The Sun Rising over Farlington Marshes |
Today began
with a pre-dawn start at the Marsh. The aim was to try and catch some
meadow pipits out in the point field, and so we had to arrive early to get the
nets up. The method for catching meadow pipits involves putting three nets in a
triangle, around an isolated shrub. A recording of their song in the middle
attracts the birds into the trapping area. We only put up four nets, two in two
small areas of scrub and two in a right angle around a small bush. We didn't quite follow the normal method, but were convinced it would work.
Our Pipits Nets Set in a Right Angle |
Our first net
round produced a handful of blackcaps and a couple of robins. The next round
added a few more blackcaps and our first meadow pipits; after that it was
mainly meadow pipits. We ended the session on 88 birds, 54 of which were meadow
pipits; blackcap was the next most numerous species. The other species included
chiffchaff, greenfinch, dunnock, robin, sedge warbler and right at the end of
the session a handful of starling.
Ageing meadow
pipits is not something that I have covered before so having had the chance to
study so many birds it seems like the ideal time to do it. Adult meadow pipits undergo
a complete moult after breeding, whereas juvenile birds only do a partial
moult. This means that in the autumn there should be evidence of juvenile
feathers in the wing.
Meadow Pipit Anthus pratensis - note the long hind claw in this image. The most likely confusion species in the British Isles, Tree Pipit A. trivialis has a much shorter hind claw. |
According to Svensson some birds moult a number of their medium
and greater coverts and tertials, therefore birds should be identifiable by the
contrast between the new (adult) and old (juvenile) feathers. Adult birds on
the other hand will have wing feathers, all of the same generation and
therefore no contrast will be present. The following series of photos
illustrate this.
The image above illustrates an example of a first year birds wing. The greater coverts are pale fringed with the exception of the second covert from the left. This feather is an adult type feather and is strongly coloured buff.
In the image above it is possible to see the pronounced 'tooth' of the first year type medium coverts. The majority of the greater coverts are adult type feathers, with the exception of the innermost covert.
Above is another example of a first year birds wing. It is possible to see the contrast between the juvenile and adult coverts in the medium and greater coverts. In addition the two uppermost tertials have been replaced, but the lower one is still juvenile.
The majority of the tail in the image above is adult, but it is possible to see one remaining juvenile tail feather (the lower of the two central tail feathers). This image illustrates the difference in colour and shape with adult feather broader, more rounded at the tip and strongly coloured buff. The amount of wear on the tail feathers, their shape and the extent of white in the outer tail feathers was a very useful feature.
The most notable thing with handling so many birds was the difference in colouration between individuals. Some first year birds had very pale, almost white fringing, whereas others has fringing coloured similar to adult birds. It is important not to pay too much attention to the colour of fringing when ageing birds but look for evidence of a moult limit in the wings and tail and signs of abrasion.
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