BIRDING BY HINDSIGHT: A Second Look at Owls

A second look? How about a first look? Typically nocturnal and consequently relatively difficult to see, owls invariably rank prominently on many birders’ “most wanted” lists. Yes, owls can be heard by those willing to venture out at night, but they often end up on the list as “heard only”.

Fortunately, the visual and aural identification of most owls is pretty straightforward — at least in Minnesota — so it usually only takes one look or listen to accurately determine their identities. Still, there are a few potential problems lurking out there which might mislead those birders who are still in the dark when it comes to identifying owls. And now is as good a time as any to address these with winter rapidly approaching. ’Tis the season, after all, when a birder's thoughts turn to northern owls, especially since the past two winters forced so many Snowy, Northern Hawk, Great Gray, and Boreal owls into southern Minnesota and beyond.

A Heart-shaped Face in the Barn

It would sure be a lucky find, but there is always the possibility that some day you or someone you know actually turns up an owl in a barn — just like the ones in Dakota County not too many years ago. It would then be a Barn Owl, right? Well, probably, but not necessarily. It seems that Great Horned Owls on occasion have been known to roost or even nest in buildings, barns included. And once I was surprised to find two Burrowing Owls roosting by day in a large storage shed in Texas.

Of course, given a decent look at a Barn Owl and all its field marks, this owl doesn’t really resemble anything else. Its combination of a heart-shaped face, brown eyes, essentially all-white underparts and under wings, and unique blend of solid buff and gray on the back and upper wing surface make this a relatively easy species to identify. Be careful, however, not to concentrate too much on one field mark to the exclusion of others. As noted below, Barred Owls also have brown eyes and a heart-shaped face, and any owl flying overhead can appear white at night when illuminated by flashlight or car headlights.

Two other caveats. First, since the Barn Owl is about the most strictly nocturnal of all owls, it is not something birders observe hunting very often. It was quite a revelation, therefore, the first time I saw one hunting at dusk: its flight style was identical to the Short-eared Owl’s, so much so that I initially identified it as a Short-eared.

And, second, since the Barn Owl has a reputation for its unnerving calls which can sound quite frightening (especially when you’re alone), more than one owler has incorrectly assumed that unfamiliar sound heard in the dark was by default a Barn Owl’s cry. However, as noted below, some Long-eared Owl calls can literally sound like someone screaming bloody murder. And juveniles of all owl species can give food-begging cries that are quite atypical, difficult to describe, and therefore tempting to inaccurately ascribe to the Barn Owl.

An Eerie Lack of Ears

It was nothing short of amazing for that Boreal Owl to spend much of last winter at Springbrook Nature Center in Fridley. First, this species of owl hardly ever ventures into southern Minnesota, and, second, winter individuals seldom stay put at a location for two consecutive days, let alone for several weeks!

However, it is actually quite routine for small owls with Boreal Owl-like black facial frames and no visible “ear” tufts to be seen in southern Minnesota. And certainly more of these will appear this fall and winter — and perhaps end up being misidentified as Boreals by those recalling the famous Springbrook owl. But if not Boreal Owls, what are they? Take a second look, and odds are they will turn out to be Eastern Screech-Owls with their ear tufts flattened out of sight. (I’m reasonably sure, for example, that an owl reported as a Boreal several years ago in Winona County was in reality a screech-owl.) It is important to keep in mind that screech-owls, Great Horneds, and Long-eareds frequently appear quite “earless” when they flatten those tufts.

Ascots vs. Bow Ties

Even though the field guides fail to adequately stress the presence of the Great Gray Owl’s white “bow tie” mark, anyone who has ever seen a Great Gray cannot fail to notice how prominent this field mark is, even at a distance or in poor light. There is a potential source of confusion here, however, as I know of more than one birder whose Great Gray sighting ended up being that of a Great Horned Owl. How could this happen? It seems that Great Horneds also have a noticeable white area on the throat, their plumage typically looks more gray than brown overall, and, as mentioned above, they can flatten those ear tufts and have a rounder-looking head profile.

But note the Great Horned Owl’s white throat patch is larger than the Great Gray’s and not as clearly delineated. I’m for calling it more of a white “ascot”, but the thing to remember is the Great Gray’s white “bow tie” is sharply outlined, more contrasting, and it actually has a black “knot” in the middle.

Great Horned Owls may also have the potential for being confused with Snowy and Long-eared Owls. As far as the Snowy is concerned, be aware that the subarctic form of the Great Horned Owl does winter in Minnesota on occasion, its plumage is grayish white overall, and it consequently is a source of confusion with the Snowy.

And, when relative size is unclear, it is not all that easy to tell a Great Horned from a Long-eared. A Great Horned’s ear tufts do not always appear to be shorter and spaced farther apart than a Long-eared’s, as the field guides suggest. When in doubt, try to see the owl’s underparts pattern. A Great Horned does have short vertical smudges below its ascot, but below this it only has horizontal barring; a Long-eared has dark vertical streaks as well as barring down on its breast and belly.

