Help With Breeding Crayfish

Crayfish -- also called freshwater lobsters, crawfish and crawdads -- are a type of crustacean that live in fast-running bodies of water. More than 150 species of crayfish live in North America, and about 550 species can be found around the world. Several types of crayfish make good pets and can live in home tanks. These creatures breed readily when treated well, but do require some special care to reach adulthood.

  1. Timing

    • In the wild, crayfish mate in autumn or spring, depending on the species. They lay eggs in late spring. The mother cares for the eggs and young for about two months in spring or summer, after which they become independent. In captivity, crayfish decide on a breeding season based on water temperature and light levels. In bright, warm environments, they may suddenly breed out of season. Tropical crayfish also breed more readily, since their natural environments provides more stable temperatures and lighting.

    Mating

    • During mating, the male crayfish climbs under the female. They may lie on their sides on the bottom of the tank. Crayfish fertilize their eggs outside their bodies. The male crayfish excretes a sperm packet, placing it on the underside of the female. This packet looks like a small ball of cotton. The female then curls up her tail, laying eggs and passing them through the packet of sperm. The female then attaches the eggs to her swimmerettes, on the underside of the tail. She moves the eggs around periodically to keep them aerated.

    Hatching

    • After three to four weeks (cold water species may take longer), the baby crayfish hatch from their eggs and immediately cling to the underside of their mother's tail. These tiny arthropods measure only about 1/16 inch long and look like tiny adults. Feed them fine-grained fish food; larger pellets may be too big for the baby crayfish to consume. Young crayfish remain under the tail until their first or second molt, two to three weeks after they hatch. Not all babies survive to adulthood. The other crayfish may eat some of their siblings, particularly in crowded tanks. Provide plenty of cover to encourage the survival of most of the litter.

    Considerations

    • While crayfish are either male or female, sexing some individuals can be difficult. Individual crayfish may display both male and female genital openings. The female opening appears in the middle of the animal, between the second pair of legs, while the male genital openings appear just under the tail, between the rear pair of legs. According to Crayfishworld, most of these "intersexed" crayfish are genetically male. Examine your breeding crayfish carefully to ensure accurate sexing.