Tracking Key Tarpons
Stand on the bow of a skiff staked off in the Marquesas west of Key West and watch for a school of tarpon. They're nearly invisible in the clear waters, their silver-blue bodies hidden but for the shadows they cast on the sea grass. These fish are moving into the Keys for their annual migration and spawning along the coasts of Florida, patterns that have been ongoing for more than 80 million years, scientists say.
During February and early March, the Florida Keys sees Florida's first wave of migratory tarpon moving into its waters. The numbers of those fish reach their peak sometime in June. For those weeks, tarpon roam the flats, channels, harbors, and basins north and south of the island chain. Resident tarpon, both juveniles and larger fish, can be found around Key West year-round.
One of the greatest spectacles in tarpon fishing also happens in May or June: the palolo worm watch. The exact timing is unpredictable. Palolo worms live in the substrate of the nearshore ocean; when they emerge during full moon nights in late May or June, the tide carries the hatchlings out to sea and calls in tarpon for a feeding frenzy. It's a supreme opportunity to take a tarpon at the surface on fly or artificial lure.
Another popular technique to catch tarpon during the migration is to anchor at bridges and chum in the channels where the tarpon linger, drifting back live baits or casting lures or flies to the fish. One night it's hot at Seven Mile, the next at Bahia Honda, or Niles Channel. Local guides are adept at releasing anchor to follow the fight of a tarpon, which might take their skiffs far from the bridge, but if you try this yourself, be aware that many large sharks, including bull and hammerheads, lie in wait to eat tired tarpon.
On the flats of the Marquesas, and flats closer to Key West such as the Tower Flats and the Seven Sisters, tarpon will cruise over the flats and along the edges of the bordering channels looking for baits washed along by the moving tide. Anglers will stake off their boats in a good position to cast to the channel edges, and some anglers will team up: one to pole the skiff and one angler in the bow to cast when a fish is spotted. Tarpon might get hot and cold during a falling tide, and if action slows you can move to another flat to look for them. As a rule, the deeper water gives the tarpon more room to evade predatory sharks and allows them to get a bit more aggressive in their search for food.
In the channels, tarpon can be marked by depth finders and drifted live baits, a similar technique used by anglers in Key West Harbor, where large schools of tarpon gather in the deep water during the migratory season. If you're fishing in the harbor, be well aware of the busy boat traffic patterns and jet ski riders. This is not fishing for the faint of heart and may be best left to anglers and guides experienced in the Key West Harbor game. There are plenty of channels, like the Northwest Channel, Calda Channel, and Bluefish Channel right by Key West where you can fish in less crowded waters.
To the flats, anglers take spinning gear like the PENN Spinfisher VI 6500, fly rods and reels, and plug-casting gear. They generally use 20 to 30 pound monofilament mainline and 6 foot leaders of 20 to 80 pound fluorocarbon lined on strong rods like the PENN Carnage II to handle a big tarpon. Reels should hold at least 200 yards of line.
If the fish are finicky, lighten the leader. Around the bridges, tackle gets even heavier. A good choice is a PENN 12 International VISX with a Carnage II rod to keep the tarpon from running into the bridge pilings and breaking off.
It's only in the last couple of decades that scientists have begun to understand much about where these tarpon are coming from and what they're doing. The truth is, our interest in tarpon is only a tiny blip on the species' 80 million year history, but now fishery scientists are trying to figure out how to best keep the species and its habitats healthy.
One of the leading Florida authorities on tarpon biology and migration is Professor Jon Shenker of the Florida Institute of Technology. Professor Shenker is also a biologist with Bonefish and Tarpon Trust, an organization which is leading the way in protection and understanding of the species.
"We haven't really known that much about their migratory patterns until the last few years," says Shenker. "We are finding many surprises, that for example some tarpon hang around the oil platforms off the mouth of the Mississippi, and it's been documented that some pretty big schools hang around these platforms all winter long. Unless you're down there diving with them, no one really sees them though."
Professor Shenker himself is looking at some historical samples of tarpon larvae collected over the last 20 years from SEAMAP, run by National Marine Fisheries Service and the Gulf Coast Fisheries Management Council. The SEAMAP program sends one of its large research ships out to survey the larval fish populations on the western coast of Florida in the Gulf.
"I'm going through their records and discovering where the larvae were found. Records indicate that in the month of May, the tiniest tarpon larvae were taken on the western edge of Florida Keys' habitats. A month or so later, the smallest tarpon larvae were occurring off Florida's middle coast, way offshore of Boca Grande and Tampa Bay. In addition to the northward migration, it seems that the fish might dash offshore to spawn and then continue north. In August, researchers found tarpon larvae off the Mississippi River."
A major threat to tarpon is destruction of their nursery habitat, says Professor Shenker. "The babies live in backwater sloughs and these are the areas that are going to be most impacted by humans. We have to develop management strategies to improve connectivity for all life stages, from early larvae getting into these nursery habitats to older juveniles getting out.
"Ultimately," says Shenker, "we want to work with our colleagues in other areas to predict where the baby tarpon are moving into now to give them a baseline for their students to look at 10 years down the road. That way, they'll be able to see if these habitats become better for tarpon in the future."
Slowly, scientists like Shenker are contributing to a more thorough understanding of the species. Certainly, the more that we know about tarpon ecology, their migrations, and their habitats, the better the chances are that the fishery for them will continue to be robust for future generations of anglers.