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FOULA HERITAGE
Foula - The Edge of the World
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Foula 1924-37 Telegraph Installation Foula 1936 The Edge of the World Red-throated Diver or Rain Goose
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Seabird monitoring in Foula 2006 Sheila C. Gear EIDERSEiders had a late breeding season, with females still on eggs well into July. No females with chicks were observed on the west side of the island. Adult numbers were badly down on previous years. Chick numbers halved over the two counts, suggesting possible high predation. Throughout the winter, although scattered numbers were seen along the coast, the normal big raft of 200 – 500 birds was not observed. Table 1. Eider counts in Foula 2006
Both counts were done in good conditions. On 22nd July, the wind was variable light with sun. On 24th August, the wind was north east light and it was cloudy bright.
RED-THROATED DIVERSThe breeding season was late and there were only nine observed breeding attempts (or possibly ten; two adults being observed on Loch F throughout the season but no scrape found). All three pools at lochs L, M and N were occupied for the first time for several years. Seven pairs produced chicks, indicating that the first part of the breeding season was quite successful. However only three chicks survived to be large enough to possibly fledge successfully. The rest disappeared, mainly during the second half of July. At this stage, adults frequently no longer stay with their chicks throughout the day when feed is scarce, leaving them vulnerable to possible predation. Table 2. Red-throated divers in Foula in 2006
FULMARSAlthough breeding was later than usual, with many chicks still downy on 19th Aug, they went on to fledge successfully. No dead chicks were seen. Mean productivity of plots was 0.63. Five sites that were not classified as Apparently Occupied Sites (AOSs) also produced fledglings. AOSs were considered to be those occupied on each of the four observations at the end of May and beginning of June. Table 3. Counts and productivity of Fulmars in study plots in Foula in 2006
MANX SHEARWATERS A bird was heard calling on the night of 9th Sept.STORM PETRELS AND LEACH’S PETRELS Petrels were not much in evidence this year. A survey of accessible areas frequented by petrels was carried out using tape-playback, from 26th June to 26th July. No AOSs were found. However many large areas suitable for breeding are not accessible. Only one burrow in the small Leaches colony near the top of the Noup had visible signs of possible occupation but no response was heard.
SHAGS
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Plots |
Attended sites |
Well-built nests |
Chicks fledged |
Productivity per nest |
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Headlicliv |
4 |
4 |
3-5 |
0.75-1.25 |
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Rubbish tip |
9 |
8 |
6-8 |
0.75-1.00 |
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Gloor |
5 |
5 |
2 |
0.40 |
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Little Sur Peidel |
2 |
1 |
0 |
0 |
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Sur Peidel |
6 |
5 |
7-8 |
1.40-1.60 |
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Sutherakeeden |
4 |
2 |
2 |
1.00 |
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Head o da Hurd |
0 |
0 |
0 |
0 |
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Skarvatung |
8 |
8 |
6-9 |
0.75-1.12 |
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TOTAL |
38 |
33 |
26-34 |
0.63-1.03 |
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2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
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<1.01 |
<0.65 |
<0.30 |
<0.00 |
0.00 |
0.83 |
ARCTIC SKUAS
Arctic Skuas had another very bad breeding season. Although better than 2005, conditions were still not good enough for the production of fledglings.
Birds were slow to return. The first was seen on 26th April but numbers seen during the first three weeks of May were very low, nine and 12 being the maximum. On 24th May, after a fine, warm day, there was an influx of birds and by evening about half the normal number of breeding birds were back on territory.
In poor breeding seasons, such as this, the number of Apparently Occupied territories (AOTs) is difficult to ascertain with complete accuracy as territories may be very poorly attended, with some birds only being seen once. Seventy-four pairs were seen on territory and a further five colour ringed birds were seen once on territory with no apparent permanent partner, giving a possible 79 AOTs. Three other apparent pairs were seen moving around various different territories.
Only four pairs were seen to lay in May, with the first egg observed 26th May. Mean clutch size observed was 1.68. A total of 61 pairs was seen to lay. There were two relays.
Twenty-five pairs hatched out chicks. Mean hatching date was c.1st July (normal expected hatching date c.20th June). Most chicks did not appear to be fed by the parent birds and died or disappeared during the first few days after hatching. Fourteen chicks survived long enough to be ringed. Regurgitates were of larval whitefish. Two chicks survived to fledge on 25th July and 10th August. Productivity per possible AOT was 0.03.
Table 6. Productivity of Arctic Skuas in Foula 2001-2006
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2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
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<0.09 (<10) |
<0.08 (<10) |
0.00 (0) |
0.00 |
0.01 (1) |
0.03 (2.) |
No immature non-breeding birds were seen.
Ninety-two identifiable colour ringed birds were seen and a further nine birds that were difficult to identify with certainty because of missing rings were also seen, giving a total of 101. Several had been missing for a number of years. Twenty two birds seen last year were missing, giving a possible mortality rate of 27%, although it is likely to be lower than this due to lost colour rings and to some birds missing a year because of the continuing poor conditions for breeding.
Table
7. When colour ringed Arctic Skuas, identified in 2006, were last
seen in Foula
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Birds seen 2005 |
68 |
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Birds not seen since 2004 |
16 |
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Birds not seen since 2003 |
5 |
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Birds not seen since 2002 |
0 |
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Birds not seen since 2001 |
1 |
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Birds not seen since 2000 |
0 |
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Birds not seen since 1999 |
2 |
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Total birds seen |
92 |
GREAT SKUAS
Bonxies had a rather poor, late season. The first sighting was two on 2nd April. On 12th May, there were a few scrapes but none had laid. The first egg was seen on 15th May. Some territories were poorly defended or not defended at all. Many chicks disappeared through the season and cannibalism was high during the last half of August.
Table 8. Productivity of Bonxies in Foula 2004-2006
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No AOTs in study plot 2004 |
Productivity (young/AOT) 2004 |
No AOTs in study plot 2005 |
Productivity (young/AOT) 2005 |
No AOTs in study plot 2006 |
Productivity (young/AOT) 2006 |
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145 |
0.014 |
22 |
0.32 |
20 |
0.45 |
COMMON GULLS
Three pairs laid at the small new colony at the Groups quarry. Ravens were observed twice taking all the eggs. Two chicks fledged successfully from the third re-lays, on 15th August.
LESSER BLACK-BACKED GULLS
One pair nested at the Swaa, alongside Herring Gulls.
Numbers showed an increase of 18.60% from 2005 and were comparable to 2003. Resting and bathing birds were evident in numbers, in places where they have been few or absent for a number of years, including 316 at the Freshwater Geo on 3rd August.
Two counts were done of well built nests. Swell prevented an accurate count of some sites on 7th June, particularly the section of the colony with the most nests, from Mirkie to Waster Hoevda, so a second count was done on 3rd July, which although late, was deemed to be more accurate.
Table 9. Counts of Kittiwakes in Foula in 2006
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Site |
Date |
Date |
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07.06.06 |
03.07.06 |
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South of Gloor |
24 |
26 |
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Granni Geo |
7 |
8 |
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Skirnawilse |
47 |
34 |
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Stee |
92 |
96 |
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Waster Hoevda |