Monday, October 19, 2009

18th October,2009.

This weekend was when the survey of Light-bellied Brent Geese ( Branta bernicla hrota ) occurs, with a firther survey in mid-January, 2010. Very large numbers of these birds winter in Ireland and, usually, by comparison, we have very few to add in to the total. This population hails from Svalbard ( Spitsbergen ) and Greenland contrasted against the Dark-bellied form ( Branta bernicla ) whose breeding grounds are in Russia/ Western Siberia.

In September we see birds passing through on sea watches, with some staying over for a short while, very often at Loch Gruinart. Similar movements back north occur in May, making it one of the earliest and latest of the geese to be noted on passage. Our wintering population has grown very steadily in recent years from around 20 to < 40 with the birds usually centred on Loch Indaal. Figures this weekend suggest our wintering population has arrived and is of the same "order" as in recent winters.

By contrast a couple of weeks ago there was 28,000 at Strangford Loch and it will be interesting to see what figures arise from yesterday. A point of real interest is that the above flock had been looked at for juveniles and provided a return of <1%, which is a real worry. There has been several years where the birds had obviously enjoyed good breeding seasons, but this most recent one appears to have been rather different! Given the Barnacle Goose population wintering on the Solway Firth at Caerlaverock originates from Svalbard it will be interesting to compare the figures that come forward once the flocks there are scrutinized.

Our worry on Islay is what the situation might be with Greenland White-fronted Geese whose population has reduced in numbers in recent years and which could do with a really good boost to its numbers!!! Ageing observations on flocks will again produce commentary on this at some point in the winter!

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