Who's Who, Downy or Hairy Woodpeckers

The most obvious difference is size. The hairy woodpecker is about 1/3 longer than the downy and weighs almost 3 times as much!

Yet when you see one alone, without the other for comparison, it can be tricky to identify it on size alone.

So look at the bill. The downy's bill is tiny in proportion to the head.

The hairy's bill is large. Here's a thought experiment. Mentally turn each bird's bill around, so that it points toward the back of the bird's head. How far across the head does it appear to extend?

The bill of the downy woodpecker (a female in this case, on the left) is noticeably shorter than the width of the head. The bill of the hairy woodpecker (which happens to be a male, on the right, with red on the back of his head), goes almost the full width of the head. That's the most reliable way to tell the two apart. Even if you see one alone, at such a distance that you can't evaluate the bird's size, you'll be able to notice how long the bill is compared to the head. Another clue is the white outer tail feathers. On the hairy woodpecker, the outer feathers are pure white. On the downy, there are usually black or gray spots along the sides of the white outer tail feathers. You can just make out the dark spots on the side of the downy woodpecker's tail in the photo above.

Their calls distinguish them also. The rattling call of the hairy woodpecker is mostly on the same pitch. But the downy's call drops down (for downy) in pitch.

In each species, the male and female are about the same size. If you see a big difference between the size of two of these woodpeckers, you'll know you're looking at a downy and a hairy, not male and female of one species.