Here also is an in-depth article about Larry and his work.
A Quizzical Look
The crisp, cold chill of the morning air cleared the cobwebs from my mind. When I am out and about, I imagine myself fully alert to the wildlife around me. However, I suspect that even at my best, I still miss more than I see. For example, while walking south through the Arboretum, during the early morning, I had no idea there was an owl hunting among the bushes in front of me. I was certainly surprised by the silent flurry of wings when the Barred Owl rose up from the ground and landed on a small branch.
The owl glanced at me and then resumed searching the surrounding trees. The owl's lack of interest in me seemed to imply that I was, 'Too big to eat and too noisy to be dangerous.'
My own thoughts were equal parts - excitement and relief. For many winters, I have been able to check-in on one of the Barred Owls on a daily basis. At some point, I had become aware of one of the resident owls' winter roost. A shaded, horizontal branch deep within a stand of Western Red Cedars was a consistently used spot where the owl silently snoozed through the daylight hours.
Sadly for me, for the last two winters, the owl has apparently found a new resting location. I no longer have a clue where the owl takes its siestas.
As a matter of fact, until I heard a Barred Owl calling just last week, the only owl I had seen in the Arboretum this year was this Great Horned Owl. Since Great Horned Owls are quite capable of eating smaller owls, seeing one always makes me a bit concerned for our resident Barred Owls.
It was certainly a warm feeling of relief to see this healthy-looking Barred Owl going about its business. It reassured me that we still have a good chance of seeing young owlets later this year.
At this point, the owl seemed to be evaluating my daughter's dog, Ginger. The owl's apparent conclusion was, 'Smaller than the human, but still too big to catch and carry.'
Later, while looking at this photo, I was struck by the subtle asymmetry in the owl's facial disk. The disk is the area outlined by the dark brown stripe which surrounds the eyes and beak. This concave, saucer-shape helps Barred Owls to funnel sounds to their ears. Their specialized hearing complements their night vision and their exceptionally silent flight to make them superb nocturnal hunters.
I enjoy trying to identify the individual creatures which live and reside around Union Bay. I have not had much luck with the Barred Owls. So, as I looked at this photo I wondered, Could the elevated dark brown 'eyebrow' above the bird's right eye enable consistent identification? Is this quizzical look unique to this individual?
I began searching my database for Barred Owl photos. A found this 2014 photo which shows the brown stripe on the right side of this owl's face was also higher than the stripe on the left.
Among the 2015 photos, I found a picture of a hatch-year bird with the same facial arrangement.
When I looked closely at an adult photo, in the same year, the pattern repeated.
In 2016 I found the same quizzical look. Potentially, all of these adult photos could be of the same bird, since the pictures were taken in the Arboretum. However, it does seem unlikely that I might have repeatedly photographed only one of a pair of reproducing adults.
Plus, I know that in the case of hatch-year birds the comparison from one year to the next must be of different individuals. So, this 2016 hatch-year photo represents at least the third Barred Owl with the same type of asymmetry.
In addition, this photo shows two different young in that year, so that increases my tally to at least four different individuals.
I also found a 2017 photograph which displayed a Barred Owl with a similar pattern.
Finally, here is a Barred Owl photographed last year in Interlaken Park which shows a similar facial arrangement. This repetitive pattern implies to me that, as a species, Barred Owls have asymmetrical facial disks. Not only am I unable to use this feature to identify an individual adult, but I find it incredibly humorous and humbling that I have photographed these birds for years without being conscious of this consistently quizzical look.
The obvious next question was, Why are their faces asymmetrical? I remember Dennis Paulson teaching us, in our Master Birder Class, that some owls have asymmetrical ear alignments. With ears at different heights, owls can determine more precisely both the vertical and horizontal location of their prey.
I did not remember whether the ears of Barred Owls ears were aligned symmetrically or not. Looking online, I found the following posting regarding:
from The International Owl Center, in Minnesota, which confirmed some asymmetry in Barred Owl ear locations. (If you follow the link above, you can then scroll down to the third photo to read about the Barred Owl ears.) My best guess is that Barred Owl's asymmetrical faces are a functional reflection of and correlation with their ears being at different heights.
After another internet search, I found a post which gives even more details about owls and their specialized hearing. Plus, the commentary gives me the impression that the author shares my belief that the asymmetrical shape of Barred Owl faces is related to the location of their ears.
I doubt that I will ever look at a Barred Owl again, without smiling at their oddly quizzical look.
Wood Duck Update:
In a perfect follow up to last week's post, my friend David G Olsen, sent in his photo of female Wood Duck inspecting Box #9 on the south side of Union Bay. This March 2nd photo is our first recorded box inspection by a Wood Duck in 2019. The hen is clearly intent on kicking off the 2019 breeding season. Way to go, David! Thank you!
Additional signs of Spring, seen this week, include Mallards mating and Bald Eagles and Crows gathering sticks for their respective nests.
What type of tree produces this cone? Is the tree native to Union Bay?
Western Red Cedar: Yes. It is native to Union Bay and the western side of the Cascades.
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