Mexican Jay vs Unicolored Jay

Mexican Jay

Aphelocoma wollweberi

Medium113 gForest

The Mexican jay is a medium-large (~120 g) passerine similar in size to most other jays, with a blue head, blue-gray mantle, blue wings and tail, and pale gray breast and underparts. The sexes are morphologically similar, and juveniles differ only in having less blue coloration and, in some populations, a pink/pale (instead of black) bill that progressively becomes more black with age (Brown and Horvath 1989). Some field guides misreport this color as yellow because the pale bill becomes yellow in museum study skins. The iris is brown and legs are black.

ID text from Wikipedia, CC BY-SA 4.0

Photo: EJ Burns · CC BY 4.0

Unicolored Jay

Aphelocoma unicolor

Medium124 gForest

The unicolored jay is about 34 cm (13 in) long. The nominate subspecies A. u. unicolor weighs about 125 to 150 g (4.4 to 5.3 oz). The sexes have the same plumage. The nominate subspecies is entirely deep blue to purplish blue that is somewhat darker on the sides of the head and the throat. Juveniles are a slightly bluish gray that is duller than adult plumage. Subspecies A. u. griscomi has the same plumage as the nominate. A. u. guerrerensis is the most purplish subspecies, A. u. concolor is a paler blue than the nominate, and A. u. oaxacae is somewhat darker than the nominate. Voice: Though recordings of unicolored jay vocalizations come from most of its range, detailed analyses come primarily from the Montebello studies. The birds there made hundreds of variants of their calls though many were only subtly different from each other. The calls were described as grating/harsh, musical/resonant, whistled, loud, and soft.

ID text from Wikipedia, CC BY-SA 4.0

Photo: datadan · CC BY 4.0

Photos and recordings are credited to their authors under the licence shown. Full profiles: Mexican Jay and Unicolored Jay.