Banding Saw Whet Owls at Hueston Woods...wow!

Last Saturday evening I headed over to the Hueston Woods Biological Station with my friends Paul Kruesling and Joe Kappa to watch Northern Saw Whet owls (Aegolius acadicus) being banded by Drs. Jill and Dave Russel with the Avian Research and Education Institute (AREI).  Have you ever seen a Northern Saw Whet owl? Can you say cute...

Northern Saw Whet Owl (Aegolius acadicus) 
Cuter than cute can be, but this little night bird is a lethal hunter and can dispatch prey in one swoop and strike. 

Northern Saw Whet Owls are the smallest owls in eastern North America. They are rarely seen because  during the day, they sleep in conifer tangles, and if they are disturbed by a human tramping past, they do not flush. Their defense is to remain motionless, and it works. Northern Saw Whet Owls posses disruptive coloration (a camouflage pattern consisting of contrasting light and dark patches, spots or stripes), and it works best when the animal is still.

Is that bird tame?
Because Saw Whet Owls' primary defense is to remain motionless, they appear to be tame, but don't be fooled. They really are wild birds (just ask a mouse). Their "tameness" however, is legendary, and researchers report of being able to walk right up to one and pick it up off a branch. The diminutive owl is so calm around humans it appears to have no fear and even seems curious about us!

...those eyes, those fluffy feathers, that tiny little rectangular body....there's no doubt this pint-sized nocturnal hunter graduated from the Institute of Cute, but looks can be deceiving--there's might and fright behind all of that fluff...  

You may wonder how researchers capture these tiny owls. It's pretty cool. They select an area in the woods with dense stands of conifers and set up huge mist nets. The nets are placed near an audio player amplifying the male's territorial song. Every thirty minutes the mist nets are checked to see if an owl has flown into one. If one has, it's gently removed from the net and placed in a soft bag to await banding...

A Northern Saw Whet Owl rests in a soft bag waiting to be banded. We were able to watch Dave band three Saw Whet Owls and one Eastern Screech Owl.

...getting ready to place the band on the owl's leg. 

In addition to banding, researchers gather other data, such as the bird's weight, wing length, tail length, whether it's male or female, its age, and amount of fat deposits. It doesn't take very long to gather all this data and the little owl just watches and studies...

...the tiny bands that will be fastened around the owl's leg were strung like beads on a fine thread. They are very light and the bird doesn't even notice when one is attached. In the background, you can see the black calipers used to take small measurements. I didn't take notes that evening, so I don't remember everything that was measured. I was too busy marveling at the patient little owl. 

A closeup of a Northern Saw Whet Owl's facial disk shows the feathers of the facial disk are different from the feathers elsewhere on its body. Many look soft and fluffy, but others appear barbed or even skeletal. The feathers in the concave disk help direct sound to the ear openings.

As I mentioned earlier, these cute little brown and white owls with gorgeous yellow eyes are ferocious hunters and can kill their prey, often a deer mouse or a white-footed mouse, quickly and easily with their talons after a strike. Since the owls are small they usually only eat half of a mouse, storing the rest until the next meal. Also, if prey is abundant in winter, Saw Whet owls will stock up by stashing uneaten carcasses in tree holes where they remain frozen for future meals. When the owl is ready to eat from the frozen cache, it thaws out the meat by "incubating" it like an egg (source: Penn State, The Virtual Nature Trail, click here).

...the eyes of a Northern Saw Whet Owl look on patiently.

If you look closely, you can see the frayed edges of the owl's wing feathers. This unique adaptation is what gives them their silent flight. The trailing feathers are fringed and tattered and break up the sound waves generated as air flows over the top of the wings and forms downstream wakes (click here for an earlier post about Barn Owls that talks about this adaptation).

It was cold that night, but my giant snow parka kept me warm. The little owl felt like a ball of warm fluff in my hands. She was so gentle and never took her eyes off me. I can't describe how amazing it felt to hold this little wild creature. 

...being a night owl, I really appreciated getting out to see these owls, which are only passing through our area. Every fall, Saw Whets leave the northern forests where they nested and migrate south to their wintering grounds. Most have past through by the beginning of December. 

If you want to learn more about the work being done by the Avian Research and Education Institute, click here. From their website: "AREI is a non-profit organization dedicated to enhancing the preservation of avian populations. Our mission is to protect and conserve avian populations through research, education and advocacy. To this end, AREI is committed to establishing biological stations that will provide bird banding and environmental education to the public."