While many duck species are recognized for nesting on the ground, a fascinating group of ducks defies this by choosing elevated tree cavities for their breeding sites. These exceptions demonstrate a unique adaptation to their environments. This article explores these cavity-nesting ducks, their ecological benefits, and their nesting and duckling development.
Duck Species That Nest in Trees
Several duck species are known for their preference for nesting within tree cavities. The Wood Duck, a vibrantly colored species, frequently utilizes natural tree hollows, often those formed by broken branches or rotting heartwood, and readily accepts artificial nest boxes. These cavities can be situated anywhere from 2 to 60 feet above the ground, typically near or directly over water sources. Wood Ducks possess sharp claws, an adaptation that assists them in perching and navigating tree bark.
The Hooded Merganser, a smaller diving duck, also selects tree cavities or hollow tree stumps for nesting, often choosing sites close to water. Their nests are commonly found 10 to 50 feet high, though they can be as elevated as 90 feet, and these ducks also readily adapt to human-provided nest boxes. The Common Goldeneye seeks out holes in live or dead trees, frequently using abandoned Pileated Woodpecker cavities. They often return to the same nesting area year after year.
Buffleheads, one of North America’s smallest diving ducks, are obligate cavity nesters. They primarily rely on old nest holes created by Northern Flickers, or sometimes Pileated Woodpeckers, and also use nest boxes. These nest sites typically range from 2 to 10 feet above ground but can be found up to 50 feet high.
Advantages of Elevated Nesting
Nesting in elevated tree cavities provides several significant advantages for these duck species. A primary benefit is enhanced protection from ground-based predators. Animals such as raccoons, skunks, foxes, and snakes find it difficult or impossible to access nests high up in trees. This reduced predation pressure contributes to higher nesting success rates.
Elevated nests also offer a measure of safety from fluctuating water levels. Nests located near wetlands or flood-prone areas are protected from inundation, which can destroy ground nests during heavy rains or rising river levels. Tree nests are generally less accessible to human disturbance, providing a more secluded environment for incubating females. Tree cavities can also offer more stable thermal conditions compared to exposed ground nests, providing better insulation against extreme temperatures.
Nesting Behavior and Duckling Development
The nesting process for these tree-dwelling ducks involves specific behaviors. The female typically lines the chosen tree cavity with soft down feathers plucked from her own breast, creating a warm and cushioned environment for her eggs. Incubation periods vary slightly by species, generally lasting around 29 to 37 days. For instance, Wood Ducks typically incubate for approximately 30 days, while Hooded Mergansers incubate for 29 to 37 days.
Shortly after hatching, ducklings undertake an instinctual leap from the tree cavity within 24 to 48 hours. Guided by their mother’s calls from below, these tiny, downy ducklings jump from heights that can range from a few feet to over 50 feet, with some Wood Duck ducklings even recorded jumping from as high as 291 feet. Their small size, light weight, and soft, fuzzy down feathers allow them to absorb the impact of the fall without injury.
Upon landing, the ducklings are immediately precocial, meaning they are well-developed and self-sufficient. They can walk, swim, and forage for food almost immediately, following their mother to the nearest body of water. The mother guides them but does not provide food; they begin feeding themselves right away.