Woodpeckers with Three Toes

Black-backed Woodpecker

Black-backed Woodpecker

Most birds have four toes. The toes of most perching birds, shorebirds, and gallinaceous (game) birds are arranged in an anisodactyl arrangement – that is, three of the toes point forward while the first toe, called the hallux, points backward. This arrangement is evident in the tracks of a Ruffed Grouse in the snow, or the tracks of a sandpiper or crow on the mudflats of your favourite river or beach. Woodpeckers, Osprey, owls and cuckoos, on the other hand, have a zygodactyl arrangement of toes: the first and fourth toes point backward while the two middle toes point forward.

However, three woodpecker species exist which have only three toes. Two (the Black-backed Woodpecker and the American Three-toed Woodpecker) are found in North America, while the third (the Eurasian Three-toed Woodpecker) is found in the Boreal regions of Europe and Asia. These species all inhabit coniferous forests where they feed chiefly on wood-boring beetle larvae. The American Three-toed Woodpecker has the northern-most breeding range in North America, while the Eurasian Three-toed Woodpecker has the northern-most breeding range in Eurasia. These two species were considered one species until 2003, when they were split because of differences in voice and in mitochondrial DNA sequences. All are believed to have a common ancestor which lost the first toe, the hallux, over time.

The fourth toe is not fixed in a backwards direction, but is able to rotate sideways or even forwards as the woodpecker moves up and down a tree. It is thought that woodpeckers with four toes only use three toes to grip the tree trunk, while the fourth is kept beneath the leg or extends out to the side, thus limiting the amount of force a woodpecker is able to deliver while hammering on a tree trunk. Woodpeckers with three toes do not need to accommodate this extra toe and are able to extend their body back further from the tree when it strikes.

Because they live chiefly in the coniferous Boreal forest, the Black-backed and American Three-toed Woodpeckers can be difficult to find. However, in some winters, these two species move south of their normal breeding range in irregular irruptions. While the American Three-toed Woodpecker is the less likely of the two to wander south, both species’ attraction to recently burned areas and wood-lots with many dead or dying trees can make them easier to find them if they are present. Ottawa is a good spot to see Black-backed Woodpeckers in the winter, especially this year with so many ash trees succumbing to the Emerald Ash Borer infestation. Stony Swamp in particular is a magnet for them, and when I returned to Old Quarry Trail last weekend I found one female working on a tree next to the path at about knee-height.

Black-backed Woodpecker

Black-backed Woodpecker

She wasn’t anywhere near the place where I had seen the two female Black-backed Woodpeckers the previous weekend, and at first I thought I would miss this species on this visit. There were plenty of Downy and Hairy Woodpeckers around, and when I heard this Black-backed Woodpecker tapping away I thought it was another Hairy at first. Then I circled around the tree trunk and realized it was, in fact, the Black-backed Woodpecker. She wasn’t flaking off the bark as I had seen her do previously, but was drilling small holes in the trunk of the tree. She was successful in finding lots of insect larvae.

Black-backed Woodpecker

Black-backed Woodpecker

I watched her for a long while, knowing that with spring on its way, these woodpeckers would soon be returning to their breeding grounds further north. It would be wonderful if a pair or two stayed and decided to breed in the area, but with so few males around it seems unlikely.

Black-backed Woodpecker

Black-backed Woodpecker

Because she was only a few feet above the ground, and so close to the trail, I decided to shoot some video. I love how at one point she stops tapping long enough to take a deep breath and release a sigh. If you watch closely you will also see a chickadee fly in and land briefly on my camera looking for food! I don’t know how I managed to keep the keep camera still when that happened; it’s one of the funniest things that’s happened to me while shooting video.

The toes of the woodpecker aren’t really visible in the video. The video I shot on New Year’s Day is much clearer, and shows how the third toe can rotate to the front or back, as well as be used to grip a thin stem next to the trunk.

While the Black-backed Woodpecker can be relatively easy to find in Ottawa in some winters, the American Three-toed Woodpecker is much less common in our area. I have only seen one, and that was back in 2007. Two have been reported in the Ottawa area this winter: one out in the east end which was seen once and then never re-located, and another in Gatineau that has been regularly observed on the same street for at least two months. Deb and I finally decided to try for it on March 8. The weather was supposed to be clear that day, but by the time we arrived at our meeting place a thick snow was falling. We decided to head out anyway, and were lucky to find it after picking out quite a few Downies and Hairies in the same area. It was working on a tree right next to the road, and we were fortunate to see it as it stayed only about 10 minutes before flying off behind a nearby house. Unlike Black-backed Woodpeckers, the American Three-toed Woodpecker has the same black and white barring on its back as it does on its flanks.

American Three-toed Woodpecker

American Three-toed Woodpecker

Of course, the weekend wouldn’t be complete without a stop at Appaloosa Park on my way home to check on the male Northern Shoveler:

Northern Shoveler

Northern Shoveler

There was still a large number of ducks overwintering along the tiny creek when I visited; can you spot the shoveler among them? (Click to enlarge.)

Ducks at Appaloosa Park

Ducks at Appaloosa Park

Seeing both three-toed woodpecker species in one weekend was a special experience that will probably not soon be repeated. I would have tried for the Black-backed Woodpecker after leaving Gatineau in order to see both species in the same day, except the snow was falling too hard to want to spend a lot of time searching Old Quarry Trail.

Although Ottawa winters are often longer and colder than winters in the rest of southern Ontario, as a birder, I feel privileged to live in a place that receives its fair of northern species in the colder months of the year – from the Bohemian Waxwings and the winter finches to the seldom-in-a-lifetime Gyrfalcon at the Lafleche Dump and these wonderful northern woodpeckers that add such beauty to the winter woods.

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4 thoughts on “Woodpeckers with Three Toes

    • Hi Christian,

      Thanks for the comment and the link to your lovely blog (I did come across that post while researching this one). I guess this post is misleading in suggesting there are ONLY three woodpeckers with three toes, but my goal was to focus on only the two similar Ontario species, which turned out to be three species of the coniferous boreal forests in the northern hemisphere when I learned about Eurasian Three-toed Woodpecker. I only blog about the species I know, so if I left any woodpeckers out it’s because I haven’t met them yet!

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