Feature – Islamorada Humps


Hump it Out to the Stream

The seamounts off Islamorada offer as much big-fish action as you are likely to want.

By SCOTT BANNEROT

Palmer, my father, eased the throttle back and spun the helm to the southwest, positioning the venerable 18-foot Seacraft into position for the first drift across the Islamorada Hump.

The sea surface, becoming more of a mirror as the late afternoon sun slid lower, was barely wrinkled with light ripples, a stark contrast to the wild seas that can develop over the seamount projecting up into the flow of the Gulf Stream. The characteristic Back Rip, often a line of foaming stationary breakers over the downcurrent crest of the Hump, was only a slender, dark zone of 6- to 8-inch wavelets, visible to the northeast as we settled in to drift.

I scooped a net full of pilchards from the livewell and hooked four to a 50-pound teaser line, then sent them out behind the boat. Palmer kept the bow southwest into the current, idling gently in forward gear as the four terrified baits darted around 30 feet back from the transom. I tossed a second scoop of pilchards back on top of them. The free swimmers clustered around the teaser–a distinct ball of bait creating an irresistible silhouette for bruiser blackfin tuna cruising 20 to 80 feet below.

Three more baits on 20-pound spinners, armed with the same hooks as the teaser and no leader, one freelined back yellowtail snapper-style by my wife, Wendy, and the other two held at the boat ready for casting to the teaser, and we were set.

Suddenly, an explosion of foam and pilchards jolted us like an electric shock. A pack of blackfins rocketed vertically through our living chumball, crashing through the calm surface to create a 5-foot-high spray of pilchards and white flecks of seawater. Palmer, and our friend Liz McCutcheon, flipped their baits into the melee and loose coils of monofilament immediately began ripping loudly off the spools. Palmer closed his bail after a fast count, wound like a madman, and lifted his rodtip sharply when he felt resistance. The rod doubled and the drag screamed. Liz, on her first tuna outing, was in a state of shocked silence as line piled off her spool. I backhanded the bail closed and everything else took care of itself, the blackfin coming to the end of the slack at 60 mph and impaling itself, nearly snatching the rod overboard as Liz let out a squeal of excitement.

Twenty minutes later, Palmer’s fish had gone through the leader only 25 feet away from the gaff, Wendy had pulled the hook on a third fish, and only Liz’s fish remained, flashing silver in the indigo depths. Beads of sweat covered her forehead and upper lip as she did a good job, with no shortage of advice from the peanut gallery, lifting the rod slowly and firmly in short, even strokes, dropping and reeling, slowly gaining on the dogged but tiring fish.

Mindful of Palmer’s fish now swimming away, I leaned over the gunnel with the gaff and stuck Liz’s fish on the inside of one of its circles five feet down, and snatched it aboard. It went 22 pounds, a great first tuna on 20-pound spin.

We finished out the afternoon with three more drifts. The fish continued to respond well to our technique and we knocked off after Palmer came through with a fat 28-pounder to wrap up the day.

Seamounts such as the Islamorada Hump are quite simply mountains rising from the sea floor. When located in current like the Gulf Stream they present an obstruction to the prevailing water flow, causing it to “squeeze” around and over it. The vertical component of this squeezing action sends water from deeper layers boiling to the surface, along with a menagerie of organisms not normally concentrated near the surface–squid, preyed on directly by gamefish, as well as zooplankton, fed upon by schools of flying fish which in turn become prey for surface predators like dolphin, blackfin tuna, and an occasional wahoo and billfish.

Most anglers know that structure and associated turbulence create productive feeding areas for target species, but many don’t extend the analogy to the quest for live bait, the biggest single denominator for a successful Hump trip.

Off Islamorada the primary bait species are pilchards, cigar minnows, and ballyhoo. Mackerel scad (dubbed “speedos” by locals) are sometimes cast netted, but are more often captured by circular hoop nets suspended under chumbags and lifted quickly, or by hair hooks, the main method for catching blue runners and grunts.

Most successful bait fishing results from looking for the bait schools, both with fishfinder and by scanning the sea surface, and also looking for telltale bird activity. One or more hovering royal terns, occasionally dipping or diving in the vicinity of Hawk Channel, is a sure sign of pilchards–so are diving pelicans.

Once you find them, motor upcurrent and drop balls of sand/chum mixture downwind, drift quietly into position, and cover the sand with an artistic, pancake-shaped throw of a 12-foot cast net.

What if, despite your best efforts, you’ve only caught 30 pilchards, or, worse, none? As long as it’s not too late in the spring, go to the reef edge and scout for ballyhoo by riding along as high as your boat allows you to safely stand until you flush a sizable school, back off the throttle, toss the chumbag over and make a large circle before anchoring to wait them out. As they first appear in the chumslick, float back some hair hooks with tiny pieces of bait two feet or so behind a small clip-on bobber. Hair hook as many as you can (these will outlive most of those cast netted), then throw the net when they get close enough.

Live ballyhoo slow-trolled or drifted well back from your boat will attract some of the biggest blackfins over the seamount. Use a 5/0 Mustad 94150 hooked through the skin just aft of the beak and 30-pound leader, and drop back longer. Use the same technique if you don’t have enough pilchards to chum.

Although livebaiting is the most popular method on the Hump, it isn’t the only way to score. In fact, there are times during the October through May season here that it may be a better battle plan to skirt the crowds of livebaiters and work some artificials.

Quarter-ounce feathers in pink, blue-and-pink, blue-and-white, combinations of black-and-red, pink, silver, and purple and armed with 5/0 to 7/0 hooks on straight 30-pound-test leaders work well but sometimes appeal only to smaller blackfins and skipjack tuna. When this happens, you can often target bigger fish by switching to 4- to 6-inch plastic squids rigged with an internal egg sinker, in amber or pink; 51–2-inch soft headed trolling lures in pink or blue-and-white, or black-purple-silver, also rigged with an egg sinker ahead of the hookeye; or a flying fish lure rigged with a double hook. Troll these larger, splashing surface lures at speeds where they pop, skip, or break surface at least once every five seconds withou
t skipping wildly out of the water and flipping around. Subsurface, slow-trolling jig heads baited with black plastic bass worms, glow worms, curly tails or various plastic eels and the new plastic baitfish bodies, can yield excellent catches even on the days when the livebaiters aren’t doing well.

Be sure to run at least one on your downrigger, 60 to 80 feet deep. Each time you hook up, cast one of these soft weighted plastics out behind the boat near the hooked fish, let it sink 60 feet or so, and retrieve–you’ll often nail a second fish.

Another tactic that produces relies on dead bait.

Contrary to popular belief, blackfins can be effectively chunked at the Hump. Cut 1 1/2-inch cubes of fresh skipjack or blackfin, toss in a handful along with any entrails, and freeline a baited 1/0 to 3/0 hook on straight 20- or 30-pound test in with the chum. If you’ve caught an amberjack, do the same thing with the roe, starting your drift near any commercial amberjack boat. At times the tunas get so focused on amberjack entrails discarded by the commercial fleet that they are hard to catch on live bait. Switch to light wire leaders if you start getting cut off, as there can be nice wahoo hanging around as well. Don’t bother trying any of this with bait that has been frozen.

Speaking of amberjack, this species is one of the available alternatives to blackfin tuna. Many a day has been saved by dropping a live blue runner or grunt down deep.

Amberjack fishing also has a tendency to produce vivid memories, but few are as vivid as one held by an anonymous customer of a now-retired Islamorada captain, whose name we will also omit to protect the guilty.

The captain and his mate had managed to produce an outstanding morning of offshore action, including a sailfish, one wahoo, and a bunch of school dolphin, none of which was substantial enough to fulfill the greenhorn customer’s preconceived notions about big-game fishing. The somewhat crusty, senior, and now infuriated skipper set a course for the Islamorada Hump, quietly directing his mate to rig an 80-pound outfit with a pound of lead and four circle hooks, shoulder harness the guy securely to it, sit him in the fighting chair, lock up the star drag, then freespool four live baits down by hand–and not to step back and throw the reel into gear until he was sure all four baits had been swallowed. Needless to say, when the reel was engaged, the surprised man was jerked bodily out of the chair and skidded rapidly and unceremoniously to the transom, which he slammed into with authority, saved from plummeting overboard only by the mate’s firm grasp on his belt. Pinned now to the covering board, rod butt digging sharply into his substantial gut, he screamed hoarsely for the mate to cut the line. The captain interjected loudly,

“We can’t–we’ve finally hooked the monster you wanted!”

After a few more screams he nodded to the mate, who quickly cut the line. This catapulted the beet-red angler backward onto the deck, silent and shaken.

That story took place in early May, near the end of the time when amberjack spawn each spring at the Islamorada Hump, 409 Hump, West Hump, and Key Largo Hump. There is a chance of catching one almost anytime of the year at these spots, but February through April represents the peak.

When they are most densely packed in March and early April at the Islamorada Hump, it can be impossible to get a live bait of almost any kind deeper than 80 feet.

The standard rig is a 3-way brass swivel with 12-foot, 50- pound-test leader and 12/0 offset circle hook, and usually eight to 16 ounces or more of lead. Start the drift by leading the Hump to the southwest at such a distance that your bait enters the strike zone as you pass over the 290-foot deep peak. Bounce bottom (this will take some practice for the novice), then quickly crank up 30 feet or so before you hang bottom. When you feel the slow, strong pull of the take, don’t snatch back–lower the rod to horizontal and wind hard, and you’ll usually be hooked up. You may have to look around the corners and sides to find them when they are not plentiful, and time your drops to deliver the baits to them.

During the hottest bites, fishing deep jigs can be very effective and allow you to use lighter tackle. Amberjack fishing generally stays good into early summer at the 409 Hump. Beware of stringent bag limits to protect this now hard-fished species–you can only keep one in Monroe County–and release any unwanted fish. Carefully puncture the air bladder first by inserting an ice pick two inches behind the pectoral fin until you hear the sound of escaping air, press to fully relieve the pressure, tag, and release.

Another Upper Keys seamount specialty, practiced effectively by only a few boats in the charter fleet, is livebaiting wahoo. Mackerel scad or feather-caught juvenile blackfin and skipjack tuna are the usual baits, slow-trolled on light wire leaders with stinger hooks. The same rig deployed off a kite is excellent as well.

Deep dropping can also be excellent in the areas surrounding the deeper seamounts, and right on top during times when the amberjacks and sharks are not plentiful, such as mid to late summer and early fall. A real potpourri of species can be captured depending on the location and depth, including pink porgies, gray and golden tilefish, snowy and misty grouper, yelloweye, vermilion and blackfin snapper, among others. This is another area where it is particularly important to catch only what you need and not overdo it, as these spots can be fairly easily decimated and do not regenerate very quickly due to slower rates of growth and reproduction for many of the species. Carefully check current federal regulations recently enacted to protect some species in this fishery, and remember that mortality rate is virtually 100 percent for everything you bring up from these depths.

Quite a few billfish are caught annually at the various seamounts. Sailfish and occasionally white marlin come up to live bait chum thrown out for tuna. I remember an afternoon at the Islamorada Hump when a charterboat had raised a white on the livebait teaser. The captain loudly narrated the events over the radio as his mate first cast inaccurately and then somehow missed a take on a subsequent cast. This gave a neighboring charterboat, alerted by the radio grandstanding, time to maneuver for a throw at the now very excited marlin, whose characteristic blunt dorsal was clearly visible above the surface as the fish sliced through the free-swimming pilchards. You can guess the rest–the boat with the quiet, focused captain hooked and eventually caught the 65-pounder and tagged and released it. The moral of the story is always have a pitch rod ready, rigged with 50-pound leader and a sharp hook standing by ready to bait and cast (and don’t waste time cluttering the airwaves when you could be fishing).

A few blue marlin are caught each year around the seamounts as well, usually in the course of dolphin fishing. At least one was caught accidentally by a charterboat dropping a heavily weighted rig for amberjack. There is very little directed effort in this category, i.e., slow-trolling live mullet, school dolphin, skipjack or blackfin tuna, or mackerel scad on 300-pound-test mono leaders and an
appropriate rod and reel (for Islamorada, 50-pound tackle will cover you), or running a full spread of billfish lures or lure-bait combinations and teasers. Most blues are seen and caught from April through summer. Here again, a dedicated rod ready to bait and deploy can often be the difference. There is usually time to bait a billfish that has chased something smaller you are bringing in, or that has been sighted lurking around the edges of a dolphin school, but not if you have to rig up first.

Fact is, while there is usually something biting over the humps in the Gulf Stream, you’re never sure just what you may get into. No matter how you are rigged, you probably can’t cover it all–but it’s a cinch the tackle you do have will get a good workout all the same.


How to Get There

Here are the GPS and loran coordinates for navigation to four productive seamounts off the Florida Keys. Latitude and longitude are in degrees, minutes and tenths, so set your GPS unit accordingly. The humps are fairly substantial bottom features, and slight aberrations in GPS or loran accuracy are easily remedied by keeping an eye peeled for rips formed by current changes, birds feeding overhead and other boats working the area. A depthfinder will also prove useful.

Coordinates given for the Key Largo Hump, listed below, are based on a rough midpoint; it’s actually less of a hump and more of an “S” curve between 280 and 330 feet off French Reef.

Key Largo Hump
GPS: 25-00.661′ N; 80-16.8′W
Loran: 14133.7; 43217.8
Depth: 280-330 ft.

Islamorada Hump
GPS: 24-48.175′ N; 80-26.674′ W
Loran: 14098.3; 43266.4
Depth: 294 ft.

409 Hump
GPS: 24-35.5′ N; 80-35.5′ W
Loran: 14064.6; 43311.8
Depth: 409 ft.

Marathon Hump (West Hump)
GPS: 24-25.528′ N; 80-45.328′ W
Loran: 14032.3; 43358.5
Depth: 516 ft.

FS