There are a whole lot of different species of crayfish, which to the untrained eye look all together too similar, with incredibly different behaviours, preferences, and suitability for pond stocking.

The primo crawdad for pond use is probably the Papershell Crayfish.

The worst is probably the Rusty Crayfish - they destroy other crawdads, will eat all the plants out of a pond (thereby depriving small fish of habitat), and actually can get you fined in some places for introducing an invasive species (6 figure fine for introducing Rusty Crayfish in Colorado last year!).

Here are some threads with crawdad info that you can peruse for much more detail:

crawfish

Brettski's Papershells

Crawfish? - taste and survivability

GW's Crawdad thread

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
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