Fishing the Shipping Channel
Shipping channels offer year-round fishing for those that know how to fish such a place, though it's not as easy as going offshore and dropping a line down. From maximum size grouper to huge tarpon, kingfish, snapper, cobia, seabass, and many more species, the shipping channel gives you that offshore experience without the long rides, expensive fuel charges, and potential dangers that going offshore entails. In fact, as structure goes, the Tampa Bay shipping channel provides a much greater topography in a condensed area compared to the Gulf waters. The channel has a 20 foot ledge while the average Gulf ledges in 100 feet or less of water are 3 feet. Toss in all the undercuts, rubble, caves, artificial reefs, hard bottom holes, inside pockets, and you've got yourself the perfect environment for big and plentiful catches.
On the Gulf coast we are forced to travel beyond 50 to 200 miles at times just to get our hooks in a gag, but within minutes and a few miles you can be enjoying some of the same bent over the gunwale fun that the offshore anglers do. Many of the large offshore species make shipping channels a year round home, and I've been on the better end of the battle many times with 20 plus pound summer gags, and many 12 to 15 pounders.
This section will cover the topic in general so as to apply to the many shipping channels around Florida, and the country for that matter, but since we have a very nice system here in Tampa Bay that produces very well, let me first tell you a bit about it.
I grew up fishing the bay, and having my boat docked on the bay side has given me the chance to discover how productive the channel really is. I am amazed at the few boats I see when heading out to the channel, and those that are fishing the channel are condensed to the south end nearest the skyway. While that certainly has been a known area, some of my biggest fish have come from other places in the bay.
Stretching 45 miles from its starting point 20 miles offshore, the Tampa Bay shipping channel extends another 25 miles inland from the buoy near Egmont Key to the cruise ship docks at Channelside in Tampa. There are three channels that branch off the main channel with very well structured rocky edges and debris riddled ledges. That's 90 miles of deep water and amazing fishing structure.
The information you read here will help you in any deep water shipping channel, as they are all designed for one purpose and all cut the same way. The only foreseeable difference is that I may discuss certain species, times of the year, and bait choices that apply to the Tampa Bay shipping channel and may not apply to your area, but are easily modified with some local knowledge. In general, the targeted species is the gag grouper and the time of year is spring and fall unless otherwise noted.
1)Depth: Most major shipping channels are forty plus feet deep, with adjacent depth changes as great as 20 feet or more. In the Gulf, most ledges average under 3 feet or less inside the 50 mile line, but the vast depth changes around structure in the shipping channel produces some amazing catches, and those that fish the channel know what I am talking about. As we all know, abrupt changes in depth equal good fishing. These abrupt changes offer the fish good ambush cover, good food variety, comfortable temperatures, and safety.
2) Slope Structure: As you follow the slope of the channel you’ll find outcrops, holes, crevasses, deep caves and undercuts as shown in (fig.1 A-E). This vast makeup of structure is from using explosives to remove large rocks, normal dredging, natural voids, and erosion. At the toe (fig.1 E) you’ll also find plenty of rubble that has loosened from the slope and edges and scattered about in the toe zone.
3) Ledges: Shipping channels all have ledges at some depth from the cutting of the channel. Cutting through the seabed exposes various types of material from sand and dirt to limestone and shell, and opens voids above and below the solid rock, as well as within the rock itself. In the Tampa Bay channel, there are layers of limestone at various depths, and one particularly large layer about 35 feet below the surface. The current begins to wash away the weaker sediment, thus forming a ledge like the one you see in (fig.1 D). In addition, the limestone has many voids (hollow pockets), that when cut through reveals small to large holes and crevasses, also shown in fig.1 D)
4) Sidecast: Along the channel’s edges (fig.1 C) are various sized rubble piles of dredged material known as sidecast, simply meaning that some of the dredged material ended up on the edges just before the slope. During the cutting, or on a maintenance dredge, these areas become very pronounced. As the sidecast material settles, the smaller sediment gets washed away or settles down between larger rocks, while some of it rolls over the slope.
There are three ways to fish a shipping channel, either by trolling, controlled drift, or anchored. Regardless of which one you choose to start, trolling and drifting will eventually turn into anchored fishing, at least it does for me. Both trolling and drifting are two methods to cover more ground in hopes of finding the fish, at which point it's downrigger up and anchor down. Which one you choose to start with is up to you, but by far the hardest is trolling due to the many aspects that need to be in sync such as keeping on course by watching your bottom reader, controlling your speed, finding activity, and dealing with snags, and that's before you go into fish on mode.