Naturalist's Notebook Archive

Naturalist's Notebook No. 2

Death of a Hornet
by Don Kirk

Two male black-chinned hummingbirds are squabbling over property that belongs to neither bird. The argument is short and noisy, the hummers briefly circling each other in tight maneuvers, while emitting many high-pitched chirps. One male leaves, and the other perches on a twig of the water birch. With a green back and head, a black throat above a violet purple stripe, and white under parts, this small bird is indeed handsome. It is early August and the hummer is through with nesting and spends much time feeding.

Abruptly, the bird leaves the perch and hovers at the source of the dispute -- freshly drilled sapsucker holes in the bark of the water birch. Although the holes are quite fresh, the sapsucker is not in view.

I settle myself comfortably in the deep shade of a neighboring water birch to do a little feeding (my lunch) of my own. Drinking the birch sap oozing from the sapsucker holes is clearly a normal thing for these hummingbirds to do, and it shows some of the complex relationships among living things.

Peering out from under my water birch, I see several different biotic communities of plants and animals arranged in orderly patterns over the land. This arrangement is influenced by soil characteristics, water supply and exposure. My family and I are camping on the steep eastern slope of a wildly beautiful mountain range nearly on the border between Nevada and Utah. Great Basin mountains are truly islands of peace, and repose encircled by oceans of sagebrush, rabbit brush, salt bush, shadscale and grass.

Near our camp a spring trickles into the rushing creek. Along the creek and around the spring thickets of water birch 10 to 12 feet tall share the crowded space with aspen, willow, grass, red currants, and many wildflowers. Such a lush habitat is supportive of much wildlife. Since our arrival I have seen deer, skunks, chipmunks, cottontail rabbits, coyotes, deer mice, wood rats, long tailed weasels, and a rattlesnake. Birds are numerous and, along with the hummers and red-naped sapsucker already mentioned, house wrens, red-shafted flickers, dark-eyed juncos, western tanagers, Brewer’s sparrows, mountain bluebirds, robins, and others.

Forty to fifty yards on either side of the creek the plant cover changes sharply. The steep slopes of the canyon support piñon pine, juniper, mountain mahogany, sagebrush and two species of cactus. Downhill, toward the desert valley, the piñon and juniper give way to sagebrush, and out on the arid flats far below shadscale dominates.

Uphill from camp a peak rises to more than 13,000 feet. Upon its rugged sides this creek and canyon originate. A hike of a mile or two upstream takes one into fir, ponderosa and abundant aspen. Near timberline are stands of bristlecone pine. Above that are vast expanses of lichen covered, broken rock.

My thoughts are interrupted by the arrival of the owner of the feeding station, a red-naped sapsucker. Landing on top of the thick water birch branch, the eight-inch long bird effortlessly scoots around the limb to hang upside down and peck vigorously at the holes in the red-gray bark. Running its beak around inside a hole, the sapsucker laps up the sticky juice found there.

Meanwhile, the black-chinned hummingbird perches on a nearby twig, the feathers on the top of his head raised slightly. A fly lands on his green back, and he bursts into flight, furiously stabbing at the offending insect, nearly spearing it. Landing again on the same perch, the hummer resumes his vigil. The sapsucker departs seemingly unconcerned that others are dining at its table. The hummingbird remains perched and my attention returns to the holes in the birch bark.

In the absence of the birds, other animals take their turn at the sap lick. Most numerous are the flies buzzing about in apparently aimless fashion. Landing on everything, living or dead, they annoy all of us, myself included. Next in number are the ants. A wood nymph butterfly appears and delicately walks among the flies crowding the weeping holes. The hummingbird returns to the sap-lick. A big yellow hornet settles near a crowded, sap-filled cavity and begins to feed.

Although the fluid in the hornet’s saplick seems plentiful, the yellow and brown insect apparently decides to claim the whole area as its own. Buzzing its wings and zooming at the flies and butterflies the hornet quickly clears the branch of most competitors. Even the ants vacate the near vicinity of the stinging creature. Amazingly, after a short aerial battle with the hornet the hummer retreats to a nearby water birch. The hornet is sovereign.

Abruptly, the hummer decides to lap at the sap and settles at the hole farthest from the hornet, but it is still too close to the bullying insect. The hornet zooms at the small bird, which dodges to one side and then stabs at the huge stinging wasp. With surprising speed and agility the hornet avoids the hummer’s jab and strikes at the head of the bird. This seems to be too much for the hummingbird, and it vacates the fight for its favorite perch in an adjacent water birch. Triumphant, the insect reclaims its territory.

Shortly, the sapsucker returns, gobbles a few ants and hops along the branch toward the hornet. Obviously aware of the hornet’s potential the sapsucker feints at the insect. Vigorously vibrating its wings as if in warning, the hornet remains feeding, and pays the ultimate price for its greed and obstinacy. In a lightning move with the tip of its beak, the sapsucker grasps the hornet in the middle of its body. A quick jerk of the bird’s head, and the insect’s body is severed, the twitching pieces falling to the ground.

Away flies the sapsucker on another round of its territory. Back to the saplick troop the insects, minus the hornet. The hummingbird returns, squabbles with other hummers, drinks a little sap, temporarily drives off a few flies, then departs for its perch. The flies feed, butterflies arrive and feed, the ants feed. Eventually the sapsucker returns, scares off some flies, ignores the butterflies, eats a bunch of ants, drinks some water birch sap and takes off again.

High drama in the bushes, this sort of thing occurs millions of times a day in the global ecosystem of Planet Earth. On land, in the air and under water, birth, death, feeding, resting, and the recycling of materials happens again and again.

Somewhere on the ground pieces of the hornet will be devoured by something and turned into a tiny bit of humus to help enrich the soil. The water birch will grow high and spreading, thrusting its dark green toothed leaves to the energy-giving sun. By means of photosynthesis energy will be stored in the shrub’s body. Some of it will be used to manufacture more sap, which will provide another sapsucker the energy to drill more holes, and insects and hummingbirds will continue to benefit.

Undisturbed, and taken together, the multitude of these kinds of relationships will provide the world’s living things, including humans, with sufficient food, water, and shelter.