Crayfish are known by many nicknames, including mudbugs, yabbies, mudpuppies, crawfish and crawdads. Like crab, lobster, and prawn they are decapod (i.e. “ten-footed”) crustaceans with twenty body segments grouped into two main body parts, the cephalothorax and the abdomen. Many people associate crayfish with warm slow moving rivers, ponds and lakes, but they can also be found in cool, clear streams as shown in this photo of a Pacific Coast stream. Peeking below the surface we found a mass of crayfish wedged along the margin of a submerged log. Most crayfish are nocturnal, utilizing some form of shelter like a burrow, rock, or log to remain hidden during the day. Nocturnal organisms are essentially using a form of crypsis (the ability to avoid detection by other organisms) in order to elude predators. If you taste as good as a crayfish, it’s a good idea to remain concealed.
Photo source: FISHBIO