You saw what kind of owl? Murphy's Law in nature

I've been a naturalist for decades and I have come to accept the fact that Mother Nature hates me. If I schedule a stargazing program, it will be overcast and the owls will be hooting.

If I schedule an owl hike, all the owls will be in Indiana and the stars will be twinkling. This natural Murphy's curse was broken last February.

Stillman had an owl hike on the calendar and it was a bitter night. Much to my surprise, a large group of people arrived despite the frigid temperature. So, we divided them into two groups of roughly 20 each. One group went down the trail to the left and the other went to the right.

Listening to these groups crunch their way down the frozen trails further convinced me that any sensible owl had certainly left the county! I hung back contemplating my explanation for what I was convinced would be a crowd of disappointed and frozen visitors.

Negative attitude aside, I had been listening for owls for weeks prior to the hike. The owls I had been hearing regularly were not the usual suspects, screech or great horned owls. No, I had been hearing Northern saw-whet owls.

Diminutive owls

One of my old owl books divides owls into different size classes. A great horned or snowy owl is super large, a barred owl is large, a common barn owl is medium, and a Western or Eastern screech owl is small. Where does that leave the saw-whet? The northern saw-whet is filed under very small.

How small? It weighs less than three ounces and stands eight inches high with a 17-inch wingspan. It is the smallest owl east of the Mississippi. It can easily be identified by its lack of ear tufts, white V-shaped eyebrows, and robin-red streaking on its chest.

This little predator dines on mice, voles, shrews, and insects. It nests in tree cavities, especially old flicker holes. It ranges across the U.S. up to southeast Alaska.

Many saw-whets move south in winter, with noteworthy concentrations in spring and autumn around the Great Lakes. Spring migration probably starts in mid- to late February. This is also the time the owls are particularly vocal.

Secretive saw-whets

Finding one is the challenge. There are two ways to find a saw-whet, the easy way and the hard way. The easy way is to go where another birder told you they saw one.

The hard way is looking for clues. I remember repeatedly visiting an old Christmas tree plantation, part of a forest preserve, where I had noticed small owl pellets on the ground. (Pellets are undigested fur and bones that owls nicely package and spit up under their roosts.) I was't sure if they were from a screech or a saw-whet.

The evergreens were nearly 60 feet tall and seeing something perched near the top was a challenge. As I walked around I noticed whitewash (bird feces) streaking the side of one of the tree trunks.

Finally, with the help of another bird watcher, we found the little dickens, a saw-whet about 50 feet up perched on a branch against the trunk. There was only one small spot where you could stand and get a clear view of the bird with binoculars.

Whet's in a name

This owl was doing what saw-whets do during the day. They hide in some spruce, pine, or cedar and wait for nightfall to go hunting and live their nocturnal lives.

This brings us back to that hike at Stillman and this owl's name.

It is commonly believed that this owl earned its name from its call. As the story goes, it was thought to sound like a saw blade being sharpened on a whetstone. Having sharpened a knife on a whetstone or two, I had my doubts about this sound comparison explanation.

Another more plausible explanation stems from what this bird is called in French-speaking Canada, "la chouette." Chouette (pronounced "shoo-ett") refers to any small, "earless" owl. Our "saw whet" is probably an 18th century Americanism for this French Canadian term.

Linguists will recall that Chicago got its name from the Native American word "shikaakwa" for wild onion or garlic. Early French explorer Robert de La Salle wrote that word as "Checagou" and here we now are with Chicago.

Enough about human sounds, let's get back to the saw-whets.

Nocturnal eavesdropping

The call I had been hearing on those February evenings was a mechanical repetition of bell-like notes or toos repeated at a rate of, roughly, 100 times per minute. When I sent the trail leaders out, I told them to play the saw-whet's calls on their phones and see if they got a response. As you'll recall, one group went to the left and the other to the right. While I knew saw-whets were often unconcerned with being observed, I also was expecting Murphy's Law to take effect.

After the two groups had covered some ground, the leaders played their phone owl calls. Sure enough, each group got a response. Not surprisingly, the group on one trail thought they were hearing the saw-whet call being played by the other group leader and vice versa.

The thing about these recordings is that they are not continuous, they come to a pause. The owl call they were hearing was not pausing. It was a nonstop series of staccato whistles.

One of the leaders realized that this was an actual saw-whet owl and it was nearby. She told the hikers this and one of them said, "You mean like that," pointing to a saw-whet perched on a leafless branch barely six feet up and just a couple of feet in from the trail.

Everybody in that group got a clear and distinct view of this vocal little owl.

Like I said, this will NEVER happen again.

• Mark Spreyer is the executive director of the Stillman Nature Center in Barrington. Email him at stillmangho@gmail.com.