Brown Booby
Sula leucogaster
The booby's head and upper body (back) is covered in dark brown to blackish plumage, with the remainder (belly) being a contrasting white. The bare-part colours vary geographically, but not seasonally. The species also displays sexual dimorphism of the bare part colours, the males having a blue orbital ring, as opposed to the yellow orbital ring of the female. Female boobies reach about 80 centimetres (31 in) in length; their wingspans measure up to 150 cm (4.9 ft), and they can weigh up to 1,300 g (2.9 lb).
ID text from Wikipedia, CC BY-SA 4.0
Peruvian Booby
Sula variegata
The Peruvian booby has brown upperparts and a white head and underparts. There is noticeable white mottling on the upper side of the wings. Their wing-coverts are tipped white, creating a scale-like pattern. They have a long, pointed, grey bill and grey webbed feet. This differentiates them from characteristic coloring of the blue-footed and red-footed boobies. Female boobies tend to be larger than their male counterparts: their bodies an average of 19% heavier, and their wings 4% larger. Voice: Female Peruvian boobies have a range of vocalizations; from trumpet-like quacks to honks. The male booby, on the other hand, tends to whistle. This kind of auditory communication is unique to adult members of the species, as it takes a few years to be able to produce such vocalizations.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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