Species: A. collaris
The ring-necked duck is a medium sized duck in which both sexes have a distinctive bill that has white ring at its base followed by a gray stretch followed by another white ring and a black tip. The males have a black head that has a faint iridescent sheen on it when seen the right way, with golden eyes and a brown ring around their necks. They have light gray to white on their sides, flanks, and bellies. Females are not as strikingly colored as the males. They are generally a brown gray with a dark brown cap on their heads running from the supercillium to the crown to the back of the neck with a pale eye ring and a white chin. The juveniles are similar in coloration to their adult sexes, they just tend to be lighter colored (Hohman et. al. 2012, Ring-Necked Duck. 2016)
Males are only slightly larger than the females, with males weighing 542 to 910 grams, and being anywhere from 40 to 46 cm in length. The the females on the other hand can weigh from 490 to 894 grams and are typically 39 to 43 cm long (Hohman, et. al. 2012).