Invertebrates 101

Chapter 7

Crustaceans - The Crayfish

Delicious by any name, Crayfish, Crawfish, Crawdads, or (my favorite) Mudbugs are freshwater relatives of the Lobsters they resemble, naturally occurring all over the world and farmed extensively for the table. The greatest number of species, well over 300, is found in the Southeastern United States. Crayfish prefer lowland areas where the water is abundant in calcium and well-aerated.

By White Knight (Picure taken by poster) [GFDLor CC-BY-SA-3.0], via Wikimedia Commons

Crayfish are a favorite food of many other animals and usually keep themselves concealed under logs and rocks. Most active at night, they feed on just about anything they can get their pincers on, from snails and algae to insects and tadpoles, including scavenging on dead fish and drowned earthworms. Adult Crayfish become most active at dusk, feeding until dawn, though young mudbugs (under a year old) may venture out during the day. When attacked they swim backwards with their powerful tails to escape danger.

As cute and cuddly (and delicious) as they may be, Crayfish are considered relatively destructive, mainly because they will try to consume pretty much anything in your pond. If they can catch it, they will eat it. Other than that tiny detail, these interesting little critters are typically not responsible for doing any other damage to a backyard pond.

If you’re interested in keeping Crayfish in an ornamental pond, you should be prepared to lose an occasional small fish from time to time, as well as the odd frog, tadpole or snails. Crayfish will do well in a quiet, calm pond but they actually prefer the high levels of dissolved oxygen in the moving waters of a stream. To avoid the downside of keeping Crayfish in captivity, feed your mudbugs a piece of fish or shrimp daily to keep their appetites in check. Larger fish are usually beyond their grasp, but there are a few verified instances where crayfish have been seen hanging onto a larger fish with one pincher, taking an occasional chunk out of the fish with the other, even as the fish is swimming around the pond. These minor wounds may lead to infection and the eventual death of the fish, at which point the Crayfish will finish its meal.