11 Jan 2012

Bahrain - Aging A .s. coutelli Water Pipit at Alba Marsh

Aging Water Pipit in the late autumn / winter is difficult with Lars Svensson’s Identification of European Passerines saying that both adults and young have a partial moult in winter. Brendan has a way of aging coutelli Water Pipit in winter by checking the central pair of tail feathers and if they are pointed and worn then it is a bird born the previous summer (last breeding season). If the feathers are rounded and fresh then it is a bird born prior to the previous breeding season.
Water Pipit (A. s. coutelli) - Tail of second calendar year

Water Pipit (A. s. coutelli) - Partial moult of second calendar year

We have been catching a few birds at Alba Marsh in the last weeks even though they are difficult to catch as they seem to sense the nets and fly over them even with long four panel nets erected. The difference in wing length is quite marked with coutelli having a wing length of 79 – 92 average 86 and spinoletta have a wing length of 82 – 96 average 88.5. The majority of the birds caught in 2012 so far have had a wing length of <82 making them all fit on wing length alone the coutelli race. Plumage features also fit coutelli see previous post on this subject here
Water Pipit (A. s. coutelli) - second calendar year

Water Pipit (A. s. coutelli) - second calendar year

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