Realistically our first reliable assessment of how good or bad this (2012) breeding season will have been will be when Gudmundur, Magnus and others in Iceland get access to some of the large flocks in western Iceland which will happen in the coming days.
Kathy Dickson a senior waterbird biologist at the Canadian Wildlife Service has reported that although she has no direct information on the performance of species breeding in the high arctic (~75 degrees N +), terrible weather in the low arctic (Baffin Island latitiude) lead to a poor breeding year for many species. The team working on Atlantic Brant (which look like ours, winter on the eastern seaboard of the US and breeding on Baffin and surrounding islands) had difficulty finding enough families to ring and many of the adults (failed/non-breeders) were already moulted and mobile. I agree with Kathy that this abundance of flying adults are probably adults that we would classify as 'failed' breeders who, because they have no reason not to, moult early.
Early moulters are mobile more quickly and one would have thought would thus migrate earlier. It wouldn't be a huge leap in imagination to think that this may have happened for 'our' Brent also.
Thanks to Kathy for this insight from the low arctic Brant in Baffin!
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...
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...
Friday, 31 August 2012
The Brent are back!!
Reports are filtering down to Cornwall from various parts of the Emerald Isle, and further north in Iceland, that the brent are returning from their summer jaunt to the far north. Already there are an impressive 5000 or so gathering at the north end of Strangford Lough, and there has been a trickle of birds been seen flying south past the Bridges of Ross (in County Clare over on the West Coast) in recent days too - why any of the seawatchers here are counting geese rather than keeping an eye out for more exotic things is anyone's guess!!
All this means its hopefully not too long until I'm escape the computer again and am back enjoying views like this!! Hopefully the relatively early return of such high numbers of geese implies there are lots of non-breeding immatures from last years successful breeding season rather than that it has been a bad breeding season as was the case for so many subarctic species. We'll only get a true idea of this when family parties begin to return in a week or two...
All this means its hopefully not too long until I'm escape the computer again and am back enjoying views like this!! Hopefully the relatively early return of such high numbers of geese implies there are lots of non-breeding immatures from last years successful breeding season rather than that it has been a bad breeding season as was the case for so many subarctic species. We'll only get a true idea of this when family parties begin to return in a week or two...
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