Who Is Preying?

No, this is not a religious post about petitioning the Lord...it's about battles for food and survival. Each day I take a walk or two in the surrounding woods, following twisting and sinuous paths that I've forged over the years around trees and other obstacles. I'm always accompanied by the two dogs—one entering the twilight of her years and the other one young and very energetic. In latter’s dashes off into the forest after one critter or another, I've estimated that he manages to cover about 5-6 times the ground I do. The older dog—wise to winding ways of the paths—cuts off a lot of extra loops and manages to return home having traveled about half the distance that I do. To each his own.

A few days ago, strolling near dusk, I watched the junior hound suddenly bolt ahead, in hot pursuit of something. I saw him flush a large bird into the air and noticed a critter scooting up a tree. He loves to chase squirrels up into the over-story branches and bark excitedly at them, as if he might call them back down to resume the chase. He never succeeds at it. This critter seemed larger than a squirrel, however.

As I neared the scene of the action, I saw that it was a raccoon, now some 30 feet up the trunk of a large tree. Then my eye caught sight of the bird. It was a barred owl. It is one of the largest owls we have around here—a few inches shy of two feet long. I watched it silently swoop from one tree to another—not being inclined to fly away, which surprised me, because they are quite shy.

Then I saw the owl head for the raccoon and whap it with its talons as it flew by. A second owl appeared (its mate?) and the two of them dove several more times at the coon, before they settled on a branch and transformed themselves into statues. With no more action forthcoming and not wanting to disrupt a natural event, I headed on down the trail—leaving the drama to play out as Mother Nature wished.

I returned later along the same path and paused to see what may have happened, but neither owls nor raccoon could I spot. As I moved off, I could hear a faint plaintive call from farther back in the woods—sounding more like an animal in distress than a bird call. Was it an injured coon, wailing over its wounds, I wondered, or just my imagination?

What was going on? Returning home, I did a little research to try to discern who might be preying on whom. Barred owls mostly go after small mammals, and I'd not consider a raccoon to be small—not like the mice or rabbits that owls prefer. So I doubt that the owls were preying on the coon.

Raccoons prey on many things, including invertebrates (worms and bugs), plants, and vertebrates (fish and frogs). But good old Wikipedia says they also go for bird eggs! Could that coon had been trying to raid the owls' nest for a couple of tasty and nutritious eggs? This is the time of the year (late April) that barred owls have mated and may well have a few eggs about to hatch. The action I observed may have been mom and pop driving off a predator trying to dine on their unhatched babies.

Maybe I don't want to know who was the predator and who was the prey. I don't like to think about owls' eggs being eaten or a raccoon being injured. Regardless of what I like or not, Mother Nature, besides being incomparably beautiful, can at times be quite ruthless. Can't have one without the other.

Amazing Owl Ears

Owls are nature’s stealth aircraft—they can fly more quietly than most any bird. Their wing feathers allow their wings to beat and glide through the air so silently that they can swoop down unawares and grab rodents and rabbits for their meals. The leading edges of an owl’s wings are serrated, which reduces eddies of air shed by the wing, and thus the noise.

An owl’s eyes are also amazing organs. They are very large—an owl’s stare from a photograph can be disturbingly intimidating. Their eyes are placed in front of their head—rather than at the sides, as for most birds. This gives an owl stereoscopic vision—excellent depth perception—so it can accurately pounce on its pray. Furthermore, owls use their eyes in the dark.

But an owl’s ears are probably their most incredible sensory organ. The eye of an eagle may be able to pick out dinner morsels a mile or so away, but the ear of the owl is equally impressive. Their large heads and fan-shaped feathers efficiently direct sound to their ear openings—and those openings are asymmetrical on the head. One is slightly higher than the other, which increases their ability to zero in on the location of animal sounds.

But the champion hearer of all is also the largest owl of all: the great gray owl. This bird lives in the far north; in central Canada and up into Alaska. It may be the largest owl in the Americas, but the smaller great horned owl is 50% heavier. Why? In order to keep warm in its frigid environment, the great gray owl puffs up its feathers, insulating its body.

And those ears of the great gray! It can sit on the branch of a tree and hear the sounds of a vole several hundred feet away, under several feet of snow! Think about what that implies about the acuteness of the hearing mechanism of this bird. Snow is a good thermal insulator and a good sound absorber. It does an excellent job of muffling the sounds of a skittering vole—who is comfy and believes itself safe, hidden under a deep snow bank. And what overly confident vole would think that an owl perched a football-field distance away could ever be a threat? There goes another meal for the great gray.

That extraordinary hearing capability of this owl implies yet another remarkable fact: the environment must be exceptionally quiet in that far frozen north. Even the slightest background noise—a gentle breeze wafting or any sound from another animal—would prevent the owl from picking out that buried vole. That silence is precious to the owl. It never gets that quiet in the States. The great gray owl had better remain in its isolated north country.