"I wonder if that's normal for the fish to still have the feed in their bodies after 3-4 days, or maybe is that a result of reduced metabolism due to colder water temps?
The observation certainly peaked my interest! 2 of the perch were stuffed full of pellets, 3 others had some smaller clumps of them in their bellies. We caught them sllooooowwww jigging redworms across the bottom of my deep (~11ft) end. So those 2 that were stuffed with pellets were still after a redworm snack.