February 7, 2011

Winter Woodpeckers by Dave Erler

The winter woods seem quiet compared to chorus of bird songs and insect buzzings of early summer, but if you listen carefully the sound of woodpeckers chipping away on tree trunks and branches can frequently be heard. Winter is a mixed blessing for three resident Lakes Region woodpeckers; Downy, Hairy, and Pileated. Insects are in short supply but dormant insects, eggs, larva, and pupa are available beneath the bark. Once a pathway is exposed woodpeckers use their barbed tongues like harpoons to extract these choice morsels. The large red flame-crested Pileated Woodpeckers feed heavily on winter dormant carpenter ants inside the trunk cores of larger trees, especially white pine and Eastern hemlock. Large oblong holes are sure evidence of their activity. Signs of the foraging of Hairy and Downy Woodpeckers are a bit more subtle. Downy woodpeckers often chip away on smaller braches, twigs, and even weed stems. Hairy woodpeckers normally prefer slightly larger branches on more mature trees.
How do you tell the three species apart? Pileated Woodpeckers, due to their large size (almost crow size), are easily separated from the two smaller “look-a-likes.” The Hairy is larger in size than the Downy, but this is not always easy to determine if you are only seeing a single individual. The black and white plumage of both Downy and Hairy are very similar, but if you view them from close enough or through binoculars you may notice the black spots on the outer tail feathers of the Downy that are lacking on the Hairy. Probably the best way to distinguish them is by their relative beak size. The Downy has a smaller bill which appears to be about half the length of its head and has a more obvious tuft of white feathers at the base of the bill. The Hairy’s bill is longer, appearing to be almost the same length as the head, and the tuft of feathers at the base of the bill is much less obvious.
As the winter days gradually lengthen you may also begin to hear the loud, rapid drumming of male woodpeckers. This is not for foraging purposes, but rather a way to advertise as they begin to establish breeding territories. Hollow trunks, limbs, rain gutters, and metal roof flashing are used to get their hormone-driven message out. Woodpecker drumming is equivalent to the songs of male perching birds since woodpeckers are better drummers than singers.
So, next time you are out in the winter woods for a walk, snowshoe hike, or cross country skiing jaunt keep your ears open. They may lead to a peek at one of our resident hammerheads.

Photos show a Pileated Woodpecker (left) and a Downy Woodpecker (right).

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