just like the spawn, water temp has nothing to do with where wintertime crappie are located.
Water temp has everything to do with both.
http://www.in-fisherman.com/biology/science-of-shad-winterkill/water temp doesnt get cold enough long enough in texas for temp to have much of an affect on shad. I couldnt count how many times I recall reading that shad start to die off at around 52 degrees, and the science in the above article proves this is simply not true. if water temp dictated where shad were all winter, I could go to one creek on waco thats always warmer than everywhere else, and there should be so many crappie back there you could walk across them.
Same thing with spawn, ive heard legends like charlie pack, to whitey outlaw saying that crappie always go to warmer water to spawn, and will be in shallow water, NOT TRUE. You can watch old videos
of charlie pack fishing creeks on lake waco, and not catching fish, scratching his head while saying, with the water temp at 60, they should be here. yet they werent.
I believe the availability of a food source for the shad such as plankton and daphnia, (ever heard of them)? have a much larger part in where shad and crappie will be, all thru the year. Daphnias rise and fall in the water column according to sunlight penetration . As humans we tend to think in terms of what would be acceptable survival conditions for us, not fish. Ive seen goldfish frozen solid in a birdbath for a whole day, and when it thawed out, they were swimming around like nothing happened. Todd Huckabee made a u tube vid and said if it depended on water temp, the crappie up north in canada would never spawn, and he is right.
Crappie are usually never too far away from thier food source, and shad are never too far away from thier food source, no matter what the water temp.
Same with summertime fishing in the blazing heat, folks think crappie are sitting on top of the piles in the morning because its 5 degrees cooler in the first couple feet of surface water than it is at high noon. The temp has nothing to do with it, its the light penetration and where the food source are hanging at.
Just some things to think about when you fish a creek for 3 days and dont catch a fish, but its 5 degrees warmer than everywhere else youve fished on the lake.