Breeding Habits of the Pied-Billed Grebe in an Impounded Coastal Marsh in Louisiana

ALTHOUGH the Pied-billed Grebe (Podilymbus podiceps) is a common winter visitor in Louisiana (G. H. Lowery, Louisiana birds, Baton Rouge, Louisiana State Univ. Press, 1960; p. 104), only a few remain through the summer and nest. Breeding of the species in Louisiana has been recorded mostly in the interior, although R. J. Newman (Aud. Field Notes, 9: 383, 1955) reported a nest in a large impounded freshwater marsh on Lacassine National Wildlife Refuge near the coast. In the spring of 1961, I found Pied-billed Grebes nesting in a small impoundment of brackish water on Rockefeller Wildlife Refuge. Virtually all previous reports of the nesting of this species refer to fresh water, although R. A. Miller (Cassinia, 32: 25, 1942), writing of the Philadelphia region, has already expressed the thought that the birds might nest under saline conditions where deep water without tidal fluctuation was found. Because nesting of this species has so seldom been noted along the Louisiana coast, and in view of the absence of previous records of nesting in brackish water, in Louisiana or elsewhere, I undertook this study, in which special attention was paid to breeding habits and success.