Wednesday, 20 May 2009

How many Icelands?

1. Iceland Gull from 30th January 2008. A cream toned bird with a mainly dark bill. Typical Iceland structure.

2. The latest bird, photo taken on 13th May. A full breasted bird, overall white in tone, limited 'ghost' tail band and complete primaries on left and right wing (have to believe me about the left wing).

3. Same bird as above (plate 2), 13th May.

4. 1st summer Iceland Gull from 18th April. Some grey feathering on the mantle.

5. 1st summer Iceland Gull, 18th April, showing missing primary on left wing and also a fairly obvious tail band.

As of yesterday there was still an Iceland Gull present on the farm- the first May record and still hanging around. Been trying to work out how many different Iceland Gulls I saw on the farm this winter. I am puzzled as to whether a cream bird in December can fade to a white bird in April. I think the April and May bird are different (April bird had a missing primary on left wing, grey mantle feathering and a noticeable tail band)- structurally they appeared different too.


Gavin Haig said...

We had a creamy/off-white bird in Feb fade to pretty much white in late April. We had the same challenge as you re. identifying individuals. The most reliable method was to photograph them and compare the darker feather markings. This proved conclusive, with diagnostic markings still visible as the plumage faded (until the marks disappeared completely of course!). We had a definite 5 different individuals. Don't know if you can photograph yours close enough to see feather markings? If not, then this wasn't much help was it? :o)

Peter Alfrey said...

Interesting to confirm that. Some birds appear to start of white so difficult to tell which ones are fading and which ones are pale birds.
Definately of help- will keep this in mind for next year- and start logging some diagnostic markings on birds at the start of the season.
Cheers Gavin