The Wood Duck (Aix sponsa) is one of the most colourful birds at the Sanctuary and is present year-round. The species gets its name from its habit of nesting in tree cavities, using old woodpeckers holes or artificial nest boxes. For most of the winter, about 40 are present and found mainly among the tall Douglas Firs of East and North Dykes where there are shaded shallow sloughs with overhanging branches to roost on. As early as January, we start to see them displaying on fences and in trees. This marks the start of their courtship, and the place becomes noisy in February with the various sharp whistles of the males ("drakes"), and odd squeals and mutterings of the females ("hens") as they mill around in groups, sorting out who is going to mate with who, and which duck box is the best nest site.
Nests are built in March or April, with ducklings hatching in May and June. They do not gather nest material, using just the loose wood debris inside the hole or the wood shaving provided in boxes. These materials cushion the first few eggs, and by the time there is a full set of eggs ready to incubate, the hen has pulled downy feathers from her chest to make an insulating blanket around the eggs. Incubation ltakes 28 to 32 days, and the eggs all hatch within a day of one another. After a day, the ducklings climb out of the nest and drop down to the waiting hen below. We rarely witness this early morning drop, but the new ducklings are quite noticeable on their first day, racing across the surface of ponds to follow their very vocal mother. Usually, a hen lays 12 to 14 eggs. Some broods can be quite large (more than 15 young), which usually indicates a "dump nest" has happened, where another hen has deposited extra eggs in a nest. Often this is done by a young female that has not yet found her own nest site. Ducklings stay with the hen for three months until they can fly.
During the summer, as ducklings grow to adult size, the adult birds go through the gradual annual moult of their feathers, tending to also be flightless and a lot less conspicuous. By late summer, all Wood Ducks are a bit scarce, but may be exploring the nearby sloughs of the island and Fraser River. In the fall, they slowly return to their favourite haunts and are in fresh, showy plumage.
We have posted photos of this duck and other Sanctuary birds on Flickr.