Larus armenicus(last update: |
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Coordinators: Amir Ben Dov (Israel) Mars Muusse (Netherlands) armenicus 1cy July armenicus 2cy Jan armenicus 3cy Jan armenicus sub-ad Jan armenicus adult Jan |
Larus armenicus 3cy, 18 August 2010, Maagan Michael, Israel. Picture: Amir Ben Dov. Bird in active complete moult. P6 fully grown, P7 halfway its final length, P8 missing, P9-P10 still old. Old outer primaries and upper row of lesser coverts very worn and bleached. New feathers in wing coverts, mantle and scapulars adult-like grey. This individual follows the common moult sequence in large gulls, with the median covert row now replaced (pale silvery grey) and the central and outer greater coverts missing, exposing the secondaries underneath. Primary moult has arrived at P6, with P7 halfway, and by this time, new secondaries should be visible next to P1. S1 is growing in this bird. It is also time to drop the central tail-feathers (R1), but this is hard to determine from these images. S1 is growing at this moment; all other secondaries are still old. The secondaries will be replaced inwards, in a first wave towards the body. When new secondaries grow in (from S1 first, next to P1), a the innermost secondaries will be dropped in a second wave, now from the body moulting outwards. The two waves will meet at about S16-S18, which will be the last new secondaries growing in to close the gap. The rectrices (tail-feathers) will be replaced centrifugal, hence first the central tail-feather pair (R1) and in a wave outwards. In this bird, the central tail-feathers may well be missing.
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