Winter Buteos
Buteos are the large hawks that we often see perched atop powerpoles, trees or on fences, especially in open country but some prefer the forests as well. The 3 common buteos that we see around Kamloops are the Red-tailed Hawk, Swainson’s Hawk and Rough-legged Hawk. The Ferruginous Hawk has been seen periodically but rarely. One other buteo that has been seen recently during the fall migration is the Broad-winged Hawk which may become more frequent. The Swainson’s Hawk only occurs here during the summer and will not be a focus of this post, but I will touch on it.
All of the buteos exhibit plumage colour phases which in addition to age variations make them tricky to identify for many people. While this post won’t come close to helping distinguish all of the variations, it may help you identify our common winter birds.
The most common buteo here is the Red-tailed Hawk. Colour phases range from lighter birds through a gradation to almost black. Variable amounts of reddish tones can be seen in the adults but those namesake colours are lacking in juveniles.
This is a fairly typical western race of Red-tail with a brown hood, dark throat and broad dark belly band which can vary in characteristics.
Here is the same bird from behind. The brick red tail with varying width black bars is quite typical but again there can be some variation. No other local buteo has a red tail.
Here is another western “calurus” variation. Note the additional amount of white in the throat and more white in the brown hood.
Note the different belly markings on this bird and the light banded tail. It is a juvenile bird that has not molted in its new colours. The next photo shows a different immature but you can see the barred tail.
Another juvenile light form in flight. The barred tail is very evident and even on the top side, there would be no rufous colouration. Note the belly band but also one more critical identification mark in adult and juvenile birds.on the leading edge of the wings is a dark mark spreading out from the body towards the outer wing. This is called the patagial mark and it is typical of Red-tailed hawks but is only seen in flight from below.
This is a rufous colour morph of Red-tailed Hawk. The dark belly is still visible but otherwise looks quite different from the lighter forms.
From behind, this same rufous morph shows red in the tail with faint, darker cross barring indicating that is in adult plumage.
Continuing along the colour extreme in the next photo is a dark phase Harlan’s Hawk. It is still considered to be a race of Red-tailed Hawk, but taxonomists have debated whether it should be its own species.
The colours are more of a deep chocolate brown.
Another Harlan’s Hawk but note the white base of the tail and a brownish band near the outer tip. There are numerous tail variations in this race and some have no red whatsoever.
The above are a few of the variations of Red-tailed Hawks which can be seen year round at Kamloops. The next most common and the only other buteo in the winter months is the Rough-legged Hawk. They begin arriving in migration during the last week of September although a few may be as early as mid-September. Some continue south while others remain all winter with spring migration north peaking in April with some birds still being seen into early May.
Rough-leggeds range from very light through almost all black with many variations in between. The most common ones we see here are very light and many are juveniles. Red-tails do not look as light as these birds which are often evident at a long distance being so light.
This is a fairly typical light-phased bird but is a juvenile with a large dark belly band. The head is typically white overall with a lot of white body plumage and variable streaking.
The same individual but note the large dark patch at the bend of the wing called a carpal patch. It is diagnostic and easily seen in lighter-phased birds including adults.
Note the white base of the tail which seen both on the underside and top of the tail. This is a good field mark as there is also a dark terminal band. Be careful not to mistake a Harlan’s Hawk with a white tail base however.
Adult females also have large black belly patches and can be tricky to separate from young birds.
Another juvenile Rough-legged Hawk but more of an intermediate phased bird, not so light as one above and less of a belly band. But the carpal marks are very apparent.
And at the extreme dark end of the spectrum is this dark-phased individual. Less than 10% of the birds we see at Kamloops are of this type. Note light tail base which is evident in flight.
I said I would touch on Swainson’s Hawk. They are a summering bird that arrive about mid-April and are gone by mid-September. They show colour phases and juvenile plumage variations as well.
This is a typical light-phase adult with a dark upper breast area. The big orange cere at the base of the bill is quite characteristic.
With rufous extending farther down onto the belly and legs, this is more of an intermediate rufous phase bird. Note the typical white throat.
Juvenile Swainson’s Hawks are more darkly speckled but have the white throat and orange-yellow cere.
And lastly, a lovely dark phase Swainson’s Hawk. Not very common around Kamloops but worth looking for.
So as a final reminder, our winter Buteos will inevitably be Red-tailed Hawks and Rough-legged Hawks. Our summer buteos will be Red-tailed and Swainson’s Hawks. Broad-winged Hawks seem to be increasing as a fall migrant and Ferruginous Hawks are a rare wandering bird seen only occasionally in the past 30 years.