St. Augustine Inshore Slam: Redfish, Trout, and Flounder on the Matanzas
The Inshore Slam on the Matanzas River
An inshore slam—catching a redfish, a spotted seatrout, and a flounder in a single outing—is the benchmark day for any shallow-water angler in Northeast Florida. The Matanzas River, running south from St. Augustine along the Intracoastal Waterway, provides the habitat diversity to make a slam possible on nearly any trip from spring through fall. Oyster bars hold redfish fishing targets, grass flats harbor seatrout, and sandy channel edges attract flounder—often within a few hundred yards of each other.
The Matanzas is a relatively narrow, shallow waterway bordered by Spartina marsh, mangrove patches (at its southern extent), and shell-raked shorelines. The tidal range of 4 to 5 feet in St. Augustine creates dramatic changes in water level that shift fish position throughout the day, meaning an angler who reads the tide correctly can intercept all three slam species by fishing the right habitat at the right stage.
Redfish: The Oyster Bar Connection
Where to Look
Redfish in the Matanzas system orient to oyster bars—the crunchy, exposed shell structures that line creek mouths, island shorelines, and the edges of the Intracoastal channel. On low tides, reds feed along the base of exposed oyster bars, picking off fiddler crabs, mud crabs, and shrimp dislodged by the dropping water. On high tides, they push up onto the flooded marsh grass and oyster-covered shorelines, tailing in water sometimes only 8 inches deep.
How to Catch Them
A gold weedless spoon cast tight to the oyster bar edge and retrieved with a steady, medium-speed wobble is the most effective search bait. When you locate fish, switch to a DOA shrimp or live shrimp under a popping cork for a more targeted presentation. Fly anglers throw Clouser minnows and crab patterns on 8-weight rods.
Seatrout: The Grass Flat Ambush
Where to Look
Speckled trout fishing targets in the Matanzas prefer grass flats with mixed bottom—patches of healthy grass interspersed with sandy potholes. These depressions in the grass create natural ambush points where trout sit on the sand, watching for shrimp and small fish swimming over the grass above them. The flats between the Vilano Bridge and the Usina Bridge hold seatrout consistently, as do the wider flat sections south of the Bridge of Lions.
How to Catch Them
A soft-plastic shrimp or paddletail on a 1/8- to 1/4-ounce jighead worked slowly through the potholes draws strikes. Pop a cork rig with live shrimp suspended 18 inches off the bottom covers more water and triggers trout with the popping sound. Topwater plugs at dawn—MirrOlure She Dog, Heddon Spook Jr—produce explosive strikes that make seatrout fishing feel like a completely different sport.
Flounder: The Sandy Edge Predator
Where to Look
Flounder lie flat on sandy or muddy bottom adjacent to structure—channel edges, dock pilings, oyster bar bases, and the sandy patches at creek mouths. In the Matanzas, the channel edges along the Intracoastal Waterway hold flounder throughout the year, with concentrations building in spring and fall. The transition zones where current dumps sand against a grass flat or oyster bar create ideal flounder fishing ambush points.
How to Catch Them
A live mud minnow or finger mullet on a 1/4-ounce jighead, dragged slowly along the bottom with periodic pauses, is the standard flounder technique. The key is keeping the bait on or within inches of the bottom—flounder do not chase upward. When you feel a bite, wait. Flounder grab the bait crosswise and take several seconds to turn it headfirst before swallowing. A premature hook set pulls the bait free.
| Slam Species | Best Habitat | Best Tide Stage | Top Lure | Top Live Bait |
|---|---|---|---|---|
| Redfish | Oyster bars, marsh edges | Low to mid incoming | Gold weedless spoon | Live shrimp on popping cork |
| Seatrout | Grass flats with potholes | Mid to high incoming | Soft-plastic shrimp on jighead | Live shrimp on popping cork |
| Flounder | Sandy channel edges, creek mouths | Outgoing (current concentrates bait) | Bucktail jig with Gulp trailer | Live mud minnow on jighead |
The Matanzas River is part of the Guana Tolomato Matanzas National Estuarine Research Reserve (GTM Reserve). This protected status helps maintain water quality and habitat that supports the fishery. Anglers should follow all FWC recreational fishing regulations and practice careful catch-and-release, particularly for flounder, which have seen population pressure in recent years across the Southeast.
Planning the Slam Day
Tide Strategy
Start fishing two hours before low tide on the oyster bars for redfish. As the tide turns and begins flooding, move to the grass flats and work potholes for trout. Once the tide reaches its mid-to-high stage, shift to the channel edges and creek mouths for flounder on the moving current. This sequence follows the fish as they respond to changing water levels and current flow.
Gear for All Three
- One rod handles all three species: 7-foot medium-action spinning rod, 2500 to 3000 reel, 10- to 15-pound braid, 15- to 20-pound fluorocarbon leader
- Carry a small tackle box with gold spoons, DOA shrimp (root beer and glow), 1/4-ounce jigheads, and a topwater plug
- A quart of live shrimp covers all three species if you prefer live bait
- Bring a net—flounder are difficult to lip, and redfish over 20 inches are easier to handle with a rubber-mesh landing net