Category: Learn to Fish Series

Different species of fish prefer different water temperatures. The fish you have access to in your local stream or river will depend on the temperature and cover – and even though many warmwater fish can survive over a wider range of temperatures than coldwater fish, there are still ideal conditions for the species you are hunting.

How can I quickly & accurately test water temps?

Testing the water temperature when you’re fishing is a good idea in general, and one of the tools that I usually take with me is a Deeper Pro+ Sonar. There are multiple models available at different price points.

The added benefit is that you can tie this unit to your fishing line and cast it to inspect the opposite shoreline, deep holes or underwater structure. (Personally, I use mine to create useful topographic maps when I am fishing from the jon boat, and occasionally when fishing from shore. The maps are great for reviewing after I get back from a trip to learn even more about the area.)

Preference by Species

Most anglers know that trout need cold water, and largemouth bass prefer warmer water, but what they don’t realize is that there are considerable differences in preference even among warmwater fish. The chart below shows the preferred temperature ranges of common warmwater species – notice that the range covered is more than 30 degrees.

Even though many warmwater fish CAN survive over a wider range of of temperatures than coldwater fish, there is still an ideal temperature range required for every species to thrive. For example, a warmwater fish could survive in a trout stream, but the water temps would be too low for optimal feeding and growth, making it difficult to compete with the trout or grow to the size we’d like to catch.

The temperature of a stream depends mainly on it’s primary source of water. To support a diverse population of fish, additional springflow is usually necessary. Springflow helps the water stay cooler in the summer, and warmer in the winter (preventing freezing, and allowing fish to feed throughout winter instead of going dormant).

Other factors like shade, the course of the stream, the shape of the channel and the gradient of the streambed all impact the temperature as well. Different sections of the same stream can be different temperatures. For example, a shaded stream can run 5 to 10 degrees cooler than a similar stream in direct sunlight. A shaded run can also be several degrees cooler than an unshaded run in the same stream.

Water in narrow, deep channels tends to stay cooler than water in wide, shallow channels because less of the water comes into contact with the air.

Some streams or rivers also contain lakes along their course. Some are natural, others are the result of a dam. In either case, the stream temperature below a lake will be several degrees warmer than the stream temperature above the lake (unless the lake has a coldwater draw, which we will talk about in the next section in this series). The lake water may also stratify into different layers, however this does not happen in streams or rivers – the water stays turbulent and completely mixed – which means the surface temperature is darn close to the temperature right above the streambed (unless the water is very deep).

Water Temperature by Species Chart

Information provided courtesy of: The Freshwater Angler™: Fishing Rivers & Streams.

Species	Temperature Range
Redbreast Sunfish	80° to 84° Fahrenheit
Flathead Catfish	78° to 82° Fahrenheit
Blue Catfish	77° to 82° Fahrenheit
Channel Catfish	75° to 80° Fahrenheit
Bluegill	75° to 80° Fahrenheit
Spotted Bass	73° to 77° Fahrenheit
Redear Sunfish	73° to 77° Fahrenheit
Black & White Crappies	70° to 75° Fahrenheit
Largemouth Bass	68° to 78° Fahrenheit
Muskie	67° to 72° Fahrenheit
Smallmouth Bass	67° to 71° Fahrenheit
Striped Bass	65° to 75° Fahrenheit
White Bass	65° to 75° Fahrenheit
Walleye	65° to 75° Fahrenheit
Northern Pike (under 7 lbs)	65° to 70° Fahrenheit
Northern Pike (over 7 lbs)	50° to 55° Fahrenheit
White Sturgeon	65° to 70° Fahrenheit
Wiper	64° to 66° Fahrenheit
Sauger	62° to 72° Fahrenheit
Shad	60° to 65° Fahrenheit

Moving Forward

Now that we know what species typically prefer what water temperatures, we’re going to look into some other factors that can impact the overall temperature of a stream or river. This is yet another piece of the puzzle that we are putting together to get ready for some new exploration this coming year.

Onward my friends – tight lines!

NEXT SECTION: Changing Temperatures in Rivers & Streams
PREVIOUS SECTION: Cover & Current Breaks [Part 2]

[ Back to the Index Page for Learn How To Fish Rivers & Streams ]

Now that we have gone over some of the different kinds of cover, where the most cover can be found, and areas that fish consider to be prime real estate – fish magnets – let’s look at some visual examples so that we have a better idea of what to actually look for when fishing a river or stream.

All of these images have been scanned and taken from an awesome reference titled The Freshwater Angler™: Fishing Rivers & Streams. I’m not going to place the photo link / credit after every picture because there will be quite a few – but make sure to try to get a copy of this book. (My grandpa gave this copy to me and it’s nice to have!)

We’ll start with a definition of a word that gets thrown around a lot…

What is an “Eddy” in a river or stream?

An eddy is an area in a river or stream where the water actually flows against the main current. This is the result of something disrupting the main current flow, like shoreline that extends into the channel, or a rock or log. Eddies typically form on the lower side of the obstruction, but they can also form on the side facing into the current, and in either case they usually create some sort of slack-water area.

