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Gray-cheeked Thrush (Catharus minimus) |
Seasonal
status at MBO:
| JAN
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FEB
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MAR
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APR
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MAY
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JUN
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JUL
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AUG
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SEP
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OCT
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NOV
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DEC
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QUICK TIPS:
| 1) Look
at the greater coverts - the presence of buffy-white
shaft streaks indicates a HY/SY bird, however the
absence of buffy-white shaft streaks is NOT an
entirely reliable indicator of AHY/ASY, as some HY/SY
birds may lack these markings
2) Examine
the outermost primary (p10) - on HY/SY birds it
is rounded and 3-7 mm shorter than the primary
coverts, while on AHY/ASY birds it is narrow,
pointed, and 5-12 mm shorter than the primary coverts
3) Look
at the shape of the rectrices - they are
tapered and relatively abraded on HY/SY birds, but
rounded and relatively fresh on AHY/ASY birds |
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Ageing and sexing overview:
Ageing and sexing details:
|
after-second-year
unknown |
The face of Grey-cheeked Thrushes should be
looked at closely to verify species, but overall the body plumage
provides little information about age or sex.
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2006
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2006
Note that p10 is considerably shorter than the adjacent primary coverts,
and is narrow and pointed; there are no pale markings on any of the
greater coverts.
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2006
While thrushes of any age may have a slight point at the tip of their
rectrices, note that the feathers are generally broad and rounded at the
tip, rather than tapered also they usually appear relatively fresh.
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2006
RETURN TO AGE/SEX
OVERVIEW
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2005
The pale marks along the shaft of the greater coverts indicate that
these are retained juvenal feathers, identifying the bird as
second-year.
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2005
Compared to after-second-year birds, the rectrices on second-year birds
are narrower, with a more tapered pointed end, and often show a greater
amount of wear.
Photo by Marcel Gahbauer,
McGill Bird Observatory, May 2005
RETURN TO AGE/SEX
OVERVIEW
Photo by Marcel Gahbauer,
McGill Bird Observatory, September 2005
The absence of pale shaft streaks on the outer
greater coverts is suggestive of an after-hatch-year bird, but for
confirmation the narrow and pointed outer primary (p10) should be
checked (not visible in this photo).
Photo by Marcel Gahbauer,
McGill Bird Observatory, September 2005
The rectrices in the
photo below show the broad and rounded shape typical of after-hatch-year
birds.
Photo by Marcel Gahbauer,
McGill Bird Observatory, September 2005
RETURN TO AGE/SEX
OVERVIEW
In general the body plumage of thrushes is
not helpful for ageing or sexing, but occasionally as in the examples
below, the pale tips on the greater coverts are visible even on a
perched bird, allowing it to be easily identified as a hatch-year.
Photo by Marie-Anne Hudson,
McGill Bird Observatory, September 2007
Photo by Marcel Gahbauer,
McGill Bird Observatory, September 2005
The pale tips of the greater coverts are indicative
of a hatch-year bird, but the shape and length of the outer primary, p10
(not visible in these photos) should be checked to confirm age.
Photo by Marie-Anne Hudson, McGill Bird Observatory, September 2007
Photo by Marcel Gahbauer,
McGill Bird Observatory, September 2005
The relatively narrow and
pointed rectrices in the photos below show the typical shape for
hatch-year thrushes.
Photo by Marie-Anne Hudson, McGill Bird Observatory, September 2007
Photo by Marcel Gahbauer,
McGill Bird Observatory, September 2005
RETURN TO AGE/SEX
OVERVIEW
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