188 VoL. XII NESTING NOTES ON THE AMERICAN EARED GREBE AND PIED- BILLED GREBE By ROBI?3RT B. ROCKVE1, L WITH FIVE PHOTOS BY THE AUTHOR T WOULD be difficult indeed to name a family of common North Amer- ican birds which presents more unusual peculiarities in habits and structure than does the grebe family. Queer in structure, almost helpless on land, never leaving the water except during migration, and bilding a floating nest upon the water, where the eggs are hatcht largely by the aid of the sun's rays, these peculiar little spirits of the water present a very radical departure from what the word "bird" usually brings to mind. This is particularly true in a semi-arid country Fig. 59. NEST AND EGGS OF AMERICAN EARED GREBE.' A FLAT STRAGGLING AFFAIR OF FLIMSY CONSTRUCTION such as Colorado, where suitable habitats are scarce and where the few families of similar birds are not found. It was therefore with a great deal of interest that, in company with Mr. L. J. Hersey, I studied the habits of the?e birds for three summers among the Barr Lakes near Denver. The first birds made their appearance about the middle of April (April 14 is my earliest record) but did not become common until shortly after May 1. The ear- liest nests were noted May 10 (1907) and 11 (1908), nests of the American Eared ( Colymbus n. californicus) and Pied-billed (Podilymbus podiceps) Grebes being equally abundant; but as the seasoul advanced we found that the Pied-billed Grebes were nesting in far greater numbers than were their cousins. The Eared Grebes' nests were easily distinguishable by the flimsy and ap- parently careless manner in which they were constructed, being very slight, strag-
