Little Grebe - Migration

Tachybaptus ruficollis

The Migration Atlas (2002) suggests that most Little Grebes disperse from their breeding area to winter elsewhere. It also states that there are still many unknowns about their migration, citing very few examples of immigration based on ring recoveries. BWP considered autumn and spring records on or near the British east coasts, especially at lighthouses, indicated immigration from the Continent.

There are no records of Little Grebes visibly migrating in Pembrokeshire, possibly meaning they pass at night but there have been none noted at local lighthouses. Diurnal records of birds on the sea at Strumble Head and Skomer and visiting ponds on Skokholm, Ramsey and most frequently Skomer, indicate dispersal at least and possibly longer distance migration as well.

Graham Rees

(Covers records up to and including 2008)

References

CRAMP. S. (Editor), 1977 – 1994. Handbook of the Birds of Europe, the Middle East and North Africa : the birds of the Western Palearctic, Oxford University Press, 9 Vols.

Spotted Redshank - autumn

Tringa erythropus

Autumn passage, between the 18th June and October, involved 41.5 % of the county total with records from Skokholm, Skomer, Grassholm, Ramsey, the Gann, upper Cleddau Estuary, Bicton Reservoir, Westfield Pill, Sandy Haven Pill, Amroth, Castle Martin, West Williamston, Fishguard Harbour, Nevern Estuary, Teifi Estuary, passing over St David’s and Crundale, coasting past Strumble Head and once at a lighthouse attraction there.

Most records referred to autumn passage during the 1960’s and in the 1970’s autumn passage included the largest gatherings yet seen in the county, viz : 20 at Hook on the 17th September 1972 and 27 there on the 12th October 1978.

Graham Rees

(Covers records up to and including 2006).

Spotted Redshank - spring

 Tringa erythropus

Spring passage, between April and the 25th May, has been small and amounted to 2.9 % of the county total record. Migrants were reported from Skokholm, Skomer, Dale airfield, the Gann and Sandy Haven Pill.

There were only two spring records in the 1960’s and none in the 1970’s. The 1980’s were notable for the bulk of the spring records, which included five at Skokholm on the 15th and 16th April 1983.

Graham Rees

(Covers records up to and including 2006).

Arctic Skua - Spring

Stercorarius parasiticus

The Arctic Skua has been sparse in Pembrokeshire waters during spring, with one to three per annum being the norm during the period 1958 to 2003, passing between the 4th April and the 30th June. Four in 1998, six in 1996, eight in 2002 and 10 in 1993 exceeded the norm. Records came from Tenby, Broad Haven (S), St Govan’s Head, West Blockhouse, St Ann’s Head, Skokholm, Skomer, The Smalls, St Bride’s Bay and Strumble Head.

Graham Rees.

(Covers records up to and including 2007).

Red-throated diver - passage

Gavia stellata

A marked autumn passage of birds travelling from north to south has been recorded since at least 1980, spanning the months August to December, though singles were recorded in 2 years on the 11th July and once on the 3rd July.

This movement has been well documented at Strumble Head. August records were confined to the latter part of the month, 19th – 31st, totalling just six birds over the period 1980 – 2006.The main passage was between October and December and is represented below in graphical form. These are the mean annual values calculated from the total number of birds recorded for the period 1980 to 2006, grouped into six day intervals.

Only once in 27 years did the passage continue into January, when 40 passed on the 6th in 1991, thereafter no movement being detected during that month. The number of birds passing on any one day was generally small but over 30 was recorded five times in four different years, the maximum being 44 on the 4th December 1993.

The December peak was obscured in some years, with passage ceasing during gales. It is not known whether these held up birds within the comparative shelter of Cardigan Bay which continued their migration when the wind moderated, or the gales displaced birds from further south to seek shelter in the Bay, or possibly whether both reactions took place.

