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General
description:
By mid-winter, many 2cy michahellis
continue the post-juvenile moult in the wing-coverts and the tertials.
Year 2002, we checked limited numbers of 2cy michahellis as Etaples
in NW France holds only a few 10's of birds. More information on the
Etaples-site can be found on the Le
Portel Page).
A very few January 2cy birds show third generation
scapulars, which are grey-based with an ill-defined brown or black
pattern. The head normally appears smudgy, with a dark patch around the
eye, extending to the nape. The hind-neck has a contrasting neck-collar,
running down along the side-breast towards the flanks and belly. An
example can be found in the first image, showing a strong male michahellis
with the head rather pale.
Remiges &
rectrices moult stage and
pace:
By January, replacement of the primaries and rectrices hasn't
started in 2cy michahellis. The first primaries are only dropped by mid-April.
About 5% of michahellis includes tail-feathers in the partial moult
in autumn and may show second generation rectrices by January. At this
moment, it's not completely clear whether this moult in the rectrices
continues throughout the wintering months, as limited data are not
sufficient to support the hypothesis.
Wing-covert
moult stage and pace:
In several sections of 1cy michahellis
it's mentioned that birds include wing-coverts in the post-juvenile moult
(unlike argentatus / argenteus where this post-juvenile
moult is confined to the scapulars, and only seldom single
wing-coverts are included). The general conclusion is that
between September (in first calendar year) and January (in second calendar year)
the moult is not suspended but replacement progresses in a slow pace. Several pictures
in this section show birds which are still actively moulting the coverts,
with growing or missing coverts. The first
image shows growing greater coverts and the fourth
image shows a bird with missing coverts.
However, there are still 2cy birds which have all the wing-coverts and
tertials juvenile.
Mantle &
scapular moult stage and pace:
By January, the second
generation feathers in the lowest row of lower scapulars are finally
visible; these lowest scapulars are moulted last in line. The moult to third
generation scapulars may start in some birds, although most of these
birds will only replace a single or a few lower upper scapulars in January
at Le Portel, NW France.
Nonetheless, missing lower upper scapulars is not uncommon in January in
2cy birds. The fresh third generation scapulars show anchor an bar
patterns not unlike the second generation feathers, although these third
generation feathers are often grey-based. Later in the season,
from April onwards the third generation feathers may look more adult-like,
with the bases extensive grey and the pattern reduced to an ill-defined dark
shaft-streak or even completely plain grey (although these third
generation feathers often appear slightly browner towards the edges and
tip). The last lower scapulars, which can be found in the lowest row,
often the rear feathers on the back, are moulted to second generation.
Subsequently, in the scapulars simultaneous moult can be found to second
generation feathers (in the lower scapulars) and to third generation
feathers (in the upper scapulars).
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NLA 5362457: Michahellis 2cy, January 15 2007, Amsterdam, the Netherlands. Ringed at about the same location.
Photo 01: Michahellis 2cy, January 05 2002, Le Portel, NW France. Actively moulting the wing-coverts.
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