Alkali Flies

Nature Notes by Dr. Frank Lang

Years ago “Nature Notes” taught his Biological Illustration course at the Malheur Field Station some miles south of “Where the hell is Burns, Oregon” near Steens Mountain. At first glance, the Great Basin may appear a biological wasteland; the impression you might get zooming by at 70 miles an hour. In fact, it is a biodiversity treasure trove. Nature Notes had a chance to visit Stinking Lake west of Harney Lake, west of Malheur Lake sometime in the 1970s. You need special permission to go there.

Malheur is fresh water, with alien carp the size of Jaws. Harney and Stinking Lake are alkali lakes, dried up, very salty leftovers from the great Pluvial lake of Pleistocene days. No carp in alkali lakes, but still lots of wildlife. I remember bouncing along a narrow track west of Malheur Lake engulfed in clouds of alkali dust whether or not we were in a low spot in the road. When we got to Stinking Lake, we were engulfed by something else beside the smell. Clouds of small black files, knee high, were loudly buzzing on the white salty shore along the edge of the water. They were alkali or brine flies common at alkali lakes in the west, but best known and studied at Mono Lake in California.

Alkali flies and shorebirds have, to my mind, a wonderful ecological relationship. The flies’ lifecycle, like that of the Pandora Moth, is complete, with adults, eggs, larvae, and pupae. Flies eat algae, mate, lay eggs in water, which hatch into aquatic larvae that eat mostly algae and bacteria. The larvae eventually pupate after under going a series of morphological and biochemical changes storing nutrients in the process. Pupae pupate and adults emerge. All this is done in enormous numbers. These numbers are noticed by birds like snowy plovers, avocets, black-necked stilts, at Stinking Lake and gulls, eared grebes and Wilson’s and red-necked phalaropes, at Mono Lake. Other species also take advantage of the energy rich feast of fat and protein provide by the flies. Birds enhance the algae’s nutrient supply by pooping in the soup, so to speak, to algae’s and the flies’ benefit.

Early European explorers of the inter-mountain west write of finding windrows of larvae and pupae cast upon the shores of alkali lakes by wind and waves that might extend for several miles like a rim around the lake. One explorer estimated hundreds or thousands of tons of larvae and pupae, live and dead, in drifts available for the taking.

Native Americans in the area did not hesitate to take advantage of these nutrient rich resources by collecting, drying, saving, then cooking and eating the flies throughout the winter. When thoroughly dry, the insects were ground into a meal, then mixed with other foods like acorns and berries then made into a bread, or just mixed with water and hot stones to make a soup. The Indian name of the Mono Lake Paiute tribe is Kootz-a’-di-ka-a’, means “fly eater.”

So, are you sitting there smugly thinking I don’t eat insects, won’t eat insects? When was the last time you ate peanut butter? Food and Drug Administration says an average of 30 or more insect fragments per 100 grams is bad. But not to worry though, the significance is only aesthetic.

— Dr. Frank Lang

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