Record supplied by Margaret Ning. Two yellow birds in flock likely with condition of Leucism, a condition in which there is partial loss of pigmentation in an animal resulting in white, pale, or patchy coloration of the skin, hair, feathers, scales or cuticle, but not the eyes. Unlike albinism, it can cause a reduction in multiple types of pigment, not just melanin.
Geoff, could you please amend all your recent bird sightings to be a best estimate abundance to fit in with standard bird survey practices. With birds an estimate is always preferred rather than a range. Thanks, Sandra