In the summer, after roughly the middle of May, the mullet thin out and many tarpon fishermen switch to crabs. A 100-pound tarpon will eagerly slurp down a small crab the size of a silver dollar, so don't let a bait-and-tackle shop try to sell you crabs the size of Frisbees — you don't need them, and they won't work as well. Mullet can be cast-netted, or you can sometimes buy them from a bait truck at marinas, but that's not always reliable. You're much more likely to find crabs on a consistent basis, and they work great. You will also pick up an occasional permit when using crabs for bait, a decidedly wonderful bonus.