How to Identify Eddies & Slack-Water Areas

Additional Overhead Cover to Look For

Remember that the best spots to hide not only include slack-water – but overhead cover as well – these areas are especially attractive to larger fish!

Again, all images provided by this great reference that I strongly suggest you get a copy of: The Freshwater Angler™: Fishing Rivers & Streams.

Moving Forward

Next, we’ll take a look at what species of fish prefer what water temperatures. We’ll also discuss what can cause that temperature to change in rivers & streams. This will come in handy as we start to explore new water this year – so make sure to stay tuned for those videos as we report on both success and failure.

Progress, progress, progress. Tight lines!

NEXT SECTION: Preferred Temperature Ranges of Warmwater Gamefish
PREVIOUS SECTION: Cover & Current Breaks [Part 1]

[ Back to the Index Page for Learn How To Fish Rivers & Streams ]

Now that we have looked into current and the affect it has on the fish in a river system or stream, we should go a step further and discuss cover and current breaks. We’ll do this in two phases, starting with some basic concepts provided in: The Freshwater Angler™: Fishing Rivers & Streams:

If you think about it, it’s natural that fish living in current would seek out anything that might prevent them from being swept away. The moment they hatch new fry are small, weak swimmers – and food for larger predators – but fortunately, they can find cover and concealment behind pebbles and gravel… to start.

As fish grow, they will need to find larger types of cover to both shade and hide themselves. It is common for the largest fish in a system to set up near the largest boulders, or near logs or banks with the deepest undercuts. Streams & rivers without cover like this will probably not hold as many large fish.

In the previous article we discussed the different species of fish found in currents of varying strength and their general tolerance to that current. Fish like smallmouth bass have a higher tolerance and so in an area with more current, a single boulder or even a branch can provide enough cover to hold a quality fish – but crappie and largemouth (fish that prefer slower current like what we could expect in a pool or low-gradient area) would probably require more substantial cover to block faster current enough to hold in that stretch of water.

Streams that wind and meander typically have more structure, cuts and cover than those that are straight. Remember too that smaller streams make it easier to see the pool-riffle-run pattern that changes the bottom composition and strength of the current, as the same amount of water has to move through narrow and wide areas – ultimately leading to many deep holes and undercut banks. Straight streams can be more uniform, and therefore offer less cover, meaning fewer adult fish will be present.

The best cover will not only offer a break in the current, but provide overhead protection (from the sun and predators) as well. This means that fish may well prefer the slack water of an undercut bank to say, slack water behind a boulder. The undercut bank offers more robust protection – but both can hold fish.

Whether you are fishing a lake or a stream, most bodies of water have some prime real estate. Areas of cover (either visible or submerged) that are just “fish magnets”. A good spot is a good spot, and when the largest and most dominant fish that set up in these areas are caught, they will either return upon release, or another fish of similar size will move into the area. Pay attention to areas that are productive and revisit them to test this concept.

Over time you will start to recognize visual cues that mean there is cover present. At first, you will miss many of these spots – but that’s good for two reasons. First, other less experienced fishermen will miss them as well, and second, the more you practice, the more cover you will be able to identify, and the more cover you can identify, the more fish you will catch as you continue to develop as an angler.

Moving Forward

Now that we know more about cover and current breaks in a river or stream – and why they are important – let’s go ahead and put together a list of common slack-water areas that you can look for which may very well hold gamefish.

The combination of these concepts & targets will help us zero in on success.

Tight lines!

NEXT SECTION: Cover & Current Breaks [Part 2]
PREVIOUS SECTION: What is Current in a Body of Water?

[ Back to the Index Page for Learn How To Fish Rivers & Streams ]

Recently, we discussed what a channel within a river or stream is and where it is located. This knowledge will help you find the deepest, fastest water without the aid of electronics. But are there other factors that come into play and impact how fast your body of water is moving?

Yes.

Does the speed of the current help determine what fish are present as well?

Yes.

Let’s take a look at what can increase or decrease current speed, and how fish behave in these different conditions.

What is current?

A current in a river or stream is the flow of water primarily influenced by gravity as the water moves downhill. Over time, this flow can lose its potential energy. The rate of movement, speed and direction are all important factors.

Current is the force of flowing water, typically discussed in terms of “speed”. This speed is usually determined by the slope – or gradient – of the streambed, the shape of the channel, and the amount of flow.

A high-gradient stream is one that drops rapidly in elevation. One that slopes slowly would be considered low-gradient. A stream can also contain both high and low gradient areas. The gradient is typically highest near the source, and it slows as it flows along, especially as sediment is deposited (this gradually flattens the streambed, slowing current). Usually the slowest current speed can be found near the mouth, where the flowing water enters another body of water. (Note that in some cases the water flow will slow and spread before connecting with another body of water, simply soaking into the ground.)

If the flow increases, the current will generally increase as well. A narrow passage or shallow area can also increase current, because the same amount of water is forced through a smaller area.

What are pools, riffles & runs?

