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180 ly the breeding range extended to Chase Lake, North Dakota, and even to Minnesota. Such an adaptability to the moist, showery atmosphere of Manitoba, to the cold mountain heights of the Yellowstone, to the northern wilds of Great Slave Lake, to the deserts surrounding Great Salt Lake and Pyramid Lake, and to the torridity of Salton Sea, is fortunate for the good of the species; else the peculiar conditions essential to a nesting colony would not afford sites enough for the maintenance of the race.

The species is holding its own faintly well, for while the number of colonies has been steadily decreased by the advancing civilization of the west, the number of birds in some of the colonies is increasing. The pelican requires peculiar conditions for his home. First, there must be an inexhaustible supply of fish. Kind of fish does not seem to matter, for on the muddy lakes of the Canadian prairies he eats pickerel and smaller fry with as great a relish as he does the toothsome trout of the crystal-clear waters of Pyramid and Yellowstone lakes. Second, as the bird cannot walk well the nest must be near the water. Third, the nest must be low to afford easy access to the water, in which the young swim long before they can fly. Fourth, the parents and the young are white, and such conspicuous prey must be protected from terrestrial prowlers by the isolation of an island. Fifth and most important, the island must be remote, to afford privacy. Hence breeding pelicans are restricted to large bodies of water remote (or protected) from man, and containing low-lying islands.

In the Yellowstone, the earliest of the returning pelicans arrive about May 1, but the lake is then usually still covered with ice, and the birds spend their time fishing in the open Yellowstone River. All through May the number steadily increases until there are about seven hundred birds; occasionally one or two wander to other parts of the Park but as a rule they confine themselves to Yellowstone Lake and to the river as far north as Hayden Valley. As soon as the ice disappears, and possibly slightly before, especially if the season is a late one, they resort to Molly Island and begin nesting operations. The first egg appears about May 25 and incubation begins a week later. To be exact, there is little attempt at building a nest, for the eggs, two or three large white ones, are laid within a slightly raised rim of sand and pebbles. The horny knobs on the bills of both sexes are at their prime in late May, but by the middle of June they begin to fall, and before the end of the month all are shed. At the same time the color of bill and pouch and the bare skin about the eyes loses the red tinge of the breeding season, and remains yellow until the following May brings its seasonal change again. The white nuchal crest of the breeding season is also at its prime in May, but is lost some ten days later than the bill-knobs, and replaced by gray on the crown and nape.

Both sexes share in the incubation duties, nest relief taking place near noon each day, and, I have reason to believe, again at midnight. The extreme similarity of the sexes prevents me from knowing whether the incoming birds at noon are males, or even if there is any regularity at all. But I do know that this change affords each day a fine opportunity to observe the wonderful flight of pelicans in large flocks. Often they mount high in air and perform maneuvers marvellous in a bird so large and apparently so clumsy (when seen in our zoo's). Acquaintance with them in their native haunts shows them to be as strong and graceful as their great spread of wing should indicate. I believe that flocks follow the leadership of a wise old female pelican if any of that sex are present, otherwise the most sagacious male.