20 September 2005news.scotsman.com
Further evidence of a decline in the seabird population has been found on Scotland's most remote nature reserve.
An ornithological survey by Scottish Natural Heritage (SNH) has revealed that seabirds in North Rona have suffered a poor breeding season, similar to that in many other island colonies in the north-east Atlantic
With the rock Sula Sgeir, North Rona, 45 miles north from the Butt of Lewis and from Cape Wrath, has been a National Nature Reserve since 1956. Staff who spent five days there found that some bird populations had almost halved while others were down by a third.
John Love, an SNH area officer based in South Uist who was part of the group, said: "Immediately on arrival, we were conscious of fewer seabirds around the cliffs and even less clamour. The counts undertaken over the next four days and recently analysed bore this out.
"The poor breeding season is a trend that seems to have been repeated elsewhere in the north-west of Scotland this year. Whatever the reason, it underlines the importance of regularly monitoring remote islands and their seabirds, in order to detect changes in the state of man's own environment."
Usually, about 1,000 pairs of great black-backed gulls nest all over Rona, but the ornithologists counted only 550 pairs. Kittiwakes, normally 3,500 pairs, this year barely exceeded 1,800 pairs.
The auks, guillemots and razorbills were down by a third and numbers of hole-nesting puffins also seemed to be down. The biggest decline, however, was among shags, with the party able to locate only 21 nests where in previous years 150 or more would have been found.
The men of Ness in Lewis have just returned from their annual guga harvest in Sula Sgeir, with a licence to take 2,000 young gannets for human consumption, a local delicacy in Lewis.
Earlier this month, experts on reserves run by the Royal Society for the Protection of Birds (RSPB), the National Trust for Scotland (NTS) and the Scottish Wildlife Trust said that the decline among seabirds had spread to western reserves such as those on Tiree, St Kilda and Canna.
On St Kilda, which is owned and run by the NTS, there was a spectacular breeding failure for puffins, with only 26 per cent of burrows producing chicks, compared with a normal figure of 71 per cent.
The kittiwake colony on Canna was another notable casualty, with barely five chicks fledged out of 1,000 pairs.
Guillemots, razorbills and Arctic tern were also hit, with the most recent survey on Tiree showing only four guillemot chicks at Ceann a' Mhara, from a total of 2,173 birds. In a normal year, there would be about 1,500 chicks in this colony.
Seabirds in Shetland have also been suffering and this was at first put down to overfishing for sand eels, the main prey of many gulls and auks.
Scientists are now considering the effects of global warming, with warmer seas forcing fish shoals further north, out of range of foraging seabirds.
Experts say that while it is normal for seabirds to suffer periodic failures, the frequency seems to have been increasing in recent years.
Scotland has about 45 per cent of all the seabirds in the European Union nesting on its coasts, making it a significant tourist attraction.
However, scientists say that the recent breeding failures pose a significant threat to the future of the important populations.
They say that the lack of some seabird species will not mean that others will come in to take their place.
An SNH spokesman said: "The birds that can thrive in the harsh conditions in these remote places are already there.
"Other species would find it too hard to acclimatise to these conditions."
