Findings from new Bonefish & Tarpon Trust research mirror the observations of guides and anglers in the Florida Keys as well as throughout the Gulf Coast inshore and offshore: the number of angler-shark interactions is increasing, which may have negative impacts on the fish populations and the fisheries they support.
Whether it’s sharks taking a hooked fish, which biologists call depredation, or one that has just been released, which they call post-release predation, anglers and guides all around Florida’s coasts are increasingly frustrated by sharks taking fish either while on the line or immediately after release.
In some reef areas of the Gulf, it’s sometimes very difficult to get a whole grouper or snapper into the boat because the sharks arrive very quickly after a few fish are hooked.
Some charterboat skippers report that some sharks appear to have learned to home in on the noise of boat motors, and will actually follow the boats from one reef to another nearby at times.
If that’s not enough, bottle-nosed dolphin are also getting on in the act, with some areas in Tampa Bay and Charlotte Harbor almost unfishable because “Flipper” shows up as soon as a snook or redfish is dropped back over the side.
The problem is also evident in Florida Bay and the Florida Keys, so much so that Bonefish & Tarpon Trust (BTT) launched the Florida Keys Shark Depredation Project in the fall of 2024, beginning with a survey among anglers who fish inshore in areas from Biscayne Bay south to Key West and west to Florida Bay and the Everglades. Following up on that survey, BTT researchers recently conducted a workshop with Keys fishing guides to pinpoint on the map which areas see the most shark-angler interactions.
Guides and anglers generally report that shark numbers in this area seemed to go up significantly starting in 2014-2015, and have risen more or less steadily since.
Per the BTT report, snook and red drum are the flats fish species depredated most, and lemon sharks are responsible for the most depredations.
These findings, together with the high-depredation locations provided by guides, will inform the next phase of the project: BTT researchers working in the field to study shark behavior, diet, and movement to get a better handle on what has caused the increase in shark-angler interactions.
But it’s likely that there are two basic causes—exponentially more sharks due to widespread shark protection in U.S. waters, and more anglers fishing successfully fishing live bait and chumming with it.
Sarah Hamlyn, BTT Florida Keys Research Associate, works with workshop participants to pinpoint areas on the map where shark-angler interactions are most frequent.
The goal of BTT’s Shark Depredation Project is to identify ways for sharks and anglers to coexist within a healthy flats fishery. BTT can then work with resource managers and anglers to deploy these science-backed solutions to mitigate shark depredation in the Keys. BTT is also looking at this issue beyond the Keys, including its support for the SHARKED Act, a bill that would create a task force of experts to address the depredation problem nationwide.
At Boca Grande, hammerhead and bull sharks gather in numbers when the tarpon school in the big pass, roughly from early May through the first week of July in most years. Sonic studies in the pass have indicated there are literally thousands of adult tarpon in the pass during this period as they feed heavily before heading offshore to spawn. The huge number of fish has inspired a thriving sportfishery for over 100 years—but has also trained generations of sharks that there are easy victims in the hooked or just released fish.
One of the elements in “training” predators to hang around sportfishing boats is most likely the widespread use of scaled sardines both as live chum and as bait for light tackle angling. The tactic puts lots of food in the water, which not only turns on gamefish but also lets the big eaters know that bite-sized snook, redfish and other tasty species are soon going to be wallowing on the hook, easy targets for a quick attack.
There are no easy solutions here, and anglers may simply have to accept that the “tax man” literally is going to have to be paid in some areas. (Incidentally, for those of you who live in the states that got tax extensions this year, tomorrow is the end of the road. Let’s see, where did I leave my 1099’s . . . ?)