Green-winged Black-capped Owls

As long as birders make sure that whitish owl in front of them is not one of those subarctic Great Horneds, what else could possibly be confused with a Snowy Owl? Probably nothing, although it cannot be stressed enough, as mentioned earlier, that almost any owl can appear whiter than it really is when illuminated by the artificial light of a flashlight or car headlights. This is especially true when flying overhead, since owls are typically paler on their underparts and under wings than on their upperparts.

So, if a Snowy Owl is so easy to recognize, what was that heavily barred owl with the green wing patch and black cap you saw in the Duluth harbor last winter? It seems that owl researcher and bander Dave Evans has been netting, color marking, and keeping track of Snowy Owls wintering in this area for several years. The green on the wing is a numbered wing tag, and the black on the head is a temporary dye which makes the owls easier to spot by day as they sit on the harbor ice.

Even without these artificial markings, however, many birders are surprised to find that many Snowy Owls wintering in Minnesota are not as photogenic or as snowy white as the field guides show. Typically, immature Snowys tend to winter farther south than adults (and to a Snowy Owl, Minnesota is south!), and these immatures, especially females, can be heavily marked with dusky barring overall and are consequently not all that white or attractive. Even the darkest immature female, however, will still have a pure white face, and in flight its under wings are also essentially all white.

So Who Needs Talons?

If any predator were able to successfully hunt by pure intimidation, it would have to be the Northern Hawk Owl. No other bird has as fierce a facial expression (well, the Yellow-eyed Junco does come close), and if you’ve ever had a hawk owl stare at you it’s not too hard to imagine how a mouse might simply drop dead from fright when confronted with this owl’s glare.

Actually, the head pattern of a Northern Hawk Owl is remarkably similar to that of a Boreal Owl. Both owls have black facial frames, a yellow bill and white-spotted forehead. They even share the same back-of-the-head pattern: broad stripes of dark and light that to my eye suggest a “skunk-skin” cap. Of course, despite their almost interchangeable heads, these two owls would probably not be mixed up by even the novice owler. The hawk owl is larger with a longer tail, and it is heavily and uniformly barred underneath down to the under tail coverts. It also typically hunts by day out in the open from conspicuous perches in the same area for days or weeks at a time — which, alas, is quite different from the much more elusive and reclusive Boreal Owl.

Northern Hawk Owls and Boreals can be quite difficult to separate, however, when only heard calling on territory. After decades of being mislead by the field guides, birders are finally becoming aware that the male Boreal Owl’s territorial song resembles the winnowing of the Common Snipe. The problem is that the hawk owl, which does nest occasionally in Minnesota, has a similar territorial song, though longer in duration and more on one pitch than a typical Boreal Owl's song (which rises in pitch). However, note that after a male Boreal attracts a female into his territory, he prolongs the duration of his call and holds it on one pitch — and to my ear it then sounds just like the hawk owl’s song.

Owls in the Hole

Finally, an owl that would seem to be impossible to confuse with any other, since no other grasslands owl but the Burrowing is so small and long-legged. (The only other owls which hang around in Burrowing country would be the dissimilar Barn, Great Horned, and Short-eared.) But while birders should have no difficulty identifying this underground-nesting owl, they certainly have difficulty just trying to find one in the first place. In decades past, the Burrowing Owl regularly nested in western Minnesota; now they are scarce enough to have been demoted to Casual status. In fact, for reasons which are not entirely understood, the Burrowing Owl seems to be declining in numbers in many places. In more ways than one, then, this is one owl that’s definitely in a hole.

An Owl Telephone Directory

I still remember that cover of the Minneapolis phone book from several years ago: it featured a nice photo of a brown-eyed owl with a clearly visible heart-shaped face. So why would the telephone company choose the exceptionally rare Barn Owl for the cover of its directory? Well, it didn’t actually. As noted earlier in this article, the Barred Owl (which was on the cover) shares the same eye color and facial frames shape as the Barn Owl.

But no one would actually confuse these two species in the field, would they? Perhaps. I am of the opinion that the report of a Barn Owl family in St. Louis County not too many years ago actually referred to some Barred Owls. The owls were never clearly seen and only glimpsed in a flashlight beam flying overhead (which can make any owl look Snowy- or Barn-white). And the owls were quite vocal, giving several strange calls (as Barred Owls often do, especially when juveniles are begging for food) which the listeners assumed had to be Barn Owl calls.

Barred Owls have an even stronger potential to be misidentified as Great Grays. Several times over the years I have gone to check out a Great Gray Owl report only to find a Barred Owl at the given location. And with so many Great Grays turning up in southern Minnesota during the past two winters, there may be a tendency by novice owlers to assume that any large “earless” owl from now on will be the more glamorous Great Gray rather than the more routine Barred Owl. For that matter, we will never really know how many of those “Great Grays” in southern Minnesota during the two most recent invasions were actually Barred Owls, since not all of them were documented.

When Mating Sounds Boring

This article has already discussed how one might confuse a Great Horned or a Barred owl with a Great Gray. (Again, remember that the Great Horned wears a white ascot, not a black-knotted white bow tie, and that its ear tufts may not always be visible. And, again, just consider the Barred Owl’s eye color, and that Barreds are more likely in most parts of Minnesota than Great Grays.)

