You know a lot more about those tarpon than I do. I think you are fishing around the corner from gallows bay, at the entrance to Altoona Lagoon. if so, I know that the lagoon itself has one of the only shrimp populations (thats what all the peurto-rican guys are after with the nets). Also, the lagoon holds some baby tarpon. I think any huge shrimp imitation would be a good bet, as tarpon everywhere else love them. Also, i know that a lot of them hang out around the point under shade of the marina piers during the day, waiting for the fishermen to come in and clean fish. I dont know what good that information may be, other than that they may be suckers for big, dead looking imitations of sprat or whatever else looks easy.