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Kodiak Alaska Military History



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THE NATURALIST
by Dave Evans

Bird Escort
July 30, 2001

My wife and I walked the beach the other afternoon, and as we proceeded through the grass to the sand, a robin-sized bird flew up, circled us twice, and landed on some driftwood about twenty feet away, calling with a plaintive two-syllable cry. The bird was brown on top and white on the bottom, with a single handsome black ring around its neck. It proceeded to run ahead of us on its long legs everywhere we walked, occasionally taking flight for some of its close-range circling.

We began to get the impression that we were being led around the beach. The cry started sounding more like "Come HERE!" to me. Indeed, when we left the beach, the bird ran ahead of us, escorting us all the way along about two hundred feet of pathway. Then it took off and arrowed back to the beach area where we'd first encountered it.

The bird was a semipalmated plover, a reasonably common Kodiak summer resident. It makes its nest in grassy areas just before the shoreline, and forages for insects in the grass or for small marine organisms along the shore. In winter the plovers migrate south, as far as South American coastal regions.

I'd been familiar with another bird, the killdeer, that calls attention to itself, producing a realistic broken wing display when it feels the nest is threatened. This type of behavior is called a distraction display, and is most likely to be seen in shore birds and some other ground nesters. Some displays are extreme. One species, in the "rodent run," scurries stooped on its legs, dragging its wings in semblance of a second pair of legs, while making un-birdlike squeals.

I've gone down to the beach alone several times since then, and the plover appears on cue, though I don't get the full escort treatment my wife and I received. Perhaps two potential predators produce a more exaggerated form of the behavior. Distraction displays also seem to lose intensity if repeated visits by a possible predator result in no threat to the nest.

These plover encounters got me thinking about other deceptive signals seen in the animal world. From our plover, we got a "follow me" signal, presumably misdirecting us with bad information that resulted in our being lured away from a nest among the grasses. If I were a plover predator, the mother bird incurred some little risk, with the consequence to me being a missed plover hatchling meal.

Another example in which the result is a missed meal is behavior of a tropical tanager shrike. When it sees another bird pursuing an insect, it emits a predator alarm cry. As the other bird responds to the ruse by taking cover, the false alarm caller grabs the sought-after insect. Consequences are more severe for some other receivers of bad information. A predatory firefly can mimic the flashing mating signals of females of its prey firefly species. Amorous males, seeing the flash below them, dive into the grass to find themselves in a situation both unexpected and unpleasant. Angler fish use a somewhat similar strategy--based on eating rather than mating--of attracting prey fish by wriggling a lure held just above the mouth of the predatory angler.

Humans, of course, are accomplished at giving out bad information when situations call for it. During World War II, camouflage based on misdirection became an art form. Inflatable rubber tanks and aircraft were positioned in conspicuous areas far removed from the real targets. One of my childhood memories of wartime Los Angeles is driving with my parents under the camouflage netting covering streets around the Lockheed aircraft factory and looking up to see a whole false landscape of houses, farms and fields constructed on the netting itself.

Kodiak apparently had its own distraction display at that time. This, of course, was our "False Village," a set of lighted window frames to deceive aircraft at night. Presumably attacking aircraft would fly by the blacked out Real Kodiak and use the False Kodiak as their guideline for bomb runs on the Navy Base at Women's Bay. The result of the misdirection would be a tremendously cratered Saltery Cove Road (almost indistinguishable from what exists today, come to think of it). We've been unable to pinpoint exactly where this camouflage effort was located--most discussions have it somewhere along Middle Bay, though there are other possibilities. We think it did exist, or, if it didn't exist, it certainly should have. (If anyone in the reading audience has some specifics on False Kodiak, please give me a call at Fort Abercrombie!)

A number of examples of misdirection by giving bad information appear among the animal world, but it may be that our human species is the one that most successfully capitalizes on the technique as both a survival and a social strategy.


http://www.kadiak.org/naturalist/bird_escort.html Updated 2001 August 20

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