Mallards (Anas platyrhynchos) are the best-known dabbling duck, occurring in puddles, ponds, and marshes on several continents. They are highly gregarious and in urban areas, “duck ponds” may be filled with “mallards on the dole” waiting at the edge of ponds for children of all ages to throw them pieces of bread. But the Mallard of the marshes is a wild duck, wary of humans and other potential predators. More than 10 million Mallards occur in North America, and they have spread throughout the world with millions more in Eurasia, Africa and South and Central America. They are a highly successful invasive species in New Zealand where now, the mallard is the most abundant New Zealand duck. DNA analyses have shown that mallards, along with Muscovy ducks (Carina moschata) are the ancestors of all domestic ducks. Mallards freely interbreed with domestic ducks forming “sports” with a bewildering variety of colorations. They also are able to breed with other Anas species such as the American Black Duck and the Northern Pintail. Most offspring from these crosses are fully fertile. Mallards probably evolved relatively recently – during the Pleistocene period (126,000 – 10,000 years before present) when North America was intermittently covered with huge glaciers. Mallards are monogamous and soon after ducks arrive in their winter homes, courtship begins, and pairs are formed. In the spring, pairs head north to the place of the female’s origin to begin nesting. Both the male and female build a simple nest on the ground very close to the water’s edge. The female then lays 8-13 eggs and begins to incubate the eggs for 28-28 days. Once incubation begins, the male leaves the female, joins other males and undergoes his annual molt. Once all chicks hatch, the female leads them into the water, and they never return to their nest. The chick’s feathers are not waterproofed and so the female must preen each to provide them waterproofing. The chicks are precocial – that is, they are able to swim and feed immediately upon hatching. Like the adults, they feed on worms, snails, arthropods, aquatic and terrestrial insects and seeds and other plant matter. Most mallard hens are able to breed as yearlings though young hens experience high chick mortality. The best mothers are the old hens who have high chick survival.