This report presents the results of seabird monitoring on Fair Isle in 2000, the 15th season of work. Some of the data collected in previous years have been
re-analysed and therefore some of the results for the years 1986-99 published in this report may differ slightly from those in previous years.
1.1 Whole island census 2000
Population changes from 1999 were as follows:
- Northern gannet: +3.5% to 1,162 apparently occupied nests (AON);
- Arctic skua: -5.8% to 65 apparently occupied territories (AOT);
- Great skua: +2.3% to 135 AOT;
- Mew gull: +33.3% to 8 nests;
- Common tern: 0.0% 3 pairs;
- Arctic tern: +122.6% to 1,251 apparently incubating adults (AIA).
Whole island counts were carried out for four species, in conjunction with 'Seabird 2000':
1.2 Population changes at monitored plots
- The whole island census of black-legged kittiwakes revealed 8,175 AON, a decrease of 29.8% since the last complete island count in 1997.
- The whole island census of northern fulmars revealed 20,424 apparently occupied sites (AOS), a decrease of 52.9% since the last complete island
count in 1996.
- The whole island census of razorbills revealed a total of 3,599 birds, an increase of 9.2% since the last complete island count in 1998.
- The whole island census of Atlantic puffins produced an estimate of 80,000 birds. This would have represented a 100% increase on the 1995
estimate of 40,000 birds, but the 2000 figure may be an over-estimate as the regular presence of great skuas at the Roskilie colony almost
certainly resulted in there being a low % of the population visible (see Results section 4.1.4).
Northern fulmars, European shags, and black and common guillemots all increased at monitored plots in 2000 compared with 1999, the first three species
bucking the trend of recent years. European shags showed a substantial increase of 61.4% at the five monitored beaches, while northern fulmars (contrary to
the results of the whole island census), black and common guillemots all increased by approximately 20%. Black-legged kittiwakes continued their steady
long-term decline; overall numbers at monitoring plots were 4.7% lower in 2000 compared with 1999, but four of the ten sites did show small
1.3 Breeding productivity
The 2000 breeding season was generally productive, but affected by a storm on 13 June, which resulted in heavy losses on the exposed west coast. This meant
that while plots on the sheltered east coast did well, those exposed to the storms did badly. As a result, northern gannet, razorbill and Atlantic puffin
all had a below average season (razorbills had their lowest productivity since monitoring began and northern gannet their lowest since 1991). Black-legged
kittiwake, European shag, northern fulmar, black guillemot and Arctic terns all had an above average breeding season. However, the apparent overall success
of European shags (highest productivity since monitoring began in 1986) may be misleading as the monitoring plot is on the east coast; European shags on the
west coast were the hardest hit of all species during the June storms.
1.4 Adult survival
Black-legged kittiwakes showed an increased survival compared with recent years. From a total of 33 birds known to be alive in 1999, 26 were seen in 2000,
an apparent over-winter survival from 1999-2000 of 78.8%. Ten new birds were ringed in 2000.
Atlantic puffins showed an uncharacteristically low survival; from a total of 104 birds known to be alive in 1999, just 75 were located in 2000, giving a
survival estimate from 1999-2000 of 72.1%, the lowest since recording began in 1986. Fifteen new birds were colour-ringed in 2000.
Sandeels comprised the majority of food items for European shags, black-legged kittiwakes, common guillemots, razorbills and Atlantic puffins in 2000. The
lengths of sandeels brought to common guillemot chicks, and load weights of Atlantic puffin feeds were about average.
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