Speckled Trout in Deep Hole

Why Trout Seek Deep Holes

Do you know why speckled trout seek deep water? The answer can help you better understand their behavior.

shad rig speckled trout two

It is knowledge of the water, not state-of-the-art equipment, that will catch fish every time.

I have been sitting on the bow of my boat cross-legged, staring at the water. I have a rod in my hand, but the line is reeled in. Behind me on the deck are several speckled trout, flopping around as I had just pulled them from their marine environ.  As I stare into the turbid water of the Biloxi Marsh, it’s almost as if I can see it. The visual taking place in my head most closely matches what is actually happening underwater. I make a note to myself before starting the motor and pulling up the anchor. As the bow begins slicing fog I contemplate what happened back there.

The spot I was fishing had water that was 24ft deep. It was in a bayou that served as a main artery of the surrounding marsh and I had slaughtered untold amounts of trout there over the years. There were days that fish simply didn’t show up, but for the most part this venue was something very attractive to speckled trout. The key feature that separated this “spot” from others is the deep “hole” it possesses. Why do trout like this hole? How can I find others like it?

Stable Temperature

If you have ever been diving then you know that the deeper you go the more cold water becomes. It may not be gradual but could be sudden in the form of a thermocline. Initially, it doesn’t make sense for a trout to seek colder water when it is trying to survive during winter months, but consider how much more fluid air is than water. Cold air can move in at the blink of an eye and cool down shallow water in a hurry. With trout, it’s not really so much the cold temperature that could kill them, but the sudden change in temperature. At the bottom of these deep holes lies water unaffected by drastic temperature changes. This water is “safe” because it is stable. Think of them as a “bunker” that trout can run to get out of bad weather.

Some have also said that there is a heat source geothermal in nature at the bottom of these deep holes. Without testing for this, I can only take this with a grain of salt.

Stable salinity (more salt)

Fishing around the Mississippi River will allow one to quickly realize the differences between fresh and salt water. One has salt, the other doesn’t. Saltwater is denser then fresh water, causing fresh water to float on top. But there is a caveat here a lot of people miss: some saltwater is saltier than other saltwater, and the saltiest of saltwater will be pulled to the bottom by gravity. If you look at our Fishing Planning page, you will discover the MP41 Chevron station that provides these figures. (UPDATE: this station is dead, as per this post) The station records in real time salinity levels at the top and bottom of the water column. Take a quick look and you will see that the saltiest water resides at the bottom.

So how is this relevant? Without delving into the deeper aspects of spotted sea trout behavior (and I am no marine biologist, just an avid fisherman) it is readily apparent that these species of trout prefer clean and salty water. Salty water readily provides a stable environment for trout to reside in. When trout are hiding out from bad weather and battling cold temperature, salty water gives them an edge they can use to survive.

It is winter time now, but this “stable salinity” idea also lends credence to what we see with bigger trout during the summer time. I don’t want to take anything away from another article that covers some of this, Three Sad Reasons Florida Will Always Have Bigger Trout. Deeper water provides the salinity levels a larger trout requires and also provides the stable temperature trout require. Consider that this time it is hot and speckled trout seek cooler temperatures, preferably in the shade. It comes as no surprise that trout, when not actively feeding, cling to the bottom inside of structure like gas platforms. This lends credence to my next point.

Security (not skylining themselves)

I can’t be for sure that this is a factor or not, but it is something I have contemplated. While trout somewhat resemble an apex predator, they are still easy meals for other animals higher in the food chain. Consider how baits we use are being “skylined” when viewed from the bottom of the water column, making them easy targets. Their silhouettes give away their position. It is easily understood how fish would want to avoid this predicament. When trout hold to the bottom of a deep hole, there is no way they can be skylined. This further underscores why deep holes provide great habitat and security for a speckled trout and why they prefer to use these underwater terrain features.

Hydrodynamic efficiency (holding to the bottom)

It would also seem to me that it would be easier to hold in one place if water isn’t flowing around one side of the trout body, but I could be wrong. This is a guess on my part.

Warming areas and baitfish nearby

Almost ALL deep holes I fish in the winter time have a nearby shallow water area. Some of them are oyster reefs. Trout will come out of the protection of their deep holes not only to feed in the shallow water but also to catch the warming rays of the sun. If I don’t catch fish in the deep water, I will move to the nearby shallow water. Often I have been slaughtering trout in the shallow water while people fishing the associated deep water don’t catch anything. This has also happened first thing in the morning.

These trout and redfish were caught before 8am in the morning on a very cold December morning.

This limit of trout and a redfish were caught before 8am on a very cold December morning. They were caught in water about 3-4 ft deep adjacent to an area with water about 12ft deep.

What are some things we can take from this and apply to our trout fishing? What key elements make good winter spots “good”?

  • deep water
  • nearby shallow water
  • moving water

Moving water is important. Trout love moving water and seem to hate it when it is not moving. In fact, they shut down when the water is not moving at all. I’m sure there are several reasons as to why, but one I’d like to mention is that moving water brings bait to them. In fact, check out this video to see what good moving water looks like.

I have noticed that large schools of trout do not prefer locations where there is little water. They instead prefer areas where there is a lot of water, areas like main bayous, mouths of bayous, and structure in bays like oyster beds and underwater “humps”. That’s not to say I have not caught loads of trout in “small” water that are suitable for 1-3 man limits, but I generally find the larger schools suitable for 4-6 man limits in “larger” water.

Biloxi Marsh

Oyster beds have done very well for me. Rather than cover that topic again, I suggest you read this simple article about oyster beds.

I left that spot with a better understanding of why trout prefer to seek these deep safe havens. I went on later that day to find more trout at similar locations. Maybe this article satiated your curiosity. Perhaps it will help you in your fishing endeavors and you will Fish Smarter!

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About the Author Captain Devin

Devin is a Marine veteran of the Iraq War, entrepreneur and a hardcore inshore angler who enjoys chasing limits of specks and sight fishing redfish.

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