General Description: Common Mergansers (Mergus merganser) are sexually dimorphic pond "ducks" with a long, thin bill. Males have an iridescent green head and black back, and the neck, breast, and sides are white. Males do not have a crest. Females have a rusty head and white throat, clean white breast, gray body, and a shaggy crest (it is always a bad hair day for lady mergansers).

Favored Habitat: Ponds and marshes; places with fish to eat.

Where to Find: Common Mergansers are fairly common around Las Vegas; look for them at the Henderson Bird Viewing Preserve, Lake Mead, the Pahranagat Valley and the Overton Wildlife Management Area.

Comments: These birds dive for fish, which they catch in their long, saw-tooth-edged bill.