three years, but often growing to 6 inches or more in 5 or 6 years. Crayfish prefer fresh animal food if they can get it, but they also eat a variety of aquatic plants. People think of them as scavengers because they are not very good at chasing down live prey. In fact, crayfish seem to prefer fresh food to decaying matter. Their diet may change considerably as they pass from the juvenile to the adult stage. This may help explain why juveniles rarely enter traps. Crayfish themselves serve as meals not only to humans but to a number of birds, fish and mammals as well.
P. leniusculus mates in the fall, and the females extrude from 100 to 300 eggs shortly thereafter. The eggs or "berries" remain attached to the underside of the female through the winter and hatch in late spring. The young crayfish remain as passengers on the mother for several weeks, molting twice before finally venturing out permanently on their own. In summer, a typical crayfish lake will contain immature males and females from the previous year which have not yet mated, adult males, adult females which have recently shed their young, and many newly-hatched juveniles. A few of the earliest born juveniles may grow enough to mate the same fall, but the majority are not able to reproduce until the following fall, when they are 17 or 18 months old. At this age, they are generally still below the minimum legal size. Females may spawn twice or more in a lifetime.
Our native species is considerably larger at full size than the species grown commercially in Louisiana, but does not grow nearly as fast. Louisiana crayfish farmers have a marketable crop within one year. Our species normally requires at least three years to grow to the minimum 3 ¼ inch legal size for harvest, by which time most have had a chance to reproduce.
Different age groups prefer different habitat—the juveniles favoring shallow, weedy areas where they can find protection from predators (and each other, since they are cannibalistic), and the large adults favoring deeper areas, perhaps to avoid birds and land mammals.
It is important you can distinguish the difference between our ONE native crayfish and nonnative species that have invaded our waters. Our native crayfish (Pacifastacus leniusculus) has a uniform brown coloration, white or light coloration at the claw joint, and a smooth surface on the claws and carapace (head and back) compared to the nonnatives. The nonnatives have pronounced bumps on their claws. If you cannot tell the difference, apply the native crayfish regulations to your catch. Our native crayfish may be threatened by nonnative crayfish, it is important not to take any actions that may endanger the status of our native crayfish.
For more information on native vs. nonnative identification see:
Fishing for Crayfish
When: Fishing is prohibited during the winter months to protect the population's reproductive capacity. Females normally carry eggs from late fall to the spring. Check the Fishing Regulation Pamphlet for current season dates.
Where: All waters of the state. Crayfish are found in lakes, streams and rivers.
Gear: One star trap, one ring net or one pot is considered one unit of gear. Up to five units of gear/person may be used to collect crayfish. General crab and shrimp gear rules (see the current Sport Fishing Regulation Pamphlet) apply. Unlike crab and shrimp, crayfish pots have no mesh size or buoy color requirements. Many crayfish pot designs can be found online, and sporting good stores usually carry them. Some people just use a standard minnow trap with an enlarged opening. There are lots of options out there – just be sure you follow WDFW regulations.
How: The best time to catch crayfish is at night. Fresh fish parts make good bait, but even dog food will work. Crayfish usually are found in areas where they can seek cover. Rock piles, boulders, weedy spots may all harbor crayfish.