Nebraska Ornithologists' Union


Date of this Version



The Nebraska Bird Review Vol. 85 No. 2 (2017), pp 83-84


Published by the Nebraska Ornithologists’ Union, Inc.


On 9 March 2017 at 0805 hrs, two A. canadensis tabida were observed copulating on a sandy island within the south channel of the Platte River, Hall County, Nebraska (40.790982°N, -98.404635°W, WGS84; 581 m elev.). Two biologists witnessed the copulation at a distance of about 175 m looking to the south from within an overnight viewing blind on the north bank of the south channel of the Platte River, utilizing an 80 mm spotting scope (20x60x magnification). The sequence of events previous to the copulation followed very closely the observations reported by Tacha (1988). The copulation was proceeded by the male holding the “bill up” display pointing its neck and bill in a straight line at approximately 45° to the body (Tacha 1988). The male initiated this behavior and held it longer, but the female also completed a “bill up” display previous to copulation. The male then paced around the female, she flattened her back and opened her wings partially, providing a spot for the male to land on top of her and place his feet atop her scapulars. Following this, the pair made a series of cloacal contacts with mounting lasting approximately 8 to 10 seconds.