I typically place 400 crawfish into my 8 acre pond each spring - apparently crawfish either do well and flourish or don't take at all to a pond. It's an all or none scenario. In my case I was lucky and they survived and multiplied so I have a good crop of them - I caught a two pound bass last week and his craw (sorry for the pun) was full of a large crawfish. I get mine from a nearby wholesale bait shop - some larger grocery stores have them at times and you can purchase them their. Biggest problem I have had with them is keeping the birds and racoons from harvesting them. I just place them along the muddiest part of the pond when I release them. If established they are a great addition to the forage base.