Besides owning my own flock of twelve ducks, we also own 6000 Pekin ducks for egg production, split among three houses with 2000 in each. Each house has their own lights, keeping them laying all year round. They are fed in the morning, and bed down at night. They have heaters in winter, and fans in the summer. They have water lines which they drink from, which are available at all times. Egg production out of these houses in total was 3519 right before Thanksgiving, all combined. However, right after Thanksgiving, something caused our ducks in house 2 and 1 to drop drastically. Our total dropped to 3092 eggs. A loss of 500 eggs in a day is almost unheard of. This has happened for the past three years, all around the same time frame. House number 3 remained unaffected, oddly enough. What could cause this to happen? Nothing, to our knowledge, is getting in and scaring them, nor do we have anything in there that changes. The only thing that comes to mind is that it became horrendously cold a few nights before they had the drop, although the only house that suffered any cold damage was house number three, which froze the waters lines. Yet, as said, there was no effect on them. This has stumped my grandfather, grandmother, wife, and I for the past three years. Any help would be appreciated.