A passage of smaller volume than in the autumn has been noted in spring, March to 30th May. This has not been well documented but has involved birds passing westwards off St Govan’s Head, northward past the offshore islands of Skokholm and Skomer and eastwards past Strumble Head.

The Red – throated Diver has only been recorded in Pembrokeshire once in June, when two were seen at Skomer on the 18th in 2003.

Red-throated diver - ages

Gavia stellata

Very few observers have reported whether their sightings involved adults or immature birds, perhaps not surprisingly considering the circumstances in which they are often seen. However in the autumn it is easy to differentiate those in full summer plumage and those showing traces of summer plumage, from those in winter and juvenile plumage.

This was recorded systematically at Strumble Head during autumn passage between the years of 1980 and 2008. The proportion showing signs of summer plumage was 91 % in September, 50 % in October and 3 % in November (latest on 23 November), the total number of birds examined being 483, 588 and 533 respectively. This clearly indicates that adults pass earlier than the bulk of younger birds.   

Graham Rees

(Covers records up to and including those for 2006).

Snow Bunting - migration

The Snow Bunting has a circumpolar breeding distribution, inhabiting the treeless expanses of the Arctic, extending south to areas of Norway and Scotland. Partially migratory, many winter far south of the breeding range. Most occurring in Britain have been of the Icelandic race P. n. insulae but the nominate race P. n. nivalis has been recorded in lesser numbers.

Six single Snow Buntings are on record for Pembrokeshire between the years 1859 and 1914, indicating that the species did not loom large during the specimen collecting era, which is perhaps significant considering their striking appearance. Lockley et al (1949) noted that the Snow Bunting was “a regular visitor to Skokholm in October and November but only once seen in spring”.

For the whole county there followed records in 17 years between 1953 and 1969, in 14 years between 1970 and 1989 and in every year bar one between 1990 and 2007.The majority, 86 %, were recorded in the autumn, between mid September and December, the earliest being on the 11th September. Of these 50 % were recorded in October.

Mostly single birds were involved but parties of up to 10 were sometimes encountered, with up to 15 seen at Ramsey, up to 17 at Skokholm and up to 38 at Strumble Head. The mean county autumn total was 9 per annum, excluding exceptional numbers recorded in 1996 and 1999.

 A total of 172 was recorded in 1999, of which a passage total of 115 on 16 dates was logged at Strumble Head. A total of 209 was recorded in the autumn of 1996, 160 of them spread over 10 dates passing Strumble Head.

 Snow Buntings have been recorded in the autumn at Pen Morfa, Dinas Island, Strumble Head, Garn Fawr (Pen Caer), Pen Brush, Trefin, Abereiddi, Trwyn Llwyd, St David’s airfield, Treleddyn, St David’s Head, Porth Clais, Ramsey, South Bishop, Solva, Newgale, Nolton Haven, St Bride’s, Martin’s Haven, Wooltack Point, Skomer, Grassholm, The Smalls, Marloes Beach, Skokholm, Gann,  Dale airfield, Kete, St Ann’s Head, Freshwater West, Castle Martin ranges, St Govan’s Head, Stackpole, Greenala and Garron.

 It seems that Snow Buntings can be encountered anywhere in coastal areas during autumn passage. Single birds at Carn Ingli on the 24th October 2005 and at Foel Eryr on the 28th November 1985 are the only inland records at this time of the year, perhaps reflecting the paucity of observers away from the coast at passage time.

A small and erratic spring passage has been detected in coastal areas, with variously one to three birds at a time noted during March and April, in 14 years between 1958 and 2006. Single birds were also recorded at Manorbier on the 26th May 1991 and at Strumble Head on the 5th June 1959 and 19th August 2002, the latter “captured” on video.

References

LOCKLEY. R. M, INGRAM. C. S. and SALMON. H. M.1949. The birds of Pembrokeshire, West Wales Field Society.

Red-necked Grebe

Podiceps grisegena

A scarce winter visitor and passage migrant.

