First year plumage
I was out west over last weekend catching birds as part the long-term study at The Charcoal Tank Nature Reserve, which is a cooperative site and the trip was organised by Mark Clayton. The most noticeable trend that I noticed amongst the birds we caught and banded was the high proportion of young birds. It is the end of the breeding season for the passerines and most of the young were free-flying and independent, although some were still being fed by attending parents. The other point I noticed was the different strategies of moult that the various species have adapted to suit their lifestyles. Below are only a few examples.
|
A first year Sacred Kingfisher Todiramphus sanctus |
This young Scared Kingfisher was in perfect condition with a full set of fully-grown flight feathers, all with fine clean edges. This is a single brooded migrant species and the adults had probably flown north already. The buff tips to this bird's crown and covert feathers indicate that it is a bird hatched in the recent breeding season. So, this bird was ready to fly north probably following innate properties to guide it to its winter quarters in the north of Australia or perhaps Papua New guinea.
|
A first year Yellow-plumed Honeyeater Lichenostomus ornatus |
This young Yellow-plumed Honeyeater is clearly very young, as it still has a yellow gape - the flap of skin at the base of its bill. Therefore, this bird was from a late brood, perhaps a second or even a third reared by its parents. Unlike the kingfisher, this is less critical as it will not have to fly far very soon. At most it will probably range locally or nomadically in and around the breeding region. This bird will join a flock of its species, probably a mixed flock of several honeyeater species, unlike the kingfisher which will live singly until it returns to breed.
|
The same Yellow-plumed Honeyeater - face on |
The plumage details which discern this bird as a youngster are: the brown feathers on its back and crown, the incompletely-grown wing coverts, some of which are still in quill, the yellow base to its bill, the pale brown streaks on its throat and breast and the thin yellow line across the side of its neck.
|
An adult Yellow-plumed Honeyeater - face on |
The plumage details which discern this as an adult Yellow-plumed Honeyeater are: the bright yellow crown with no brown feathers, the yellow plume feathers standing out from the sides of its neck, the heavy black streaks on its throat and breast, and the lustrous black bill.
|
A first-year Restless Flycatcher Myiagra inquieta |
The young birds of the two previous species were both similar in plumage pattern to the adults, only less brightly marked. However, this young Restless Flycatcher is different from the adult birds, it has an orange/buff breast, the adults have almost pure white breasts. These flycatchers live singly when not breeding, or at most in pairs if they stay in their local area, but very little is definitely known of their non-breeding movements. They are also multi-brooded, so any young birds from early broods have to share habitat with breeding pairs, and those pairs would not be their parents if they move from their natal area. Therefore, by having a distinctly coloured breast any adult birds can identify them as youngsters and not regard them as a threat to their breeding, So they are less likely to attack the young birds and the immature birds can live unobtrusively with less harassment. This young bird has a fully grown set of fight feathers, but the primaries and their coverts are a dull dark grey, these are shiny black in the adults. Although, shiny black is not a true appraisal of this wonderfully coloured bird's plumage. The dark feathers have a rich metallic blue lustre, and when they raise their crest as in the image below, they present a very vivid frontage. This young bird has not quite grown all the lustrous feathers on its crown, some still have dull tips. But by next year's breeding season, they will be truly magnificent and offset by a bright white breast. A handsome bird indeed.
|
The same Restless Flycatcher - face on |
Thanks for the good information about juvenile plumage. Great pics too.
ReplyDeleteThanks Stuart for the really useful information. The photos are stunning!
ReplyDeleteThanks for the feedback, that is always helpful in guiding me what to post. I might add features of other species in a follow up page.
ReplyDelete