The sharking and tarpon fishing is what is best off of the bridges. Snook fishing can also be very productive if you know what you are doing. When the snook fishing is good the tarpon tend to be pesky and persistent bait gobblers. The sharking is good on Long Key Bridge, seven mile, & channel 5 bridge. One productive snook techniques is pitching a freelined hand pick shrimp slightly upcurrent of snook that are waiting in ambush. If you have a lantern (which you should) tie it up to a appropriate rope and suspend it near the water it will attact greenbacks and make shrimp visible.....it will also attract feeding snook and tarpon. You can sabiki greenies and pitch them on a flat line for snook & tarpon or place them on a fish finder rig if you are after tarpon (using just enough lead to hold bottom). Chanel 5 is best for this snooking and tarpon because you are closer to the water on that bridge.
Remember this bridge is on the Gulf side of the US1 so this will work best on a incoming tide (to avoid being run under the bridge or towards the short run to the piling of the US1 bridge and getting cut off). If the moon is high and making the bridge cast a shadow towards the gulf side all the better. The fish will blow up on either side of this shadow line. The folks that cast hand picks (huge shrimp) to snook can tell with one look if a fish is a snook or tarpon. I used to joke with the guy who taught me this and tell him he could probably tell me how many scales each fish had as his ID of individuals was incredibly accurate even down to the approximate size (within inches) of the fish he was targeting.
Sharking is a topic unto itself but I will only hit the highlights of bait and tackle for this post. For shark bait noting beats cuda in the keys. Rays and eels are Ok alternatives in a pinch but fresh cuda is king ding a ling if you are after grey suits. Catching this bait is what you will do all day as you wait for the sun to set to get your shark baits out. Don't overlook the early evening shark bite as the sun sets but hookup ratio is always best at night. I won't bore you with cuda catching techniques (or give away all my secrets

) but I will warn that some days you would give a nut for a few fresh baits if you goal is big sharks.
Tackle for bridge sharking begins at a 6/0 and up. We have had 9's and 12's spooled and even though they seem like overkill on a 120lb blacktip you will be glad to have the capacity on the big bulls that run 300lbs+. 6's should have 50lb mono, 9's with 80 or 100lb and 12's 120lb or whatever you back and bulk can handle.
I would type more but I need to get some things done. Hope this helps and if you have questions just ask. :fishing: