Thermocline Cobia

Reef Cobes

When cold water hits the beaches of northeast Florida, cobia hunters head for the reefs.

By Terry Lacoss

For much of last summer, a persistent thermocline dropped nearshore water temperatures into the high 60s along the northeast Florida coast. Offshore livebait trollers from Canaveral to Fernandina were faced with the increasing problem of not being able to find good numbers of menhaden along the beaches and inlet mouths. Farther offshore, however, bait schools were plentiful over wrecks, artificial reefs and other structure. Many fishermen adapted to these changes, running offshore to catch live baits.

What they found out here—in addition to kingfish, the expected catch—were cobia. Lots of cobia, and in a very aggressive feeding mood.

Capt. Benny Hendrix aboard the charterboat Miss Val logged several good trips last summer. On one memorable day, he recalled a young man looking into the water and saying to his father—who was fighting a cobia—“Look Daddy, there are a bunch of sharks in the water!”

Grinding chum calls up the big ones.

“I looked around to see eight cobia swimming right behind the father's 48-pounder!” Hendrix said. “We ended up landing three in the school, while casting big saltwater jigs tipped with squid.”

Cobia are naturally curious, but they seem even more inquisitive during coldwater events, when finding a meal at inlets and beaches becomes a challenge. Faced with satisfying their appetite offshore, cobia become easy targets for reef fishermen.

It's common for them to follow a hooked fish, but many times they'll swim up from a deepwater fish haven when the sound of a boat approaches. This seems to happen most often during the morning. As the sun begins to rise on deepwater fish havens and the silence of night gives way as sportfishing boats arrive, cobia are quick to investigate. No one can say for sure why they do this; perhaps the engines sound like fish feeding.

We observed the phenomenon one day last July while fishing a large area of live bottom. My son Terry had anchored our 32-foot boat just south of the St. Marys shipping channel and only eight miles offshore.

“Break out the blocks of ground chum,” he instructed our fishing party. “There should be some good-size cobia hanging around this live bottom and kingfish, too. But we need to chum them up first.”

Wilson Tennille quickly opened the large cooler and handed Terry two blocks of frozen chum. These went into mesh bags attached to each gunnel of the boat. Slowly, bits of chum broke free and drifted with the current to the reef below.

After setting out a spread of live Boston mackerel and Spanish sardines, I went to turn off the diesel engines.

“Leave the port engine running,” Terry suggested. “There should be some cobia nearby and the sound of the motor running is always a good way to attract them.”

So, with one engine running, we began waiting patiently for the first strike of the morning. But after 30 minutes and swapping tired live baits for fresh ones, we were still waiting.

“I know how to call them up,” said Terry David. “Sometimes it takes a little noise to let these kings and cobia know where they can catch an easy meal.”

He soon engaged the transmission of the port engine, allowing the boat to jump forward on anchor and also creating a big wash behind the boat. He did this two or three times, then returned to the cockpit and watched our livebait rods for any signs of action.

The propwash trick did it. Wilson grabbed a deeply bent rod from its holder and played a speedy gamester. A pair of desperate runs ended with a 20-pound kingfish at boatside. Seconds later, another fish hit one of the freelined live baits and once again, Wilson leaned back into a fish—this one a 40-pound cobia.

Time and again, anglers have reported similar days offshore. I remember when we used to catch a lot of cobia in the St. Marys ship channel, and around the bait pods just off the beaches and inlet. But during the past few fishing seasons, it seems as though the nearshore cold water drove the cobia to offshore fish havens. Maybe change is good: Based on reports and from what I've seen, I'd say the summer of 2003 was the best cobia season we had in a long time.

Another neat summer trick for offshore cobia involves netting silver mullet in the tidal estuaries of northeast Florida and then targeting ledges and wrecks 5 to 10 miles offshore. Using a 5-ounce jig, barb a mullet through the open mouth and right out through one of the nostrils. Drop the rig to the bottom, reel up some 10 feet and set the rod in a transom rodholder. Barb two other mullet through the mouth with single 7/0 circle hooks and flatline them 30 to 50 feet off the transom. I prefer to set the drag so that line will feed off the spool freely, without backlashing. When a cobia takes the bait, allow a few seconds, then push the drag up and set the hook.

Once a hooked cobia is brought to the side of your boat, be alert and have a couple of extra rods ready to cast live baits or lures to other fish that might be tagging along. Also be prepared for a quick and clean gaff shot. Things can get messy when you bring a cobia into the boat. A fish that appeared exhausted in the water can suddenly turn into a twisting, thrashing crazy fish. Instruct someone to open the fish box before you sink the gaff—and have them slam and secure the lid the instant the fish lands in the box. Gaff the cobia right behind the head and with an upward motion, swing the fish into the boat and right into the box.

Look for some of the best offshore cobia action on fish havens within 5 to 10 miles of the many inlet mouths of northeast Florida. Included are the Daytona, Matanzas, St. Augustine, St. Johns, Nassau and the St. Marys inlets. Many of these structures are marked with GPS coordinates on local offshore fishing charts. Keep in mind that tidal effects of nearby inlets move good numbers of baitfish over these nearby fish structures.

So, when the effects of a summer thermocline hit the beaches of northeast Florida, look for cobia fishing to improve at nearby offshore reefs. Be sure and ring their “dinner bell” too! - FS