Striated Pardalotes - juveniles

A juvenile Striated Pardalote - nominate Pardalotus striatus striatus

When we caught two young Striated Pardalotes Pardalotus striatus on the last trip to Charcoal Tank (see previous posts), I noticed that they were of different subspecies. The one above is of the nominate type striatus, which only breeds in Tasmania and spends autumn and winter on mainland Australia, where it overlaps the range of two subspecies, ornatus and substriatus. The nominate has yellow wing-spots, colouring on the tips of the greater primary coverts, while the subspecies have red wing-spots - see below.

The yellow wing-spot on the primary coverts of a  Pardalotus striatus striatus

The red wing-spot  on the primary coverts of a Pardalotus striatus substriatus
(The wide band of white on primaries differentiates this subspecies from the similar subspecies ornatus, which has narrow white edges to the primaries. See post of  17th September 2012)

A juvenile Pardalotus striatus substriatus

Then I noticed that the striatus juvenile's moult into adult type plumage was less advanced than that of the substriatus bird. In particular, its crown was still spotted rather than streaked like that of the substriatus (see below). This is only a sample of one from each subspecies, but I wonder whether the young Tasmanian striatus birds deliberately delay their moult until they have migrated across the Bass strait and settled in their winter range on the mainland. Meanwhile the resident subspecies of South-west New South wales, substriatus, begin their moult as soon as possible. Both birds were caught on the 15th March 2014. If the Tasmanian birds migrate from March-April (HANZAB), this bird would have been one of the earlier to leave. Would it have been one of the earlier to hatch too? If so the delay in its moult would be more likely a strategy to moult post migration. I would be grateful if anyone has more information on the plumages or migration strategy of juvenile Tasmanian Pardalotus striatus striatus.

Juvenile Pardalotus striatus striatus,
with a spotted crown

Juvenile Pardalotus striatus substriatus,
with a partially streaked crown

                               

Gang Gang Cockatoos

A pair of Gang Gangs inspect a potential nest hole

There seemed to be parrots everywhere in the bush yesterday as they were all prospecting, exploring, or defending nest holes. This  hole looks a bit too large for these Gang Gang Cockatoos, although there might have been a tighter cavity down at the bottom, so the male went in for a look-see. These parrots are such quiet and approachable birds and the male's bright red helmet is very smart.

The male seems to have dipped his head into a pot of red paint lying in the hole

The twist of red feathers from the back of his head over the crown is a small but
spectacular piece of plumage. She also has a crest, but it lies tucked away. The female's plumage is just as well evolved as the males, although more for the purpose of concealing her. She has a fine pattern of bush-colouring, which hides her well as they sit quietly in the trees. These birds are easily overlooked, unless one is familiar with their subdued creaky calls, or their habit of dropping crunched-open gum nuts to the ground below.

The female has kept her head clean