The Ring-necked Duck is a small diving duck. Males and females are sexually dimorphic and display different plumages. The Males have peak-shaped shiny black heads with a black neck and back. They have gray on the side and a distinctive white mark in front of the wings and a prominent white ring on the bill that’s useful for identification. Females also have peaked heads, but they are a dull brown. The females have a white stripe behind the bill that is useful for identification.