By Jason Mitchell

I have often felt that it is much easier to learn a lake during the open water period. Structure and bottom contours can be broke down quickly when using a boat equipped with good sonar and GPS. Often during the winter (just like during the open water period) the sweet spots that attract fish are often subtle. Subtle changes like openings and lanes in weed beds, changes in bottom composition where the basin transitions to sand or gravel, rock piles where larger rocks form inside turns and fingers… the details make the difference for dialing into fish locations all year long.

Now these small details can be dialed into once there is ice but these spots can be discovered and saved much easier with a boat months before the lake freezes. I find myself relying on these open water recon efforts more and more each season. GPS mapping and detailed contour maps found on map chips have been a huge aid for learning water quickly regardless of time of year. Remember however that these spots, this information is available to anybody with a hundred dollar bill. Humps, sunken islands and points that used to sit deserted all winter now often have anglers because more and more anglers are utilizing this technology. The key now is learning the spots in more detail, becoming more intimate with the structure that is revealed on the map chips and most of all, finding spots that hold fish that won't show up on a chip.

Changes in bottom composition won't generally show up on most contour maps or map chips. Subtle bumps and depressions on flats are also often lost. Depressions found on flats are probably one of the most productive structural elements an angler can look for when attempting to find fish running large basins. Small depressions or pockets often seem to funnel fish. Small depressions or pockets in shallow weedy flats are also usually good if fish are in the area. These subtle depressions often don't show up on a chip in detail because the change in depth is often subtle, a foot or less.

Transition areas where silt or muck transitions to gravel or sand are also key areas particularly for walleye and pike. The best sonar I have ever used for determining bottom content is the Vexilar Edge LC507. By turning up the range, I can look for second and third echoes which indicate a harder bottom. These transitions are than saved as icons or waypoints on my GPS.

Like many anglers, I use different icon and GPS symbols to indicate different things. I might use one specific color of diamond to indicate the actual weed bed and use another color to indicate openings, lanes or edges so that I can essentially map out the weed bed. I use one particular symbol to mark the top of the rock pile or hump and use a different symbol to mark a sweet spot on the deep edge where fish have been caught, etc. I than try and make a point to keep this information organized and logged so that when the ice covers the lake, I am ready and can quickly hit key spots without wasting any more time than necessary.

Catching more fish through the ice always boils down to fundamentals and efficiency. This information allows me to fish through an area and determine that fish aren't on the spot quickly which is crucial so that I can be on the move to the next location. Hitting the general bull's eye isn't necessarily good enough, a much better strategy is to have a detailed picture of the spot in your head and be able to hit the key "spot on the spot" locations effectively by using GPS. By incorporating this information, I waste fewer minutes fishing areas that are generally much less productive.

Now obviously this strategy of open water research isn't possible when traveling to new bodies of water and we often find ourselves hitting new lakes each winter chasing hot bites. For home water however that you know you will be spending a significant amount of time on come winter, you will be amazed at how many more fish you will catch by spending time in your boat getting a better understanding of the structure you will be fishing. As a guide for the Perch Patrol on Devils Lake, the information I can gather over the summer is crucial for my success during the winter.

Editors Note: The author, Jason Mitchell earned a reputation as one of the region's top ice fishing guides spending most of his career on North Dakota's Devils Lake (Perch Patrol Guide Service). Mitchell also manufactures and designs a series of extremely high quality, application-specific ice fishing rods that bear his name, the Jason Mitchell Elite Series Ice Fishing Rods ( Mitchell also hosts the outdoor television show, Jason Mitchell Outdoors airing on Fox Sports North and is credited for pioneering many of today's advanced ice fishing concepts and tactics.