Another interesting fact about woodpeckers is that the male incubates the eggs overnight, the opposite of most bird species. The guarding and mock incubation continue until all eggs are laid, at which time real incubation starts. One egg is laid per day, with the parents taking one of two roles – standing guard nearby or engaging in mock incubation which lasts usually under 30 minutes. This allows them to replace eggs that may have been lost to poor weather conditions or predators. Woodpeckers are indeterminate egg layers, which means that they do not lay a specific number of eggs. Woodpecker eggs are white, not needing to be camouflaged inside of the cavity. Cavity nesting birds are usually more successful than birds that use open nests, with a higher survival rate for their young because they are protected from poor weather conditions and predators. Northern Flickers are built to withstand the hammering blows needed to create the cavities because of a bone that projects from the top of the upper bill and acts as a stop, as well as having extra cartilage between the skull and the bill for shock absorption. Northern Flicker at nest cavity, By Jan Pallandįlickers create a cavity that they chisel into a tree for nesting purposes. Northern Flickers have a couple of ribs that are abnormally large which allows for extra chest muscle attachment, making the physical demands of being a woodpecker easier. Their tail feathers are also of special design, with a reinforced shaft and pointed tips, creating a sturdy third part of the tripod as they move on the sides of trees. Most of their tail is black, an adaptation for strength where it is needed a great deal.Īnother unique adaptation of the Flicker is the fact that two of their toes point forward and two point backward, this zygodactyl arrangement provides extra grip on the bark of a tree, especially since the fourth toe can be spread more to the side when needed. This is quite necessary when you think of how much time a bird like this is entering and exiting from a cavity to tend to its young. The black color in the plumage of Northern Flickers comes from pigment (melanin) that adds strength and durability to their feathers. The male has black malars, marks that start where the beak meets the face and travel down at an attractive angle on the cheek. Northern Flicker males and females differ very little in their appearance. Two Northern Flickers on a snag, By Jan Palland
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