It’s also worth commenting here on what a Great Gray sounds like. If you’ve never heard a male Great Gray Owl calling on territory, it’s worth listening to a recording of one. The deep, slowly paced series of hooting typically trails off in pitch and volume at the end, making the owl actually sound quite bored and disinterested in the prospect of attracting a female. He sounds weary, like it’s all he can do to muster the effort to complete his call. This quality and cadence of the Great Gray’s hooting is not only almost comical to hear, but it will also serve to separate it from the calls of the Great Horned and Long-eared Owls – the other owls with low-pitched hooting which a listener might be tempted to ascribe to a Great Gray.

The Owl of the Baskervilles

It was pointed out earlier in this article that the length and position of the Long-eared’s “ears” may not look all that different from the Great Horned’s, and that the ears of both species can disappear from view altogether. The Long-eared’s flight (as discussed below) and calls can also lead to confusion. It seems, as mentioned earlier, the Barn Owl is not the only owl with calls strange enough to unnerve even veteran listeners who claim not to be afraid of the dark.

Barred Owls, especially hungry juveniles, are also good at giving such sounds, but even more uncanny are some of the noises which can emanate from a Long-eared Owl. Besides single low-pitched hoots, Long-eareds also produce dog-like barking sounds as well as a variety of shrieks and screams that can really sound like nothing less than a victim in a Sherlock Holmes murder mystery.

Nothing Flies Quite Like It

Or at least that’s what I used to think about the distinctive flight of the Short-eared Owl. Its curious wing stroke with a noticeable pause at the top seemed to be something unmatched by any other creature capable of flight. (Moths included, by the way: I never did understand how the Short-eared’s flight could be described as “moth-like”.)

Sandhill Cranes, Northern Harriers, Rough-legged Hawks, and even Golden Eagles at times can have vaguely similar wing beats, but what was amazing to me was how much a hunting Barn Owl (as noted earlier) or Long-eared Owl can resemble a Short-eared. Long-eareds especially, since they have a buff patch on the primaries and a black carpal smudge on the under wings, just like a Short-eared. One difference between the two in flight is the pale trailing edge on the wings of a Short-eared, which is not difficult to see and which is lacking on a Long-eared Owl.

And it was just this past spring that Hawk Ridge’s hawk identification ace, Frank Nicoletti, pointed out another Short-eared look-alike of which I wasn’t aware. In the distance was this raptor flying around which behaved for all the world like a typical Short-eared Owl. But it wasn’t even an owl – rather, it was a Cooper’s Hawk doing a courtship flight! Beware, then, not only of Barn and Long-eared owls, but also of courting accipiters (who seem to get a lot more excited about mating than Great Gray Owls).

Going on a Snipe Hunt

Hopefully, by this point in the article, readers will no longer be tempted to misidentify an “earless” black-facial-framed Eastern Screech-Owl as a Boreal Owl. And readers are reminded here to note the similar head patterns and songs of the Boreal and Northern Hawk Owls. It was also pointed out earlier that the territorial song of the male Boreal Owl closely resembles the sound made by a winnowing Wilson's Snipe. But this is worth repeating and emphasizing, since too many references for too long have incorrectly compared the Boreal Owl’s call to that of a high-pitched bell or dripping water. In reality, of course, that description fits perfectly the primary call of the Northern Saw-whet Owl.

So, when listening and looking for Boreal Owls on territory, don’t be misled by the sounds of bells and dripping water. Instead, go hunting for the sound of the snipe. It may just turn out to a Boreal Owl if the sound appears to be coming from one spot in the trees (winnowing snipe are moving around in flight overhead) and if the pauses between the phrases are uniform (the snipe’s winnowing sounds occur at irregular intervals).

As Cute as a Chickadee

Of course, there’s nothing wrong with wandering off in the direction of high-pitched bells or dripping water if it leads to a Northern Saw-whet Owl. After all, there is nothing cuter than a saw-whet – unless it’s the Black-capped Chickadee. (And, as everyone agrees, these are the only two cute birds to occur in Minnesota. So be careful and don’t confuse the two. Note the chickadee has a black cap and throat and eats sunflower seeds; a saw-whet lacks these black markings and may occasionally eat chickadees.)

As mentioned earlier, it is likely that some of those “Great Gray” sightings from southern Minnesota from the last two winter invasions may actually have been of Barred Owls. Similarly, Northern Saw-whet Owls can also be mistaken for Boreals and cloud our conclusions as to how many of those small owls were actually Boreals. Note, however, that Boreal Owls simply aren’t cute: their black facial frames not only can make them look as mean as a hawk owl, but this black outline (which extends down in a “V” to the eyes) also serves as the best distinction between a Boreal and a saw-whet.

Some birders struggle to see whether the bill is pale or dark and whether those white markings on the forehead are spots or streaks, but the presence/absence of facial frames is much easier to see. And while the Boreal Owl is larger than a saw-whet and tends to have a squarer head profile than the rounder-headed saw-whet, these differences are often difficult to determine without direct comparison.