When the current increases, it can excavate a deep pool. In this pool, the current is much slower and the sediment carried here settles out. As the sediment builds up though, it can cause the water to get shallower – and remember when water gets shallower it causes the current to speed up because the same amount of water is forced through a smaller area – this increased current is called a riffle. Riffles are shallower, faster moving areas of a stream, and their fast water starts to dig the channel deeper, creating a run. This run is usually characterized with a more moderate current and it will continue until reaching the next pool where the process repeats.

This is what leads to the typical pool-riffle-run configuration, which is very noticeable in smaller streams, but can be harder to identify in larger bodies of water.

Pools also look calmer on top, because the sediment that settles in the slow current consists of fine materials: sand, silt or muck. In riffles and runs where the water moves faster, sediment washes away and the gravel, rocks and boulders that remain can deflect the current and produce more turbulent waters.

How does current impact fish behavior?

Fish behave differently in fast current versus slower current. For example, fish in faster water are conditioned to grab food quickly without much examination. If they didn’t the current would simply sweep their meal away! This means that fish in faster water are quicker to hit a lure when compared to those in slower water. Fish are also easier to locate as they are typically confined to slack water areas where they can avoid fast current – as opposed to being scattered all throughout an area.

The deepest, fastest water always follows the outside bends along a channel, and expert stream fishermen can quickly spot these deep zones at a glance. They also know that most stream species hang out in or alongside these areas.

If you are targeting a specific species of fish, it helps to know which fish prefer high-gradient areas, medium-gradient areas and low-gradient areas. Let’s take another peek at one of our references: The Freshwater Angler™: Fishing Rivers & Streams:

High-Gradient areas are favored by species like smallmouth bass and steelhead. The higher the gradient, the more the fish hug the bottom to escape the current. These areas typically hold the largest rocks and boulders.

Medium-Gradient areas are favored by everything from walleye to channel catfish, sauger, muskie, spotted bass, sturgeon, striped bass, wipers and shad. These areas have a more moderate current which means the fish don’t have to hug the bottom quite as tight, and there are usually fewer boulders but a good mix of rocks and gravel.

Low-Gradient areas are favored by largemouth bass, pike, blue & flathead catfish, white & black crappie, bluegill and redear sunfish. The slower current means silt and muck can settle, resulting in a smooth streambed and fish cruising further off the bottom.

* These “speeds” are relative. There are usually no fish found in the absolute fastest water.

Moving Forward

Next, we’ll spend a little time discussing cover and current breaks. If you need a refresher, make sure to bounce back to review what a channel is – all of this knowledge we are amassing is important as we get ready to explore new streams and rivers this coming year!

Last year we had good luck in small lakes… this year, we have our work cut out for us.

Let’s keep making progress. Tight lines!

NEXT SECTION: Cover & Current Breaks [Part 1]
PREVIOUS SECTION: What is a Channel & Where is it Located?

[ Back to the Index Page for Learn How To Fish Rivers & Streams ]

To the angler that does most of their fishing in lakes and reservoirs, approaching streams and rivers can seem quite foreign. (I’m speaking as someone who is currently intimidated by these winding bodies of rolling water.) The fish behave differently, they use different locations, respond to different presentations, conditions can change constantly… things are just… well, different.

However, a 30 second internet search will reveal the truth: there are many stream & river fishing opportunities that we are missing.

Question is… how do we fix that? Where do we start?

Answer?

Right here, right now.

Let’s discuss what a channel is, and where the deepest water in a river or stream is typically located.

What is a channel?

A channel is typically a narrow, fluid body of moving shallow water that provides a path for sediment flowing within the stream (or river) banks. Vegetation, sediment load, slope and flow can lead to constant changes that affect both aquatic & terrestrial life.

Because the water is moving, the fish in these areas can be slightly more resilient to changing weather conditions like cold fronts, cloud cover and changes in air temperature. If you have the option to fish either a small lake or a stream after a cold front – it might be a good idea to pick the stream!

It is also important to note that many sources seem to refer to the channel as something that is actually within the stream or river itself. The channel is part of a river or stream. Look back at our definition above, the channel provides “a path… flowing within the stream (or river) banks”.

Where is the channel actually located?

Next, it’s important that we understand the general underwater makeup of these channels, especially since most of us will not have access to our depth finders or the electronics we’re used to relying on when we’re fishing lakes. To understand where the channel itself is located (along with the deepest water) let’s look at a cross-section provided by The Freshwater Angler™: Fishing Rivers & Streams:

In a straight section of a river / stream?

Along an outside bend of a river / stream?

Along an inside bend of a river / stream?

Moving Forward

Next, we’re going to talk more about current, current speed, and the different elements that factor into this attribute in your body of water. This is important knowledge to have, especially if you’re like me and plan to hike & explore as many streams as you can find in the near future!

That’s a big goal for this year.

Last year, it was important to take some bad habits and turn them into good behaviors. These behaviors resulted in a whole bunch of awesome fish – now this year, it’s time to repeat that process and catch more fish from more bodies of water.

Let’s keep pushing ahead. Tight lines!

NEXT SECTION: Understanding Current and How it Affects Fish Behavior

[ Back to the Index Page for Learn How To Fish Rivers & Streams ]