Thermography from the Air
2011 May 06
Deciding where to target bass on a large body of water is a bit of a daunting task. The old saying of “80% of the bass are in 20% of the water” is a fairly accurate statement, personally I feel it’s more like 90/10 lately. Fortunately there are tools at our disposal to make these large bodies of water ‘smaller’. These tools include Google Earth, sediment charts, DrDepth charts, high speed bass boats, SideScan sonar, and thermal imaging – otherwise known as Thermography.
It is pretty much a given that if you can find the warmer water you will find the fish. The biggest problem with measuring water temperature with our fishfinders, is that we are looking at surface temperature, and therefore have no idea what is happening just a few feet under the surface. Then we run into a host of problems with area covered and data capture for comparison, giving us a very limited thermal knowledge of our surroundings.
Aerial Thermography however is the quickest and most accurate method of collecting reliable data for temperature comparison. This exercise is carried out using a thermal imager with a relatively fast refresh rate.
The aerial survey is best carried out with a small plane or helicopter with the door removed for easy movement of the camera.
This exercise is to be carried out at first light, BEFORE the sun has had a chance to start warming the water surface. The other reason for doing this at first light is that the warmer water below the surface has had a chance to well up over night thus influencing the surface temperature significantly.
This little overgrown cove is clearly holding some war water. The other interesting thing to note here is how the warm water is feeding into the shore below it, but not above it. So the first area you would target here is the little cove, and then along the shoreline below it.
This bay has a vertical rocky face in area 1, and is holding some very warm water right on the shoreline, so this would be my first choice. The second spot to run to would be the little cove on the bottom right, with the last spot for this area being right in the back of the bay on the right hand side bank.
This is also a very interesting spot because you can see how the two coves have cooled down substantially over night, but the main river channel is still holding warm water very close to the points on these coves.