When the water temperatures fall to the mid 30's in shallow bays, pan fish can be very difficult to catch. The combination of noise from vehicles, ice augers, shacks and anglers can easily make fish spooky while the cold water temperatures virtually shut down these cold blooded fish. For many people it is called the "Mid Winter Lull". Do not fret however because the fish do continue to bite aggressively, just perhaps where you are not.
Warm water temperatures are key during mid-winter and the easiest way to find warm water is to go deep. In fall, the water cools from the top down verse the opposite in spring warming. This means that the deeper you go, the warmer the water is. I personally love fishing deep this time of year but it too can be difficult. Let me tell you a few ways I catch these fish.
When fish move deep they seldom relate to structure like the fish you find in shallow weed beds or stump fields. This means that the fish are constantly on the move searching for food. Because of this you must move with them. The only way to be successful is by using lightweight augers and electronics like Guide Series GSX flashers of GSVS Underwater Cameras. Once you have located the fish you must attack quickly because remember, these fish are moving. My finding them after they have moved by drilling more holes, you can at times get a general idea of which direction they are heading. Now its time to chase them with lures.
I love to use the lightest line I can and Power Pro's Ice Line allows me to use fine diameter lines that sink fast and have the no stretch qualities that allow me to feel the subtle bites that these panfish create even in depths exceeding 20 feet of water. Second it is important to use heavy jigs. Jigs now can be found made of materials like traditional lead or new and popular tungsten. If it is an ultra light presentation that the fish prefer, I will go to a dropper weight like a sinker or small spoon.
Once you get down to the fish quickly, it is important to catch as many as you can before they move on. If you are slow, you may only catch one, if fast, perhaps 2 or three. Over the course of the day, this can be the difference between 9 fish or a limit of 25 as it is here in Wisconsin. This affects how I bait my hook.
When fishing with live bait I often use eurolarvae or spikes. These smaller maggots are more durable that the stand by waxworms and are shorter increasing hooksets on short strikes. The other advantage to spikes is that I can use 3 or 4 of them at a time. This means that after I get down to a fish and catch him, I don't have to rebait saving dozens of valuable seconds before the school moves on.
In some cases I opt not to use live bait. Plastics are revolutionizing the way we fish pan fish through the ice and I believe no different. Commonly called "nail tails" these little slivers of soft plastic come in a variety of sizes and display awesome action. This means I can fish sometimes all day without rebaiting and allows me to out perform what I may have done with live bait.
Lastly one thing you will want to watch out for is suspended fish. When fishing perch and crappies you will find that many times these fish show up on your locator much higher than one foot off the bottom. This is because these moving fish do not always stick to the bottom when moving from a transition area like a flat to a river channel and back up. This is because it doesn't make much sense to them to swim the extra distance down and back up the drop off. You will really want to pay attention to these fish as they are typically cruisers looking for food and they can at times be almost a guarantee fillet if you get to them in time.
This is a quick overlook of how I approach deep water pan fish. I hope you take the time to try it as this method may help you better enjoy ice fishing throughout the whole season rather than just early or late.