Everyone knows the mallard, but what about its nearly genetically identical cousin species, the black duck? Also known as “dusky ducks” or “blackjack,” these ducks are one of the last quackers to migrate for the winter, hanging around in cottage country even until late November.
Black ducks are dabblers, not divers. They feed by skimming their bills along the top of the water, or tipping forward to dip their heads below the surface, and—bottoms up!—popping their butts into the air. (Diving ducks, on the other hand, plunge completely into the water to feed.) A black duck’s beak is super-sensitive, with 28 nerve endings per square millimetre. That’s eight more per square millimetre than a human finger.
Mallards and black ducks evolved into separate species during the last Ice Age. But males still share the same courting behaviours—lots of tail shaking, whistling, and flicking the ladies with water—and the two birds do sometimes interbreed, producing hybrid offspring that look a little more like mallards.