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The Difference Between Lobsters & Crayfish

Crayfish and lobsters are cherished by food lovers worldwide for their sweet, delicate flesh. For culinary purposes the two are interchangeable, with most of the meat found in the large claws and the tail. There are few differences between lobsters and crayfish, and the exact relationship between the two is the subject of hot debate in the academic world. For the average person, however, the distinctions are minimal.

Habitat
- The most obvious distinction is that lobsters live in saltwater, while crayfish or crawfish as they're known in Louisiana live in fresh water. True (clawed) lobsters are only found in the North Atlantic, with closely related species living in Europe and the eastern coast of North America. Clawless lobsters, referred to as rock or spiny lobsters, live in warm or cool climates in the rest of the world's oceans. Crayfish are found in freshwater in most temperate and tropical regions. Confusingly, rock lobsters have been traditionally known as "crayfish" in some regions.
Size
- Lobsters generally are larger than crayfish, although the largest crayfish can weigh more than 10 lbs. In most areas the smallest legal lobsters are one pound, so anything under that size will be a crayfish. Naturalist T.H. Huxley noted in a seminal 1880 study that English crayfish, for example, averaged no more than three inches in length, and that the largest specimen he'd found was only four inches.
General Description
- Lobsters and crayfish are described by scientists as "decapods," meaning they have five pairs of legs. Both crayfish and true lobsters have large claws, used for self-defense and feeding purposes. Both have segmented tails containing most of their flesh, with fan-like tail fins. They are predators and scavengers, eating anything from carrion to their own discarded shells after molting. Closely related clawed crustaceans include langoustines and Dublin Bay prawns, two commercially significant European species occupying a hazy middle ground between shrimp and lobsters.
Commercial Sources
- True lobsters are commercially harvested on both sides of the North Atlantic, with Maine and Atlantic Canada accounting for the majority of the North American catch. Most are sold live and whole, though some are canned or frozen. Spiny lobsters are harvested commercially in the Caribbean, Brazil, Australia, New Zealand and South Africa, and are generally sold as frozen tails. Most commercial crayfish harvesting takes place in Louisiana and Australia, though there are numerous other fisheries around the world that are locally significant.

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