Beyond the Bite: Using Sonar to Measure Fish Curiousity vs Committment

The purpose of this project is to determine if lure color influences the predatory behavior of lake trout (Salvelinus namaycush) in the Yukon. I was inspired to conduct this experiment as ice fishing is my favorite winter activity and I want to catch more fish and more often. By using sonar technology and a controlled testing rotation, I aim to find out which color attracts the most lake trout and triggers them to bite the lure. My experiment will test if glow in the dark jigs work better than normal colors. This experiment is important because may people ice fish for lake trout in the Yukon. Due to low light conditions and cold water temperatures, lake trout are less active during the winter and this makes color choice of lures more important compared to the summer.

Using a sonar will allow me to keep track of how each lake trout observed reacts to the different colored jigs instead of just testing which color is lucky. The sonar also allows me to keep track of how each fish reacts to the jigs because this sonar sees a large area under the ice fishing hole that you can watch real time. When fishing without it, you can’t know if you are not catching any fish because they are not there or if they don’t like the jig. My project can benefit other people who like ice fishing and increase the chances of a successful ice fishing trip.

My Dad and I went ice fishing on Kluane Lake, Kathleen Lake, Atlin Lake and Lake Laberge in the Yukon between January 31 and February 7, 2026. To test which of the four test jig colors worked best compared to the white control, we ice fished in 15 minute segments and changed the lure after each segment. One person was the test fisher and changed jigs every 15 minutes and the other person was the control fisher and used the white control jig for the whole hour. After the hour, the test fisher and the control fisher switched. We fished for 4 to 6 hours on each lake for a total of 18 hours on all of the lakes combined.

I used a Livescope sonar (Garmin LVS34 transducer with echomap 95 sv plotter/screen) to record how each lake trout observed reacted to the jigs during each 15 minute segment. I recorded each lake trout as one of these and added up points on how they reacted. I then added up the points for each jig on each lake. For the white jig, I divided the total points by four because it was used four times as long as the other jigs.

Was curious about the jig – 1 point

Chased the jig – 2 points

Bit the jig – 3 points

I also calculated a bite conversion to find out how many of the lake trout that looked at the jig ended up biting. To do this, I divided the number of bites by the total number that looked at each jig. I kept track of all the lake trout we caught with the jig that they were caught on and how long each fish was.

All of the jigs used attracted lake trout on all the lakes I fished. The white jig with the red head attracted the most fish compared to all of the other jigs and the glow with an orange head attracted the fewest (see Figure 1). I think this was the best jig because in deeper water the red looks black and this makes the lake trout think it looks like a real fish to eat. Many prey fish that the lake trout eat have a slightly darker head as compared to their body and this jig mimics this color contrast at depth.

There were differences in all of the lakes but the white with red head jig was one of the best jigs in all lakes except Kluane Lake (see Figure 2 to 5). The reason for this is unclear but it could have been due to random chance. I observed on Kluane Lake that the fish were not even during the fishing time and they often came by in groups which made it harder to determine which jig was best on this lake.

Across all lakes I fished, we saw 62 lake trout on the Livescope:

Kluane Lake – 8 fish observed in 5 hours – 1.6 fish per hour

Kathleen Lake – 16 fish observed in 4 hours – 4.0 fish per hour

Atlin Lake – 20 fish observed in 4 hours – 5.0 fish per hour

Lake Laberge – 18 fish observed in 5 hours – 3.6 fish per hour

During my research I learned that colors such as red fade out at a shallow depth, white at an intermediate and blue-green at the greatest depth. It is possible that the white jig with a red head attracted many more fish on Kathleen Lake because this lake is extremely clear - it is possible to see yoru jig under the ice at more than 60 ft ! This jig likely looked very similar at depth compared to the surface but in the less clear lakes I fished, the colors may have washed out and therefore been less effective.

The bite conversion data is the primary conclusion from my results as it indicates which jig recieved the most bites by fish during my experiment. The blue jig had the highest bite covnersion rate across all lakes combined – Figure 6. This means that more fish that looked at the blue jig bit this jig. White and white with a red head were second and almost the same. The glow/green and glow/orange read got zero bites on all of the lakes I fished. I think more fish bit the blue jig because its color looks more natural under the water and the darker color has more contrast.

We had 17 bites during all of the ice fishing we did. Some of these we didn’t get hooked or lost them before we could get them through the hole. We were able to get 6 lake trout through the hole to measure them - Table 1. The smallest lake trout was 59 cm and the largest was 92 cm. Most of lake trout we got through the hole were on the white control jig, maybe because this jig has an extra hook on it.

The relatively low bite conversion rate was an important learning from my project which was possible to learn because of the forward facing sonar I used. This really showed that lake trout often investigate your jig without biting and most anglers would not even know this is happening if they don't have a sonar !

If I did this experiment again, there are a number of things that I would do differently:

I would test other colors like pearl or purple color which looks more natural. Solid black would also be good to test gives even more contrast in the water compared to the colours I tested. A clear jig would also be good to test and might be a better control that the white jig that I used.

I would like to test other kinds of lures (such as spoons, bucktails, or other jigs) or test the effect of using different scent attractions.

My Dad Ben Schonewille was my mentor for this project, took me fishing (and paid for the gas) and helped me with the study design, data analyis and computer work including this project board. He also helped me research the project and used his fish biology knowledge for this. My Dad's work (EDI Environmental Dynamics Inc.) let me borrow a Livescope sonar to collect my data while ice fishing. Christinna Tennant made me a map of the lakes where I collected my data. Shannon Jenner helped me with the layout and printing of my project backdrop. Whitehorse based photographer Peter Mather (https://petermather.com/) let me use some of his scenery photos for this project board. Thank you to everyone who helped me with my project !

Journal articles:

Bunnell, D. B., Ludsin, S. A., Knight, R. L., Rudstam, L. G., Williamson, C. E., Höök, T. O., et al. (2021). Consequences of changing water clarity on the fish and fisheries of the Laurentian Great Lakes. Canadian Journal of Fisheries and Aquatic Sciences, 78(10), 1524–1542.

Harrington, K. A., Hrabik, T. R., & Mensinger, A. F. (2015). Visual Sensitivity of Deepwater Fishes in Lake Superior. PLOS ONE, 10(2), e0116173.

Keyler, T. D., Hrabik, T. R., Austin, C. L., Gorman, O. T., & Mensinger, A. F. (2015). Foraging mechanisms of siscowet lake trout (Salvelinus namaycush siscowet) on pelagic prey. Journal of Great Lakes Research, 41(4), 1162–1171.

Reports:

Government of Yukon. 2023. Lake Trout and Lake Whitefish Monitoring Program: 2021 Program Update (SR-23-07). Government of Yukon, Whitehorse, Yukon, Canada.

Books:

Scott, W.B. and Crossman, E.J. 1998. Freshwater Fishes of Canada. Galt House Publications Ltd., Oakville, Ontario.

Images:

Inland Fisherman Magazine (2026). Graphic of colour penetration underwater.  https://islandfishermanmagazine.com/choosing-the-right-colour-lure/

Webpages:

Choosing the Right Colour Lure. Inland Fisherman Magazine. Retrieved April 29, 2026 - https://islandfishermanmagazine.com/choosing-the-right-colour-lure/