Tuesday, 30 October 2012

Seabird Summary 2012

Fulmars (pictured left) – have not had a good year. We counted 133 nests, which is a decrease of 35% on last year’s count, well below the 10-year mean of 172 and about half of the 28-year mean. Although we weren’t able to carry out a formal study of fulmar breeding success, we only found 5 fulmar chicks that had reached fledging stage on the whole reserve.

Shags – well here, things looked a bit more rosy with 171 nests counted, an increase of 7% on 2011, and similar to the counts since 2005. However, this is below the 10-year mean of 192 AON, and well below the 28-year mean of 250 AON. Breeding success was down on last year (but last year was an exceptionally good year) but about the same as the 10-year and the 23-year means. Shags this year fledged, on average, 1.25 young per active nest.

Herring Gulls – have done OK this year as well, 266 nests counted which is above the 10-year mean, but below the 28-year mean of 354 AON.

Kittiwake – continue to have a difficult time of it. This year’s count of 4,314 nests is the lowest on record, well below the 10-year mean of 5,653 AON, and less than half the 28-year mean of 10,631 AON. However, to put it in perspective, although the number of kittiwakes has declined by 78% since the highest count in 1989, the counts since 2009 are now in the region of the counts from the 1950s. As far as breeding success goes, not as good as last year (but like the shags, last year was exceptionally good), with only 0.48 young fledged per nest. However, this is about the same as the 10-year mean, and only slightly below the 26-year mean.

Guillemot & Razorbills (latter pictured right) – we do not have the resources to count all the guillemots and razorbills every year, but we do count numbers on the same study plots every year so that we can compare whether numbers. This year guillemot numbers have decreased since last year, and are below both the 10-year and the 28-year means. Razorbill numbers are down on last year too, but are about the same as the 10-year mean, if below the 28-year mean.

Puffins – sadly for many, the puffin breeding numbers went down again this year from 7 birds ashore during the height of the breeding season (so probably with chicks in burrows) last year, to just 4 this year.

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