Mallards are small ducks, same look as rouen. Drake has reddish chest feathers.
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Rouen
The plumage coloring of both the Rouen Drake and the Rouen Hen are identical to that of the Mallard Drake and Mallard Hen: Males have green heads, white collars, black tail feathers, a gray body, and a deep claret breast while the Females are mottled light brown with a black crown and eye-stripes; Both genders also have blue speculum feathers. However, Rouens are brighter in colour and larger in size than Mallards. The Rouen Duckling is identical to the Mallard Duckling in terms of plumage coloring. In North America, two distinct types are bred: the common or production-bred variety that is larger than a Mallard but has a typical duck conformation; and the much larger and squarer standard-bred variety. The production variety normally weighs 68 lbs (2.73.6 kg) while the standard-bred weighs 912 lb (4.15.4 kg).
Mallard
The Mallard is 5665 centimetres (2226 in) long (of which the body makes up around two-thirds), has a wingspan of 8198 centimetres (3239 in),[7] and weighs 0.91.2 kilograms (3242 oz). The breeding male is unmistakable, with a bright bottle-green head, black rear end and a yellowish orange (can also contain some red) bill tipped with black (as opposed to the black/orange bill in females). It has a white collar which demarcates the head from the purple-tinged brown breast, grey brown wings, and a pale grey belly. The dark tail has white borders.[8] The female Mallard is a mottled light brown, like most female dabbling ducks, and has buff cheeks, eyebrow, throat and neck with a darker crown and eye-stripe.[8] However, both the female and male Mallards have distinct purple speculum edged with white, prominent in flight or at rest (though temporarily shed during the annual summer moult). Upon hatching, the plumage coloring of the duckling is yellow on the underside and face (with streaks by the eyes) and black on the backside (with some yellow spots) all the way to the top and back of the head. Its legs and bill are also black. As it nears a month in age, the duckling's plumage will start becoming drab, looking more like the female (though its plumage is more streaked), and its wings will start to grow for flight.[8] Two months after hatching, the fledgling period has ended and the duckling is now a juvenile. Its bill and legs will lose their dark gray coloring and its wings are halfway developed for full flight. Its sex can finally be distinguished by three factors:[citation needed]
* Bill coloring: Yellow for males, Black and orange for females
* Breast Feathers: Reddish-brown for males, Brown for females
* Tail feathers: Curled for males, Straight for females
