In May we were catching and colour-ringing Whimbrel as they
headed north as part of a larger project set up by Tony Cross (see
ruffledfeathers)
with the aim of trying to find out more
about the migration of this transient species. So far we have only had one
report of the 34 we ringed in Pembs in spring, a bird which unfortunately died after colliding
with electric cables before managing to leave Pembs. Whimbrel have recently been passing through on
their way back from their breeding grounds further north and during four routine
ringing sessions at the Gann Estuary near Dale since early August 4 individuals
have been caught. This total is surprisingly low given that 1498 were counted
passing Strumble Head on 18
th August (see
Strumble blog).
Although the sample size is small it was noticed that the
autumn birds were heavier than those in spring (average of 486g compared to
410g), presumably implying that although they pass through in good numbers in
autumn, they don’t need to feed up, so many must carry straight on without
stopping. Anyway, if anyone is out watching Whimbrel then it is worth looking
for a numbered yellow colour-ring above the knee on the right leg and a green one
below, as in the photo below.
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| Adult Whimbrel with colour-rings |
6 Curlews have also been ringed and weighed this autumn and their
weights were quite a bit lower than that expected for this time of year with an average of 646g compared to the
national average of 770g in autumn (BTO website), but the sample size is still too small to draw any
confident conclusions.
The Whimbrel study has had a very interesting ‘bycatch’ with
the most recent session producing 40 waders of 10 species. Half of these were
Oystercatchers which generated much discussion on how to age them correctly - in the end we think we sussed it! (see photos
below). Also ringed were; 4 Curlew, 4 Dunlin, 5 Bar-tailed Godwit, 2 Redshank,
and singles of Greenshank, Black-tailed Godwit, Common Sandpiper and Ruff.
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| Oystercatcher age code 3 - born this year |
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| Oystercatcher age code 5 - born last year |
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| Oystercatcher age code 7 - born two years ago |
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| Oystercatcher age code 8 - at least 3 years old |
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| Male and female juvenile Bar-tailed Godwits - the female has the longer bill |
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| Juvenile Black-tailed Godwit |
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| Greenshank |
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| male Ruff |
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Juv Common Sandpiper
|
Paddy J and Paul W
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