Take note of where your crawfish are coming from: some imported crawfish have high levels of antibiotic residues and other substances that are banned from use in the United States. Play it safe and stick with Louisiana Crawfish.
Live crawfish can be found from November through July, but are most prevalent from April through June. Tail meat freezes well and can be found at retailers year-round.
Live crawfish are typically packaged in plastic mesh sacks at about 35 lbs. each. Crawfish in good health and held under good refrigerated conditions can be stored up to four to five days. Live crawfish should be kept in refrigerated coolers, either packed with ice or with the relative humidity replenished by daily wettings or with moisture-retaining blankets of wet burlap.
Crawfish tail meat that has been cooked and deveined can be frozen for several months. If the tail meat is to be frozen for more than five months, it’s best to wash the yellow fat off of the meat as it can become rancid after prolonged freezing. Package the tail meat in small 12 oz. or 1 lb. sealed containers and expel all air before sealing. Thaw in the refrigerator for a full day before cooking.
It’s best to use cooked tail meat within a day or two after peeling for best flavor. Freeze the meat if you don't plan on cooking until later.
Crawfish are classified by size: #1 equals 15 or fewer crawfish to a pound, #2 equals 16–20 crawfish per pound, and #3 equals 21 or more crawfish per pound. Figure on roughly four pounds of live crawfish per person. Ten pounds of whole crawfish yields 1 1/2 pounds of tail meat. Three to four pounds of crawfish (with shell) serves 1 adult, while 10 pounds of whole crawfish yields about 1.5 pounds of tail meat.