Monday, March 15, 2010

Hairy & Downy Woodpeckers

By Susan Benson,
Director of Education

“What are the red and white woodpeckers at my feeder? Are they the same bird or just an adult and young bird?” These are questions I have been asked by several people recently. I have also enjoyed both of these species at my own suet feeders. They are two species, the downy and hairy woodpecker. These birds have many similarities. They are common throughout most of North America. They both visit our suet feeders. They are the only common woodpeckers that display a vertical white stripe on their back. The males of both species have a red patch on the back of their head. However, there are also many differences between them, some obvious, and some more subtle.

Two features that make the downy woodpecker easier to identify are the size and bill. The downy woodpecker is much smaller, approximately six to seven inches long. Their bill is shorter, smaller than the width of the head, and about one-third as long as the hairy woodpecker. The white outer tail feathers are barred in black, giving the bird a spotted effect. They also have a squeaky call and slower drum in comparison to hairy woodpeckers. There are other characteristics and behaviors to look for when comparing downy and hairy woodpeckers. The hairy woodpecker forages along trunks and main branches of large trees, with an erect posture, while downy woodpeckers use smaller branches.

What makes these two woodpeckers different? The downy woodpecker joins flocks of chickadees and nuthatches. Flocking with mixed bird species is an advantage as these birds spend less time watching for predators, and have better luck finding food. During the winter, males and females split up to look for food, and males seem to prefer small branches and weed stems, while females feed on larger branches and trunks. Both sexes of “downys” find foods that larger woodpeckers cannot, so downys can be found feeding on insects they find on plant stems and goldenrod galls, round ball on the stems, in which fly larvae are living inside. Downy woodpeckers also eat beetle larvae, ants, or caterpillars in wood or tree bark. They also eat berries, acorns and grains, and are common suet and sunflower seed eaters. They have been observed drinking from hummingbird feeders. They sometimes even hop across the ground for food.

Downy woodpeckers excavate nesting holes, taking up to three weeks to make, with an entrance that is round, but only up to 1.5 inches across. The best place to look for an entrance is in a small, dead tree stub that is around seven inches in diameter, on the underside of the snag. Sometimes their excavations can be found inside of the walls of buildings. They prefer open deciduous woodlands, and their dead nest trees are sometimes filled with fungus that makes excavation easier. They drum against wood as a way to find their mate or to set up territory, and downys will drum more in the early morning.

Hairy Woodpeckers are more common in mature woodlands, and will be found in coniferous deciduous, or even mixed forests with medium to large trees. More than seventy-five percent of their diet is made up of insects, as they prefer wood-boring beetle larvae, bark beetles, ants, and moth pupae. They eat many other types of insects as well. They will drink sap that is leaking from trees. They are often seen cleaning up a site after a pileated woodpecker has finished. Around twenty percent of their diet is made up of fruit and seeds, and they also visit suet and sunflower feeders. They do not feed on weed stalks or plants like the downies, but sometimes forage at the base of trees.

The entrance to a hairy woodpecker nest is a cavity with an opening two inches tall and 1.5 inches wide that takes up to two weeks to create. “Hairys” are a little different as they excavate their nests in the dead stub of a living tree, or in a dead tree, also with their entrance on the underside. The cavity is often in a branch or stub that isn’t perfectly vertical, with the entrance hole on the underside, which perhaps keeps flying squirrels or other woodpeckers from taking over their nest. These birds also drum against trees, more quickly than downy woodpeckers, and their drum is about ten times per minute.

I find that writing these Nature Watch articles makes me look at the beauty in nature I often see in a different way. So, for those who are looking to identify these woodpeckers, or other birds at their feeder, here is a simple tip. First take a look at the overall size of the bird. Size is a reliable field mark, but is difficult to judge when looking outdoors. Some people will measure their feeder, or mark different lengths on their feeders to help them judge the size of birds visiting their feeders. Happy birding!

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