Reverse course to find more fish using Humminbird Side Imaging
Locating the fish you're looking for can often be easier if you change your boat's direction of travel
Humminbird Side Imaging is an incredibly powerful tool for identifying both structure AND fish. I rely on Side Imaging and 360 Imaging to the extent that, if I don't see fish beneath or around the boat, I will only rarely stop to try to catch fish from that apparently empty water. There are certain circumstances, however, in which fish are difficult to identify as they disperse around the boat. These fish can be well within the useful range of Side Imaging or 360 Imaging, but because of the local bottom composition, those fish may be difficult to visualize. This article is devoted to one such set of circumstances, when fish are relating to a transition between hard bottom (rocks) and soft bottom (silt or muck). First, consider the screen capture from my Humminbird 1198 below:
This screen capture was collected while traveling west along a heavily rip-rapped shoreline. The shoreline flat is shown in red on the right hand side of the screen capture, with the shoreline highlighted by using the "Shallow Water Highlight" feature of my LakeMaster chip. The individual rocks of the rip-rap shoreline and extending onto the shallow flat are quite recognizable on the left side of the Side Image view. The overall bottom is bright in color, consistent with a very hard bottom. Rounded shapes from rocks are easy to identify. At the base of the rocks, the bottom transitions to very soft silt or muck, as indicated by the much darker images of the bottom that extend to the right edge of the Side Imaging view. There are LARGE numbers of fish relating to the distinct edge separating the hard bottom shoreline flat and drop-off, and the soft bottom associated with the near-shore deeper water. Can you see them?
Don't worry, I can't see them either.
When fish are relating to hard bottom, the bright white signals that we typically associate with fish become very difficult to see against the bright signals associated with the hard bottom. Fish can often be identified by observing their sonar shadows, but depending on the precise nature of the bottom, even those shadows can be masked by bottom irregularities. With many rocks on the bottom in this area, the sonar shadows from the small and large rocks are mixed with sonar shadows from the fish, making the fish "invisible".
But they are there!
How did I find the fish relating to this shard hard/soft bottom transition? I reversed course. I turned the boat around and drove along the transition on the hard-bottom side, rather than the soft bottom side. This caused the sonar signals associated with the fish to stick out like sore thumbs, because they were now imaged against the soft, silty bottom rather than having a hard, rocky bottom as the backdrop. Likewise, because the soft bottom doesn't have the irregularities of the rocky flat, the many (MANY!) sonar shadows of the fish are just as easy to see.
Check out the screen capture below. This is the same area as above, just imaged from the opposite direction. Can you see the fish now? I sure can!
So, we've found the fish. What were they? Crappies. Nice ones. A picture of some of them are at the top of this page. Fall is my favorite time to fish crappies on large rivers. They are relatively unpressured by most anglers in the Northland, they are easy to predict and pattern, and they are exceptionally willing to bite under nearly all weather conditions. They have saved MANY trips for me and my guests. Nothing beats a big crappie in the fall, and no tool is more valuable than Humminbird Side Imaging for finding them.