This is a subject I have had an interest in over some years. It began with the use of flash on the bowerbird in the field, which almost invariably produced an eye of a startling electric blue colour. This was in marked contrast to the
HANZAB illustrations which showed an iris colour which, for want of a better word, I shall call apricot. It was also in contrast with the description of ‘bare parts – based on photos’. This began, for the adult male, ‘Iris, purple (c172B) or deep mauve (dark
172C) …’ The references are to the Smithe ‘Naturalist’s Color Guide’. It is a hazardous undertaking to convey colours by digital image but I attach an approximation based on a scan. Various factors including your monitor settings will determine whether
you see anything like what I see.
I then put the subject to one side because of the notorious unreliability of flash in showing ‘true’ colour, particularly in relation to eyes. I was prepared to accept ‘purple or deep mauve’ as an accurate description – notwithstanding
that it was based on photos of others.
However, recently with the ready availability of subjects in my garden I have sought SBB images without reliance on flash, using where necessary a high gain setting and applying digital brightening later. The results were very like what
I had obtained earlier with flash - although rather different from the dark (might I say nondescript?) eye colour you might see with your own eye (with or without binoculars).
As a result of examining hundreds of SBB images obtained over several years, I shall now offer some conclusions.
