Salmon lure seeing is the art of grabbing the attention of a trophy king or silver through its sense of sight. A fish’s sense of sight is integral to its bait biting processes. That is why it is so important to think about what do fish see. Appealing to a salmon’s visual sense is essential enough that sight earned a spot on the Bait Set-up Triangle. Our blog this month explores salmon fishing through the science of underwater light and vision.
The first thing to address when asking what do fish see is that seeing things underwater is not the same as seeing things above water. There are similarities between how the human and fish eye works, however. If you are not thinking about how your salmon lure looks from an underwater perspective, you should definitely ask yourself, “What do fish see?”
Light’s pathway is different underwater than what we are used to above the water’s surface. For a salmon to see your lure light must penetrate the water’s surface, hit your bait, bounce off your lure, hit the salmon’s eye, move through the eye, hit the eye’s light-sensing cells, and register an image in the salmon’s vision brain center.
Underwater Lighting
First, not all light above the water’s surface passes through. We have all experienced a sun-burned face from a day on the water, even though we’re wearing a hat. This is because a bunch of light bounces off the water’s surface and toasts our skin. Bounced light means less light under the water’s surface, lighting up your lure.
Second, the light energy that penetrates the surface runs into light scattering stuff as it moves down into the depths. Light scattering stuff might be an algae bloom or sentiment from a nearby river. The important part here is that it further reduces light energy the deeper you go. Go deep enough, and it is zero. Also, light’s longer wavelengths are removed near the top, and the shorter wavelengths go deeper. Red light does not penetrate as deeply as blue light due to its wavelength. Light scattering also impacts how an image looks. If you are far enough away from an object, it may disappear altogether due to this effect.
Third, light that bounces off a lure radiating out to the side has much less energy still. One science report says that side-bounced light loses more than 90% of its radiant energy underwater. Less light energy bounced off your lure means a salmon needs to be closer rather than farther away to see your bait.
What do Fish See in Varying Circ*mstances:
We set out to illustrate how downwelling light might make your lure look to your trophy salmon. We set up a simple light studio and took pictures of a lure setup. The studio was a floodlight placed on top of a five-foot piece of four-inch drain pipe. Then a hoochie rigging was tied between two chairs. The drain pipe worked pretty well in turning floodlight illumination to underwater downwelling light. Also, we colored clear pieces of acetate with a sky blue permanent marker to simulate water in our experiment determining what do fish see.
Figure 1 is with the camera above the hoochie. The colors realistically represent the hoochie’s colors as seen by the human eye, and the skirt details are sharp.
Figure 2 is a side view image minus any “underwater” filters. Notice the white background becomes gray in downwelling light and the light seems to pass through making colors glow a bit.
Figure 3 is a side view image with one “underwater” filter between the camera lens and the hoochie. The filter simulates water that scatters light. The result is that once sharp lure outlines begin to lose their detail.
Figure 4 is a side view image with four “underwater” filters between the hoochie and the camera lens. The four filters attempt to simulate more distance and water between the fish’s eye and your lure. Notice that the gray background seen in Figure 2 is gone. The skirt details are further diminished, and the lure is less visible.
Figure 5 is a bottom view whereby the camera is underneath the lure and looking up into the downwelling light. Given the size of the camera and the haste in making the photo studio, there was not much distance between the lens and the hoochie. So, the image is a closeup of a part of the lure. Nonetheless, the image still shows the hoochie is more silhouette than rich blue and green colors, as shown in Figure 1.
From last month’s blog, Saltwater Fishing Tackle Innovations, many salmon seem to attack from below your bait. The silhouette view is an important perspective to keep in mind.
When you think like a fish:
The final thought is that water conditions, light, and distance between your trophy and your lure affect how salmon see your bait. At times fish won’t see your bait unless they are very close. The use of scents counters this issue for fishing enthusiasts. One scientist commented that scent is the distant lure since compounds remain in the water column and reach further than sight and sound. To combat lighting issues add scent and catch salmon!
Have you tried our DBS-Striker Formula for your fishing scent needs?
