Two hens



In several duck species males have a vivid colouration meanwhile females are brown. As they go in pairs the male solves the problem of identification and the female goes unnoticed. So when females are found alone we realize we did not pay due attention to them. 
Both in water or flying they show identification keys.
Standing or in water with folded wings both have white spots on the face, a green speculum (not always seen), rosy legs and as it was said an overall brown colour, but....
Ringed Teal
Callonetta leucophrys
Ringed Teal
09-02-14 © J. Simón Tagtachian
35 cm
white brow
white line from auricular zone to neck
white throat and front neck
barred flanks
clearer rosy legs
Brazilian Teal
Amazonetta brasiliensis
Brazilian Teal
22-04-15 © J. Simón Tagtachian
38 cm
white spot in front of eye
white spot on bill base
white throat
flanks with a few mottles
rosy legs

In flight or with opened wings designs make them unmistakable.
Ringed Teal
Callonetta leucophrys
Ringed Teal
02-02-12 © J. Simón Tagtachian
circular white patch
Brazilian Teal
Amazonetta brasiliensis
Brazilian Teal
09-07-18 © J. Simón Tagtachian
green and blue sheen contrasting white triangular zone