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Ornithology class learning about mist netting and banding birds. Student learning safe method to hold birds (bird waiting its turn to be banded). Video of teacher demonstrating: https://flic.kr/p/2pryszc

Albino individual of black vulture (Coragyps atratus) next to two other vultures with normal coloration. Note the radical contrast in coloration and the absence of melanin in the retina.

Address: Nosara beach, Nicoya, provincia de Guanacaste, Costa Rica.

Recorded date: 2019/03/25

Credits: José Venegas

An asymmetric replacement pattern in primary coverts.
EXPLANATION 1:
RIGHT WING: looks consistent with a TCB (two retained juvenile pp covs, outer and inner block of replaced 2nd cycle pp covs, and middle block of replaced 3rd cycle pp covs).
LEFT WING: Middle block of 3 retained juvenile pp covs, with outer and inner block of 2nd basic pp covs. It's possible that 1 or 2 middle pp covs among the outer block are 3rd cycle.
EXPLANATION 2: both wings show only 2 generations of pp covs, with both being "adult", making this a M-TCB.

This bird was first captured a year earlier in April 2010 with a vascularized brood patch and a note of "2 generations of pp covs," but we appear not to have photos. This capture history confirms the bird is M-TCB in May 2011.