Fishing the Shipping Channel

Shipping channels are more than merely a deep section of water cutting through a waterway, but are a major feat of engineering design that provides fishing anglers with the best of both inshore and offshore fishing right in your own backyard. If you are lucky enough to have a major shipping channel near you and haven't perfected the art of fishing such a structure, I would highly suggest you read the following and get out for some great fun and bragging rights!

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.

 

In addition, there are many areas just outside the channel that offer varying bottom changes from rolling sand mounds, coral patches, hard swiss cheese bottom, rock beds, and artificial reefs. The areas to explore are vast, as if the 45 miles of channel weren't enough, our vast network of small creeks and channels leading into the nine major ports would give you another thirty plus miles to prospect. If that's still not enough, we have four major rivers and a hundred plus tributaries that flow into the bay, and the miles of flats fishing that's minutes away, but this section is about fishing the shipping channel and I'm getting off topic with all the fantastic fishing areas we have. Back to the topic at hand.
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.

 

Dynamics of a Shipping Channel

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.

 

5) Metamorphic Change: While not common knowledge, severe changes occur daily that alters the entire bottom, and a complete makeover can occur within a month so drastic that fishing a bottom structure in January may very well be gone the following month, or at least be covered up to some degree. Sand and silt carried throughout the channel during tidal flows, and other sediment from rivers and streams dumping into the nearby water settles at the bottom, collecting at a rate of more than a million cubic yards per year in the Tampa Bay channel. That's enough sand and silt to fill Raymond James NFL Stadium to the top 10 times. This is one aspect overlooked by anglers returning to fish their favorite bottom structure they found last season, and one aspect I quickly learned in the beginning stages of fishing the shipping channel. I spent nearly a week scouting a small section of the channel and marking spots that looked favorable, and those spots did produce very well the following days. I fished this particular section in the fall and didn't return until spring, as my winter months had me fishing the river systems. When I returned that spring I did manage to find my ledges, and the structure on top remained virtually unchanged, but the majority of the toe structure had completely changed. In summary, most of the drastic change will occur in the bottom 10 feet of the slope down to the toe, and obviously the bottom. Some of the holes and crevices further up the slope may fill in, but erosion will also open up new crevices. It's a changing world down there, so be sure you scout your area often. The use of a good bottom reader with side and structure scan is very useful here. I use the Lowrance HDS 12 touch to get a great look at what's going on.

 

6) Current: Within the channel you’ll find the strongest tides in the bay. As the tide rips through it takes anything not anchored down and funnels it down the channel. The deeper and straighter a channel is the faster the current will flow. Although shipping channels do not usually have tight bends, they do have designed bends, and as so you will have a calm side and a more turbulent side during tidal movement. The inside bend will always have the weakest current and deposit the most sediment, while the outside bend will receive the faster current, thus becoming deeper through erosion of the channel walls. These areas that receive fast current create fantastic habitat and will hold the best fish in the channel.

 

How To Fish the Shipping Channel
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.

 

It takes a lot of time on the water to even come close to perfecting the art of trolling a channel like this. In addition, you'll need a very good bottom reader that responds quickly and shows a lot of detail. Not many shallow water flats boats are equipped with the right kind of electronics, so most inshore anglers run the channels edge looking for outcrop ledges that may show up on the reader, and then anchor and drop baits. In fact, I take my offshore boat equipped with the Lowrance HDS 12 touch and 2KW transducer with structure scan out so I can accurately find productive spots, and when I only plan on fishing the shipping channel , this is my boat of choice. However, any time I fish the bay my plans are fairly extensive and include a great deal of skinny water fishing, so my 20 foot Hewes Light Tackle sees the bay water a lot more.

 

Within this section of the book you'll read further on water temperatures and seasons, currents and tides, anchored and trolling tackle, trolling methods, methods on fishing the different zones, top and bottom water fishing, tactics and more.