Other observers have reported avocets as feeding on grasshoppers, predaceous diving beetles, crickets, centipedes, weevils, small snails, sea slugs, small crustaceans, and even small fishes.
Behavior.—Avocets are at all times tame and unsuspicious, very solicitous and aggressive on their breeding grounds, quiet and indifferent at other times, showing only mild curiosity. Their demonstrations of anxiety on their nesting grounds, particularly if they have young, are amusing and ludicrous. Utterly regardless of their own safety, they meet the intruder more than half way and stay with him till he leaves. W. Leon Dawson (1909) has described it very graphically, as follows:
The mother bird had flushed at a hundred yards, but seeing our position she flew toward us and dropped into the water some 50 feet away. Here she lifted a black wing in simulation of maimed stiffness, and flopped and floundered away with the aid of the other one. Seeing that the ruse failed, she ventured nearer and repeated the experiment, lifting now one wing and now both in token of utter helplessness. After a while the male joined her, and we had the painful spectacle of a crippled family, whose members were uttering most doleful cries of distress, necessitated apparently by their numerous aches and breaks. Once, for experiment's sake, we followed, and the waders flopped along in manifest delight coaxing us up on shore and making off through the sagebrush with broken legs and useless wings. But we came back, finding it better to let the birds make the advances. The birds were driven to the very limit of frenzy, dancing, wing trailing, swaying, going through last convulsions and beginning over again without regard to logical sequence, all in an agony of effort to divert attention from those precious eggs. As time elapsed, however, the color of the play changed. Finding that the appeal of cupidity was of no avail, the birds appeared to fall back upon the appeal to pity. Decoying was useless, that was plain; so they stood with upraised wings, quivering and moaning, in tenderest supplication. It was too much even for conscious rectitude and we withdrew abashed.
The flight of the avocet is strong, direct and rather swift, much like that of the greater yellow legs, with neck and legs fully extended, fore and aft. It can alight on or rise from the surface of the water with ease. On alighting its long, black and white wings are raised above its back, and slowly folded, as it settles itself with a nodding motion of the head, stands still and looks about it for a moment or two. No bird is better equipped for the amphibious existence that it leads; its long legs and webbed feet enable it to wade through soft muddy shallows of varying depths; and if it suddenly steps beyond its depth it swims as naturally as a duck until it strikes bottom again; the thick plumage of its under parts protects it and marks it as an habitual swimmer. It often feeds while swimming by tipping up like a surface-feeding duck and reaching down into the water with its long neck and bill. It can even dive when necessary.
Dr. Walter P. Taylor (1912) says that avocets "share with most other birds a dislike of owls. Three were seen pursuing a Speotyto over a wild hay meadow."
Dr. T. Gilbert Pearson (1916) noted an interesting flight maneuver:
Only a few weeks ago I was impressed anew with the beauty of these birds. While passing down the valley of Crane Creek, in southeastern Oregon, a flock of about 50 avocets arose and indulged in a series of evolutions which even the most casual observer would have paused to watch. In a fairly compact company they flew away for a short distance, then turned, and, after coming back almost to the starting point, dived toward the earth, arose again perhaps 50 yards in the air, then swung around and came back. These maneuvers were repeated at least three times. Their white and black plumage, flashing against the gray sagebrush of the desert mountain side, and sharply relieved as they skimmed over the alkaline creek, made a picture long to be remembered.
Charles E. H. Aiken (1914)
witnessed a curious performance of avocets in Utah. In September, 1893, he visited the mouth of Bear River where hundreds of acres of mud flats and shallow water offer an attractive resort for various water fowl. In a submerged grove where patches of mud appeared above the water hundreds of avocets were congregated. One little mud island that differed from others in that it was quite round seemed to have a fascination for the birds, and they were packed together upon it in a mass which covered the island to the water's edge. As the island was about 12 feet in circumference the number of birds probably approximated 150. This mass of birds continued to revolve about from left to right, and being so crowded the movement was rather slow and their steps short and measured, so that the impression was that they were all marking time in the marching. Birds on the rim of the circle avoided walking off in the water and crowded inward against the mass. Every moment or two birds would leave the milling body and fly to a neighboring mud island, and as many from near-by would fly to take their places and join the dance. Aiken advanced quietly to within 20 yards and viewed them for half an hour, but they continued undisturbed by his presence and he left them so. It appeared to be a diversion of the birds.