The wood duck, Aix sponsa, is one of North America's most colorful waterfowl and, although rarely seen because of its reclusive habits, is relatively abundant along the Atlantic Flyway. Wood ducks form pairs during the winter. In early spring, the female searches for a tree cavity where she lays their eggs and incubates them. After the ducklings hatch, they jump from the nest to join their mother on a nearby pond. Due to multiple factors, wood duck populations reached record lows at the turn of the 20th century, but efforts using artificial nest boxes that replicate natural cavities helped populations rebound. Several wood duck nest boxes can be seen on the Arboretum grounds.