The study looked at duck brood sizes in Maine from 1955 to 2007. They found that brood sizes decreased over time for American Black Ducks, Wood Ducks, Ring-necked Ducks, and Common Goldeneyes. This decline in brood sizes could be a sign of lower productivity in breeding ducks in Maine. The researchers suggest that factors during the breeding season may be affecting duckling survival and overall productivity. This information is important for the long-term conservation of breeding waterfowl populations in Maine.