Crawfish
Crawfish (Crayfish, Crawdads) have a long segmented tail with 4 or 5 pairs of walking legs, antenae and two large pincers, and look like mini lobsters. They can range in colour from green, yellow, pink and sometimes red.
Description and Habitat
Crayfish are approx 7 cm (around 3 inches) long and appear mostly in fresh water, although they have been known in the sea. They appear in southern states and other european countries as well as some parts of canada. There are manys species of this crustacean….too many to list but they all look similar no matter where you live.
They are either food, bait or pests. Generally they inhabit streams but they can occur on your turf, and sometimes this can be a major problem. This is because they love water and the water table is high enough to supply their needs.
Crawfish Damage
Photos by Art Deitrich, Allen, TX
Although they do not feed on plants very much they can damage your lawn by creating small tunnels and create great mounds of dirt on your sod. When the sod dries out the hills can become like cement and very hard to get rid of. This can damage your lawn mower and make your lawn an eyesore. These photos above were taken on April 20, 2004 by Art Dietrich of Allen, Texas. He hasn’t seen the worst yet as these guys are gonna be dropping more bombshells until end of May.
Diet
They appear in the evenings for food, burrowing up out of the ground. Young craws can appear in the day on cloudy days and this can make them easy to hand pick and dispose of. They feed on small animals dead or alive. Included in thier diet are insects, snails, slugs, algae, larvae, small fish and occasionally flora and fauna. Young craws may be found during the day if it is overcast. After a major rain, these little guys can plug up your drainage systems.
Llifecycle
In early spring female crawfish burrow after mating and lay 200-400 eggs. Males then deposit sperm as fish would. The female then coats the eggs so that they may stick to her tail. Eggs hatch within 2-3 weeks. The babies are carried for up to 10 days after hatching, and this is called the ‘berry’ stage. As they grow into adults they shed their shells often and can live up to 2 years. No problem here as this is a valuable organic ingredient to the soil.
How To Get Rid Of Crawfish
Natural predators of the Crayfish include alligators, burbots, turtles, squirrels, storks, grackles and other predatory birds. I do not recommend controls since crawfish are beneficial, however if you have a major problem you can try one of these.
- Hand pick in the day or early evening
- Crawfish traps baited with fish, chicken or other meat
- Corn Gluten Meal (can be purchased at organic nurseries)
- Tile and drain the areas where they appear
- Poke a sharp stick in the hole and hope you squash them
- High nitrogen organic fertilizer (blood and bone meal are both high in nitrogen)
- Eat them