Offshore thermocline: We are still dealing with a thermocline in the gulf. This layer of colder water, which generates lower-than-normal visibility, usually dissipates by late spring. The current one starts at about 80 feet and goes out past 200 feet from west of St. Petersburg to west of Naples. The bait is tired of the lower temperatures and has moved or stayed above the colder water. In 150 feet, the thermocline is about 60 feet deep. The cooler bottom water has forced most of the larger bottom fish to move to deeper water or come in to very shallow water. It's summer, so the bigger fish have moved to the deeper stuff. Gag groupers bigger than 50 pounds have moved to water 300 feet and deeper.
Tactics: The heavy activity is situated just above the colder water. On my last dive, to 170 feet, amberjack, snappers, grouper and African pompano swarmed just above the thermocline. Try to hit wrecks and other tall structures that allow the bottom fish to feel safe. This way, you can hunt or fish off the bottom, where the fish are.
Bill Hardman teaches scuba, spearfishing and free diving through Aquatic Obsessions Scuba in St. Petersburg and can be reached at (727) 344-3483 and firstname.lastname@example.org.