NEDOC, a quick observation, and by no means definative: this past winter I kept a few YP, BG, GSF, and goldfish in an aquarium in our partially heated garage. When I allowed the water temp to drop to 50 degrees, the sunfish would not feed; the YP would take earthworms. The goldfish continued to ravenously gobble pellets, meal worms, and earthworms.
While goldfish are not carp, it could be that feeding in your pond when water temps are lower than the 50s would mainly benefit your carp. Not good, eh? You might be able to use this to your advantage however, to lure the carp to a spot in the pond where they could be efficiently netted.
Just a thought.
