14. December 2009

67 Rhunahaorine, Kintyre, Strathclyde Region

History: Berry (1939) reported White-fronted Geese from Kintyre, but the implication from an article in The Field from 1923 was that “of the large number of geese migrating through Kintyre, the bulk was certainly Whitefronted”.  Although the Machrihanish flock was known to earlier ornithologists, the flock frequenting the Rhunahaorine area seems likely to have been of more recent origin.  One local farmer questioned locally could not recall geese being present in the area in the 1930s, with the first (a flock of 18 he could remember) arriving during the winter of 1934/5.  In 1935/6 a similar number wintered and numbers rose in subsequent years (C. Currie pers. comm.).  As R&O (1979) have commented, the existing counts seem to show a gradual increase in numbers, and the figure shown below may represent the only flock of Greenland White-fronted Geese for which we have a complete numerical history!  Nevertheless, we would caution too great a belief in the accuracy of the counts, as this area is notoriously difficult to count.  In one classic example in November 1982, two experienced counters obtained counts of 560 and 650 under normal circumstances on the same day.  Following helicopter disturbance, 865 were counted flying back to the feeding areas, i.e. 200 more than had been counted the same morning!

Status: International importance (R&O 54).  Whatever the inaccuracy in individual counts, the numbers do strongly suggest a long extended period of slow expansion in numbers from just 18 at initial “colonisation” in 1934 to peak at 1594 individuals in 2001.  Numbers have fallen back slightly since that time.

Maximum winter counts:

Breeding success: Assessment of breeding success has been regular and constant, being carried out by Malcolm Ogilvie over a great many years.  The pattern in annual production has followed that on Islay throughout the period since 1982 (first diagram below), and although there was considerable fluctuation in reproductive success in the 1980s and 1990s, production since 2000 has been unusually below 10% which was not the case in earlier years (second diagram below).

67rhun   67rhun2

Feeding sites and habitat: Thorough surveys in recent winters have shown that as well as the core area of Rhunahaorine Point, feeding occurs on a range of fields south to Killean and Tayinloan.  The main feeding area at Rhunahaorine is an extensive area of improved and reseeded grassland and well as rough Juncus dominated grassland and wetland (NR7049).  Other sites include improved pasture near Auchindrain (NR717509), Killean (NR690442) and in autumn stubble fields near Tayinloan and Culfuar (NR698445 to NR698458).  As elsewhere, this flock specialises on grassland for the vast majority of the winter, but the flock will glean grain from arable fields, whilst the food resource remains to make such foraging is profitable. There have been allegations of damage to turnips in the main feeding area, but it is more likely that this results from the 400+ Greylag Geese that frequent the area. It is not clear if the establishment of feeding at Glencardoch Point further south has originated from Rhunahaorine birds or from geese wintering at Machrihanish, but the former is more likely.  There is some movement to and from pastures south of Dun Chibhich on the nearby island of Gigha, but the extent and importance of Gigha to this flock are poorly understood.  There remain many questions associated with the increase in the numbers of geese wintering on Kintyre in recent years, and there is a need to improve our present understanding of the highly complex situation regarding flock identities and movement.  Sites on Kintyre were the subject of detailed surveys in 1986/87 (Bignal 1987), 1987/88 (Batty 1988) and by the RSPB in 1993/94.

Roosting sites: A number of roosts are also used, with up to 100 using Loch Garasdale (NR7651) on a regular basis.  Neighbouring lochs are also used, and a few fly as far as Tangy Loch (NR6927) the principal roost of the Machrihanish flock, 25 km to the south (R&O 1979).  Small numbers also use Loch Gad (NR7857) 11 km from Rhunahaorine, but whether these are a discrete other group or part of the Rhunahaorine complex is not clear.  Evidently White-fronted Geese also fly over Kintyre to Grogport and Garradale and sometimes south to Lussa Loch, near Tangy Loch (P. Smith pers. comm.).  Use of the roosts is therefore very complex and probably varies through the winter.  Often under moonlight and calm conditions, the geese will remain on the feeding fields or roost in shallow pools adjacent to foraging areas and even on the sea nearby (R&O 1979)

Habitat change: None known to affect the geese.

Aircraft disturbance: Not known

Hunting disturbance: Not known, but not thought a problem.

Agricultural disturbance: Not known, but although there will undoubtedly be some; this flock has many alternative feeding areas that any disturbance is not thought to constitute a significant problem.

Site safeguard: Rhunahaorine Point is NCR SSSI and the roosts are protected as part of the Kintyre Goose Roosts SPA and Ramsar site.

SNH Natural Heritage Zones/Area: Argyll West and Islands.

Threats: Some local hunting of Greylags offer potential difficulties of disturbance, wounding and accidental killing of White-fronted Geese at this site.  There have been several instances of illegal killing of birds at this site in the 1980s, some of which have led to successful prosecutions.  There has been a succession of proposals to build wind farms in the hinterland behind the feeding areas of this flock, the flightlines of which took the birds through or very near to the proposed placing of the turbines.

Linkages with other sites: As of June 2006, there had been almost 600 resightings of 91 different marked birds on Kintyre, more than half of these from the Rhunahaorine flock involving 46 different individuals.  Of these, only 6 have been seen both in this flock and the Machrihanish group, and since many of the individuals wintering at both sites were long-stay individuals, present for many years in succession, this is strong evidence for the fact that there is very little interchange of individuals between these groups despite their size and proximity.  Those that have occurred include 21 geese caught originally at Wexford, 21 from Greenland birds caught during moult and 2 caught in Hvanneyri in western Iceland.  Of those caught at Wexford, 6 were seen once briefly in autumn staging before continuing to Wexford for the remainder of the winter.  The rest included 5 birds that remained at Rhunahaorine for one year before wintering elsewhere (including some that returned to Wexford) and 6 geese that apparently switched to Rhunahaorine as their winter quarters, remaining consistently in subsequent years.  The presence of so many Greenland marked birds caught in the southern part of the breeding range in Isungua and Eqalungmiut confirms the leapfrog migration pattern found amongst ringing recovery and resighting information from elsewhere.  The very low incidence of occurrence of birds marked at Hvanneyri in west Iceland also conforms to the pattern that most birds breeding in the southern part of the breeding range stage in the southern (rather than western) parts of Iceland during passage there.  Hence, it would appear that this flock derives mostly from breeding stock nesting in the southern part of the range, but there has been some interchange with Wexford and Islay and other resorts, but relatively little with the adjacent flock at Machrihanish.

References

Batty, P. (1988) Counts of Grey Geese in Kintyre and Knapsdale.  Unpublished report to Nature Conservancy Council, South West Region. 25pp.

Bignal, S. (1987) Counts of Grey Geese in Kintyre, Argyll 1986-1987.  Rhunahaorine and Machrihanish.  Unpublished report to Nature Conservancy Council, South West Region. 18pp.

Thompson, K. & Harding, N.J. (1994) Winter bird surveys on proposed Special Protection Areas in Scotland.  Report 3: Winter Goose Surveys in Kintyre, Wigtownshire and Flanders Moss.  Report by RSPB to Scottish Natural Heritage.