The Red – necked Grebe breeds mainly in fresh water habitat, in the temperate Palearctic and Nearctic, mostly wintering on tidal waters.

In Pembrokeshire, Mathew (1894) noted that the Red–necked Grebe had been killed several times at Pembroke Mill Pond. Thereafter records were more specific. A total of 102 birds were recorded in 44 years between 1898 and 2006, observer cover being greatest from the 1980’s. It seems that the species has been a regular visitor but more have been seen in some years than in others, mostly one to four in a year but six were noted in 1987 and 1997, 10 in 1988 and 16 in 1996.

Annual totals on record 

They have been noted around the outer coast at Newport Bay, Fishguard harbour, Solva, Newgale, Druidston, Little and Broad Haven (N), Martin’s Haven, Wooltack Point, St Ann’s Head, Giltar and Tenby, on the Teifi Estuary and in most parts of the extensive Cleddau Estuary as far upstream as Little Milford. They have also occurred on fresh waters at Bosherston, Llys y fran Reservoir, Heathfield Gravel Pit, Pen Beri Reservoir, Treginnis, Slate Mill Reservoir, Bicton Reservoir, Westfield Pill and Crickmarren Pond. Additionally singles were recorded once at Skomer, twice at Skokholm and on six occasions flying past Strumble Head, which were considered to be active migrants.

They were mainly recorded in the periods of January to March, 55 %, and October to December, 40 %, but also seen four times in April, once in May (at Skokholm on the 21st 1997), once in July (at Dale on the 30th 1948) and six times in September.

Graham Rees

( Covers records up to and including 2006 ).

Chaffinch - 2008 migration

Many Chaffinches from northern Europe, particularly Scandinavia, migrate in the autumn down the Continental west coast, crossing either over the southern North Sea or the English Channel to winter in Britain. Some continue through Britain to Ireland.

Lockley et al (1949) described Chaffinch migration of tens of thousands coming down over Cardigan Bay to strike the northern and western coasts of the county during October.

Betts (1992) noted large movements through Skokholm in October and November, including 3,200 passing on the 22nd October 1966 and 2,000 grounded in fog on the 26th October 1988.

A total of 11,600 were logged passing Strumble Head during 12 days of observation between the 16th October and the 22nd November 1981. Peak passage involved 2,160 on the 24th October and 2,590 on the 1st November.

The Pembrokeshire Bird Report for 1986 recorded many thousands passing Strumble Head between the 4 October and the 12 December. It added it would have taken an army of observers to count the visible birds but many more were heard that were too high to see.

The volume of passage during October to November diminished thereafter. Peak autumn totals at Strumble were 2,405 in 1999 and 2,711 in 2007. Peaks at Skomer were 3,500 in 1993 and 4,850 in 2008.

At least 1,000 passed over the St David’s peninsula on the 24th October 2002. 1,000 coasted at Pen Anglas on the 15th November 2007. 1,350 passed Pencarnan in half an hour on the morning of the 23rd October 2009.

Flocks have sometimes temporarily accumulated in coastal regions during autumn passage time e.g. 400 at Marloes on the 24th November 1991 which soon moved on.

Fragmentary as the available records are, they evidently indicate that considerably fewer migratory Chaffinches have been reaching Pembrokeshire since the massed movements of the1940’s to 1980’s period.

Lockley (1957) described a strong return passage during March and April but this has not been detected since, other than a few Chaffinches appearing on the offshore islands at this season.

Graham Rees.
(Covers records up to and including 2008)

References
BETTS. M. 1992. Birds of Skokholm, BioLine, Cardiff.
LOCKLEY. R. M, INGRAM. C. S. and SALMON. H. M.1949. The birds of Pembrokeshire, West Wales Field Society.
LOCKLEY. R. M. (1957). Pembrokeshire, Robert Hale, London.
REES. G. H. (Ed). Pembrokeshire Bird Reports, 1981 – 1986, West Wales Naturalists Trust.