Anthea
I am erring on the side of caution now. I'm not saying that Regent
Honeyeaters do not change face colour but merely that I haven't seen it
(and I suppose I have had a lot of experience with this species). They
definitely do not, however, have the ability to "flush" as do Jacanas and
Figbirds where there is a change in soft parts over a short time frame.
There is a note by Franklin & Menkhorst (Aust. Bird Watcher 12 (7)
September 1988) on the colour of the facial patch that does suggest that
some birds have a pink face. I'm not sure if this is all a matter of
subjective interpretation or not - one mans "pink-buff" is another's
"yellowish" - although some observers have reported different face colours
within birds of the same flock. Again I have not seen anything myself
along these lines.
(It's just been bought to my attention that the close-up of the head of a
Regent Honeyeater in the Recovery Efforts brochure shows a bird with a pink
ring around the eye. The warts I would still class as being yellow. This
is perhaps as pink as I have seen them. Maybe I'm too familiar with the
little sods!).
There was a tentative suggestion that face colour may change with age.
Along these lines, I think that older birds get "wartier" with age. Warts
start to develop at about 9 months of age (prior to this the facial skin is
bare) and the warty face is fully developed at about 12 months. Some birds
have extremely warty faces with warts extending above the eye, these birds
often have much more yellow in the wings as well. I have a measure of
"wartiness" for birds that I catch that with time, and the recapture of
individuals, might determine whether this is so. The facial colour of
these "very warty" birds is still yellowish.
Perhaps what I need to do is issue a colour chart to all banders of Regent
Honeyeaters to facilitate the description of facial colour rather than
using a more subjective method. We need to think, however, about what is
being gained from such an exercise. Are we merely settling an interesting
question or is there a real benefit for the recovery effort of this
endangered species? Perhaps there is if this could be used as an easy
guide to breeding condition (which I personally doubt) or a guide to the
ageing of the bird. The latter could be of importance in sorting out the
demographics of certain populations - is the population ageing or are young
birds being successfully recruited into the population?
I guess this latter question all comes down to why people collect certain
bits of information. Is it just because that is what they were trained to
do and thus automatically do it without really thinking about why? What is
this information being used for? Will it ever be passed on to a wider
audience? A lot of good work is being done by non-professional birders but
it never gets the acknowledgement it deserves because many people appear
reluctant to publish. But that's another issue entirely.
David Geering
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