How long do you examine each bird
before releasing it? It usually takes less than one minute
to process each bird.
How do you determine a bird’s age? Whether it
is male or female? In general, adult males are stunningly
colorful with blue heads, red underparts and green backs
while females and immatures (of both sexes) are bright
yellow-green overall (commonly referred to as “green
birds”). Males and females in their first year of life look
identical and, except during the breeding season, cannot be
separated. During the breeding season these “green birds”
have certain features that allow us to determine their sex.
Females develop a brood patch which is a highly vascular,
featherless area on their breast which allows heat to be
transferred to the eggs during incubation.
Determining the age of a painted bunting can
be a difficult process that is compounded by the fact the
males do not get their colorful plumage until after their
first breeding season. It requires examining certain tracts
of feathers on the wing and knowing their molt strategy.
Subtle differences in the color of the feathers on a bird’s
wing can give insight into its age. For example, adult
female painted buntings (birds at least two years old) in the
summer will have a very uniform looking wing with bright
green edging on their greater coverts and primary coverts.
Second-year birds (birds that were born the previous
summer) will show a difference between the greater coverts
and the primary. The greater coverts will have bright green
edging while the primary coverts will be entirely dull
brown. In late summer and fall, juvenile painted buntings
of both sexes can be aged by the presence of buffy tips on
the greater coverts.
What are you checking here? Brood patch:
Indication that this bird is a female. Age: The presence
of green edging on the greater coverts (the inner group of
the feathers) and the dull brown primary coverts (the outer
group that the pencil is pointing at) indicates that this is a
second-year bird that was born the previous summer.
How old is this bird? Adult: note the bright green
edging on the primary coverts. n
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