From the March 2011 issue of Susquehanna Fishing Magazine:
http://susquehannafishing.com/
By William Milheim
I spend my spring, summer, and fall on the North Branch. Every week or so the Rod Gods smile on my boat and give me that one hundred fish day. When no matter what you throw at them, they hit. As you can guess, I love those days. Many elements need to come together for those days to happen. Last month we discussed weather and the part it plays for a good day of fishing. This article will focus on water temperature and how it affects the bite.
For this discussion my target fish will be smallmouth bass. Water temperature is a good element to understand, as it relates to smallmouth. For the most part, water temperature will give you a good idea where and how to fish.
Before we get started, it helps to know a few differences between lakes and rivers when it comes to water temperature. Lakes have water surface temperature, bottom temperature, and a thermocline in between. Rivers are far easier, because there isn’t any difference between the surface temp and the bottom temperature, and that’s a fact. Because the river is flowing and constantly in movement, most of the time there is less than one degree difference.
We’ll start right after ice out. On the North Branch it can very from mid March to mid April, it depends. Usually I start after the fear of running into a large chunk of ice is over. The water temperature is in the high thirties. Smallmouths are still in deeper water. Fishing during this stage is fun, but locating them can be difficult, but once you find them the fun starts. Some big fish can be caught at this time, but I cannot stress enough that your presentation needs to be slow. The fish are very lethargic and don’t offer a hard fight.
Once the water warms to the mid forties, pre spawn will begin. This is a great time to be a fisherman. Smallmouth will stage near the shallow water and start to fatten up for the spawn. Some years the water temperature will hover around forty eight to fifty two degree range for a few weeks. That’s good times... When the water starts to warm up to the mid fifties, the catching will increase. Smallmouth move into five feet and shallower to start selecting spawning sites.
Somewhere around sixty degrees spawn will start; fish will be shallow, on out to five to ten feet. Most spawning activity ends once the water warms up to the higher sixties to seventy degrees. Fish will start to move into deeper water to recover from the riggers of spawning.
Take note that from ice out to the seventy degree range, smallmouth tend to be in shallow water. Less than a foot of water at the river’s edge the water will be warmer this time of year. It will hold a lot of baitfish.
From ice out to mid sixty degrees, smallmouth are not hard to find in the river, and are easy to catch. Now, when the water has warmed to the seventies and the smallmouth are not where they were in the spring, it’s the summer slow down. Water temperatures continue to climb; this is when I see fishermen going to deeper water with little or no success. We know now that deep water doesn’t mean cold water in the river.
In summer when water temperature rises to seventy and above things are changing. From ice out to this point, water is clear and carrying plenty of dissolved oxygen. Now all of the plants and algae start to grow. Most water now doesn’t contain enough oxygen to maintain a smallmouth. In the summer you must concentrate on moving water where abundant oxygen is there for smallmouth.
As summer comes to a close, again we need to consider water temperature. Just because the calendar indicates its fall, it doesn’t mean the fall bite is in play. I spoke to a gentleman that took off work to fish the fall bite and the river wasn’t close to that time yet. All of the vegetation that grew during warm water conditions now needs to stop growing and die. This starts when the water temperature dips under sixty for a period of time. During this time we still need to focus on moving water, because dieing vegetation requires oxygen to rot. Once the temperature hits the mid fifties the fall bite will start. This past fall (2010) the fall bite started very late. It lasted till mid November when the water slipped under forty degrees.
It is interesting how water temperature affects smallmouth. Experts say the optimal water temperature for smallmouth is from fifty five to seventy degrees. Smallmouth will feel distress when the water temperature rises to eighty six degrees and will die off at ninety degrees. This summer I noted a water temp of eighty five degrees. On the colder side, smallmouth will be in distress when water temp drops below thirty four degrees and die off below thirty two degrees.
Whatever your target fish is in the river, all are on a water temperature schedule. Learning a little more on how fish react to water temperature will definitely help in your success.
Now that we are aware of how weather and water temperature affect our day on the river, in the next issue we will discuss how dissolved oxygen plays a huge factor for most of the fishing season.
Bill Milheim has been fishing and guiding the North Brach of the Susquehanna River for over 25 years.
