I'm new. We live in the suburbs and keep ducks for eggs. Our two are laying less after three years. We plan to get three new ducklings this spring. Anyone in Ohio have Anconas? We currently have a Cayuga, Golden Three Hundred, and had a Welsh Harlequin.
Thermacare packs from the pharmacy stay warm 8-12 hours. You could also fill a 2 liter bottle most of the way with hot water and put lid on. They will huddle together. Keep them covered to keep the warmth in.