I knew I was blessed when I spied a Northern Flicker in the backyard early this morning. This is the one woodpecker that doesn’t behave like a typical family member for it forages on the ground rather than a tree trunk.
From the kitchen window, I watched this guy for a while as he looked for food. I knew it was a male because of the so called black mustache on either side of its bill. But . . . it was the bird’s eyes I was most curious about . . .and their placement on the side of its head.
Like mammals, birds with eyes on the side are born to hide . . . from predators. His field of vision, therefore, was wide and the ants on the ground were the ones who needed to scurry and hide.
After dining for a while, the flicker flew off and I stepped out the door–in search of other sets of eyes to behold–like the red ones of a tachinid fly,
and metallic green on a long-legged fly. Like the flicker, flies also have a wide field of vision due to the fact that they have compound eyes. Each eye consists of thousands of individual visual receptors, or ommatidia, (singular ommatidium) (om·ma·tid·i·um, äməˈtidēəm.) Each hexagonal-shaped ommatidium (think honeycomb) is a functioning eye in itself. With thousands of eyes on the world, it’s no wonder flies and other insects see us coming–especially when we have a flyswatter in hand.
I kept looking and among the elderberry shrub leaves I found a strikingly beautiful green and brown stink bug, or shield bug, if you’re looking for a more pleasant name. Like all insects, it featured those compound eyes, but I was struck by how tiny they were. Apparently, it was enough to see movement and kept trying to hide from me.
Despite its efforts, I could zero in on it even after walking away and returning.
Eventually I moved my focus to Pondicherry Park, where a variety of eyes greeted me, including those of a Song Sparrow.
What did he seek? Insects and other invertebrates, such as weevils, leaf beetles, ground beetles, caterpillars, dragonflies, grasshoppers, midges, craneflies, spiders, snails, and earthworms.
What about a slug? I suspected the sparrow would enjoy such and today was a decent slug-like kind of day. But, how does a slug see?
A slug has two pairs of retractable tentacles on its head. The upper, optic tentacles, feature light-sensitive eyespots on the ends. And just like a deer can move each ear independent of the other, slugs can do the same with each eye-stalk. Another cool fact: an eye stalk can be re-grown if something attacks it.
Further along, I found a wolf spider hanging out on last year’s fertile frond of a sensitive fern. Did you know that spiders have eight legs AND eight eyes? Two of them are large and prominent–the better to see you with.
As I continued to look for the sparrow’s prey, I discovered an ebony jewelwing that I determined had just emerged for it posed as I took numerous photographs. Usually, they flit about like woodland fairies. Unlike its larger dragonfly cousins who have eyes in front in order to hunt, the damsels’ are on the sides. Though zoom-and-swoop attacks may not be possible for the damselfly, it can see all-round–including above and behind– giving it control of its airspace.
My wander continued and then I heard a sound and saw some action in a tree about thirty feet off trail. And just like that, in what felt like a miracle of miracles, I realized I was in the presence of the wise one.
With his eyes in front, a Barred Owl is born to hunt. For several minutes we starred at each other and I was honored by his presence. Of course, I hoped he might cook for me tonight, but he let me down. Possibly he had others more in need of supper than I was at the time.
In the end my vote was aye in favor of all the peepers I’d met along the way, both in the yard and the forested park, for I knew that the eyes had it.