Seeing Isn't Catching
If you've spent much time around tarpon, you know that seeing them doesn't equate to catching them. Their feeding impulse can turn on or off in an instant, and they can roll on the surface all around the boat for hours without ever striking a bait or lure, driving tarpon neophytes crazy. But becoming a successful tarpon fisherman is all about determining where and when that feed switch will turn on.
Tarpon migrate into the Florida Keys each spring, from the Gulf of Mexico primarily, but the fish move back and forth between the bay and the ocean at will, and in June you can find tarpon along both the Atlantic and Gulf coasts of Florida in a great many places. But if you study a map, you'll quickly learn why the passes of the Keys (often interchangeably referred to by the names of the bridges spanning them) are such special places. They are the only ingress and egress points between these two bodies of water for hundreds of miles. If tarpon want to move from the Gulf to the Atlantic and don't swim around the Keys west of Key West, they are swimming under one Keys bridge or another at some point.
The key to catching them, therefore, is to be at the right pass at the right time. Most savvy tarpon captains choose to anchor in the passes and fish live baits under floats. Anchor lines are rigged with floats and quick-release loops so the boat can be released quickly from the anchor and the tarpon can be chased down immediately after hook-up.
But you needn't anchor in all situations. When the bite slows down in midtide, fish will often spread out into the deeper waters on the bay side of the passes. In that situation, basically when you stop seeing them in the passes themselves, drifting might be a better solution so you can cover more ground and hopefully elicit a strike.
Top Keys tarpon passes include (from north to south) Indian Key Channel, Channel 2, Channel 5, Long Key Channel (which is spanned by the old Long Key Viaduct), the Seven-Mile Bridge and Bahia Honda. The silver mullet is the bait of choice early in the season, as large schools move through the Keys, with tarpon and lots of other species in hot pursuit.