The American Three-toed Woodpecker

Our Rarest Woodpecker

American Thrree-toed Woodpecker [C Melanson Photo]

The American Three-toed Woodpecker (Picoides dorsalis) is our rarest woodpecker.  The individual shown above was recently reported from Miscou Island.  This species is rare enough that we get sightings only once every few years.  Given that its preferred habitat is coniferous forest with dead and dying trees and that it prefers northerly areas often of high elevation, people would not encounter this species as often as species that prefer more southerly habitats.  In the past there have been reports from Mount Carleton Provincial Park.  I remember a sighting from the late 1950s from the Fredericton area and I saw one at Kingsley, NB in October, 1970.

The American Three-toed Woodpecker is a 'Picoides' woodpecker, a genus it shares with the Black-backed Woodpecker, the Downy Woodpecker and the Hairy Woodpecker in this area.  There are other Picoides species but they do not occur here.  Sharing the same genus usually means that this species shares anatomical structure, behaviour and habitats with others of its genus.  The American Three-toed Woodpecker is shaped like the species mentioned above and shares similar life histories.  However, it more closely resembles the Black-backed Woodpecker which is also a three-toed woodpecker.

So what significance does 'three-toed' have?  Most woodpeckers are four-toed.  That manifests itself usually with two toes facing forward and two backward.  One can easily see this as the bird moves up the tree trunk, clinging by the claws on its toes and propped up by its stiff tail.  In the three-toed woodpeckers, they show two toes facing forward and one out to the side or behind.  So they move up or down the tree trunk by clinging with the two front toes, somewhat with the side or back-facing toe and propped up with the stiff tail.  In the photo below notice the three toes.

American Three-toed Woodpecker [C Melanson Photo]

The American Three-toed Woodpecker is just a bit smaller than the Hairy Woodpecker with a length of 22 cm/ 8.75".  The biggest difference (other than the three toes) between the three-toed woodpeckers and the other Picoides woodpeckers is the presence of yellow on the crown.  All the others show red.  The male American Three-toed Woodpecker has a yellow patch on the top of the head as shown in the photos above.  This is also present in the young birds, both male and female.  The adult female shows plain black on the head or it may be speckled with a small amount of white.  

Identifying the American Three-toed Woodpecker is relatively easy.  It looks dark in colour on quick view.  You then have to look closely to distinguish it from the Black-backed Woodpecker which has a solid black back.  The American Three-toed has horizontal black and white stripes on its back.  Sometimes these are hidden if you are viewing the bird from the side.  So, look closely.  The Black-backed is slightly larger but that does not help much in telling them apart.

Besides the white stripes on the back, the American Three-toed has mostly black on the back except for some white barring on the primary wing feathers.  The underparts are white with black barring on the sides.  The tail is black with white outer-tail feathers.  On a quick view the female could be mistaken for a Hairy Woodpecker.  

American Three-toed Woodpeckers are North America's most northerly breeding woodpecker.  Their range covers a vast area from northern Labrador, across northern Ontario and the Prairie Provinces to norther Alaska and Yukon.  In the west they range southward in the mountains to New Mexico and Arizona.  Their Canadian southern boundary is close to the 49th parallel to southern Quebec, northern NB and Newfoundland.  They are non-migratory.  However there can be movement southward in severe winters or in dwindling food supplies.  Their population is thought to be stable.

They are normally sparsely located throughout their range.  They are sometimes found in higher densities in areas with many dead trees.  This can be after a forest fire and that undoubtedly is what has attracted this bird to Miscou Island.   There was a small forest fire there in recent years.  

The American Three-toed Woodpecker nests in a cavity about 12 m/ 45 feet up in a dead tree, usually a conifer or a poplar.  Incubation takes about 12 to 14 days and is carried out by both the male and female.  They feed on larvae of tree-dwelling insects, spiders, and some berries.  They also will eat bark cambium.  

In 2003 the 'Three-toed Woodpecker' was split into the American Three-toed Woodpecker and the Eurasian Three-toed Woodpecker.  These two species are nearly identical in appearance but they differ in voice and mitochondrial DNA (iBirdPro).  We are not likely to see its Eurasian cousin but it is interesting to know that its close relative is successful in Europe.  

It is interesting to speculate what the spruce budworm spraying program and clearcutting have done to the presence of this species in NB.  Feeding on tree-dwelling insects in dead trees is a vital part of the ecology of the forest.