Monday, 10 September 2012

16,000 Brent at Strangford!

The unprecedented influx of Brent to Strangford (~ 5000 birds by 28-30 August) has now risen to approximately 16000 individuals, counted as part of the long-term annual monitoring by Kerry Mackie at WWT Castle Espie.
Folk have been busy resighting ringed birds from these flocks as well as smaller early groups along the west Scottish coastline (including < 1000 on Islay).
We've never seen this many individuals this early in the season and we wonder what it may mean for how the breeding season went. One possible explanation is that the also unprecedented melt of the polar ice this year (minimum recorded extent - see bbc and canadian ice monitoring websites for info) is a sign that conditions were favourable for breeding, the birds have bred and had the opportunity to leave early. A second, conflicting hypothesis might be that the season was dreadful. A good (sunny) late summer season doesn't necessarily mean the season started off well. And those of us who've seen the breeding range in the summer have seen that there are large regional differences with the archipelago of the Queen Elizabeth Islands. We aqctually know very little about how all of this works.

What is sure is that irrespective we wouldn't see large numbers of young yet. These will generally be the last to leave the breeding grounds (as adults await continued development of their young for the flight to Greenland/Iceland) and their schedule will mean that the young will form a disproportionately high % of flocks in Iceland this month. In Ireland we'd expect to see a predominance of failed- or non-breeders at this early part of the season. The jury is out and whilst I have a prediction I'm not prepared to stick my neck out just yet...

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