Summer and winter, Mosquito Lagoon in East Central Florida delivers on its reputation for big redfish and seatrout in clear, shallow water. It’s the autumn transition period—higher tides, cooler water--that throws a wrench into the works.

For fishermen like Capt. Nathaniel Lemmon, an October chill brings welcome relief from summer’s scorching days. At the same time, the guide finds that he has to move to stay on top of fish and adjust his fishing tactics.

Among the most famous flats fisheries in Florida, the Lagoon comprises some 21,000 acres along the Intracoastal Waterway north of Cape Canaveral. About half of that area consists of water three feet deep or less. With no major freshwater tributaries, the lagoon remains salty and sparkling clear most of the year, resulting in lush seagrass coverage. Living close by, I fish the lagoon as often as I can. On any given day, so do dozens, if not hundreds, of other anglers.

The lagoon’s seasonal patterns are well-known to regulars; some practically claim stewardship of individual schools of redfish, casting at the same fish day in, day out. Among fishermen that translates into a good deal of chest-thumping and not a few territorial disputes, but confidence can be shaken by a few cold fronts and a few extra inches of tide.

“As the water turns colder, fish begin to move toward their overwintering areas--sloughs, creeks, basins, canals, cuts and channels,” Lemmon said on a recent trip. I’d joined him to explore these transition fisheries, and we had a successful day, despite strong winds. “These areas serve as refuge during periods of extreme cold, during periods of low tide and low water, or when fish are highly pressured,” Lemmon added.

Tides are another factor—or perhaps I should say, tides aren’t usually a factor. Mosquito Lagoon typically has less than a foot of tidal change each day, but in the fall, the range can be a full foot or so. Fish are prone to be on the move. Lemmon explains:

“If water levels stay high enough on the flats and fish can find refuge in a sand slough, sand spot, or a deep swath along an island and stay relatively comfortable, they won’t necessarily leave the flats to find refuge during colder weather. The fish may be scattered in one’s, two’s, three’s, or pods of 5 to 10 fish but they will ride it out on the flat. If water levels drop too low or become too cold for their comfort, they will then move toward the neighboring deeper creeks, channels, canals and larger sloughs. This is often when you start to find our famed Lagoon schools of 100 to 500 redfish.”

During fall months, we often see rapid fluctuations in water temperature brought about by passing fronts. Schools of redfish and their close relatives, black drum, diverge from their summer patterns.

“If the water warms quickly, the reds and drum break apart into smaller groups during the day and move up into shallower water to feed, only to regroup overnight,” Lemmon says. “If the water stays cool or drops quickly, they may simply hang out in deeper areas all day long.”

During fall, Lemmon prefers to start fishing near deep water, along the edges of creeks, channels, canals and in large sloughs where fish might seek warm water during the cooler nights. He keeps an eye toward shallow water for signs of tailing or feeding activity that may occur as the flats warm. As the morning progresses and the water warms, he moves up onto the flats with deeper sand/mud sections looking for laid-up fish. He still keeps watch toward shallow sections of the flat for feeding activity or the presence of bait. If he finds no bait on the flat, there probably will not be any fish feeding in that area.

When Lemmon and other lagoon vets discuss baitfish, the subject of mullet always comes up. By late October, the fall run of mullet down the east coast draws to a close. Although many anglers think of this run as occurring only in the surf, scores of migratory silver mullet enter the Intracoastal Waterway at Ponce Inlet, move into the lagoon, and then exit through the inlet again to move south in the surf.

“Finger mullet, pinfish, pigfish, herrings and other baitfish wrap up their migration out of the lagoon in anticipation of colder weather that will soon come,” says Lemmon. “Also during this time period, you start to get the first good shrimp runs of fall, when the shrimp are much bigger and more plentiful.”