Crayfish in the Classroom
Crayfish Biology
By Trish Patrick

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The crayfish, also known as the crawdad or crawfish, is a crustacean in the class Crustacea of phylum Arthropoda of kingdom Animalia. The typical length is about 3", with the smallest full-grown crayfish being less than 1"; and the largest being about 16". The average life span is about 2 years. Crayfish live throughout the world in freshwater streams beneath sticks and stones or within caves. They are most active at night when feeding on snails, algae, detritus, insect larvae, minnows, and worms. Crayfish are eaten by fish, raccoons, turtles, birds, alligators, and humans.

Because of its very specialized, diverse yet similar appendages, the crayfish is the perfect specimen to convey to students the relationships between structure, function, and environment. You can easily demonstrate these relationships by allowing students to observe live crayfish through open inquiry. Then they can perform a hands-on, guided, follow-up dissection, which reiterates the specific functions of the crayfish's body parts and appendages.

• Crayfish appendages dissection handout (PDF)
  (Key) (Handout)
• Crayfish internal dissection handout (PDF)
  (Key) (Handout)
• Crayfish external dissection handout (PDF)
  (Key) (Handout)

• Live Crayfish
• Crayfish Food
• Freshwater Aquarium Kit

• Carolina's Perfect Solution® Crayfish
• Crayfish Dissection