Blackcap - 1994

Breeding summer visitor, passage migrant and winter visitor

Mathew (1894) classified the Blackcap as a summer visitor that was far from common, with a few pairs in the north-east of the county, also noting that it was "stated to be common in the extreme south". Lockley etal. (1949) regarded it as a "fairly common" summer resident which appeared on the islands on spring migration but rarely in autumn.

Today they breed throughout Pembrokeshire and appear to be equally common in all parts of the county. An average density of 20 pairs per tetrad, based on singing birds, suggests that the total breeding population is about 7,000 pairs. They arrive at the breeding grounds throughout April and early May, whereas migrants pass through the islands from 26 March to mid-June, most of them in April. Autumn passage has been noted from 23 July to 30 November with a distinct peak in October.

Blackcaps regularly winter here, though the birds involved are not neccessarily part of the local breeding stock. Wintering birds obscure the validity of early and late passage dates, but, as they do not normally winter on Skokholm and Skomer, island data has been used to delineate migration periods.

Fieldwork 1984-88 (based on 478 tetrads) 

Red = breeding confirmed = 86

Orange = breeding probable = 248

Yellow = breeding possible = 5

Total tetrads in which registered = 339 (70.9%)

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Garden Warbler - 1994

Breeding summer visitor and passage migrant. Not recorded in January, March and December

Mathew (1894) found the Garden Warbler to be a scarce summer visitor, whereas Lockley et al. (1949) considered it widely distributed but local.

Today they breed commonly, their distribution showing a heavy bias towards the eastern half of the county (see map). An estimated average density of ten pairs per tetrad suggests a total breeding population of about 2,000 pairs. They arrive back on the breeding grounds from early May and become increasingly difficult to find from mid-August.

Up to ten Garden Warblers at a time occur on the islands and in scattered coastal areas from 23 April to 25 June, with occasional earlier birds from 6 April onwards, and again between 17 July and 28 October. They have been noted at the lantern of the Smalls lighthouse at night in May, August and September. Late birds were at Skokholm on 2 November 1968 and at Picton on 27 November 1977. A Garden Warbler seen at Pembroke on 28 February 1976 may well have overwintered, and another was trapped for ringing at Pwllcrochan in February 1992.

Fieldwork 1984-88 (based on 478 tetrads) 

Red = breeding confirmed = 47

Orange = breeding probable = 133

Yellow = breeding possible = 13

Total tetrads in which registered = 193 (40.4%)

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Whitethroat - 1994

Breeding summer visitor and passage migrant. Not recorded in November

Whitethroats were classed as common summer residents by Mathew (1894) and Lockley et al. (1949) and this was the situation until 1967. In 1968 only about 30% of the population returned to breed. This depletion was noted throughout Britain and has been attributed to poor survival on the Whitethroats' drought- stricken wintering grounds of the Sahel (Sharrock 1976). Recovery has been gradual and the population at the time of the 1984-1988 Breeding Birds Survey, with an average density of 20 pairs per tetrad, was probably about 8,000 pairs.

They generally arrive in Pembrokeshire between the middle of April and early June, but in some years occur from the 5 April onwards, with one at Fishguard on 23 March 1956. Their passage is dramatic, with thousands passing in a series of waves, particularly noticeable on the islands and headlands. Some diurnal falls are spectacular, such as the estimate of about 500 at Skokholm on 22 May 1959. They have been noted at night at the lanterns of the South Bishop and Smalls lighthouses.

They pass through the islands and coastal areas again between late July and 31 October, but are less numerous than during the spring passage.

A male was a regular visitor to a Haverfordwest bird-table from 20 December 1990 to April 1991.

Fieldwork 1984-88 (based on 478 tetrads) 

Red = breeding confirmed = 137

Orange = breeding probable = 248

Yellow = breeding possible = 21

Total tetrads in which registered = 406 (84.9%)

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Lesser Whitethroat - 1994

Breeding summer visitor and passage migrant. Not recorded in January, February and December

Although Mathew (1894) did not encounter the bird, he does include it on the strength of records at Lamphey and Dale, though Lockley et al (1949) considered these records to be dubious, noting only a few scattered occurrences, which included breeding near Llangwm in 1932, stating that the Lesser Whitethroat was a scarce migrant. Lloyd found them in each of the years from 1927 to 1931, and strongly suspected breeding at Bosherston and Tenby. They were recorded with increasing frequency from 1952 onwards, breeding being suspected at Keeston in 1965 and proved at Roch Bridge in 1974. A few pairs were reported breeding at three localities in 1977 and 1981. The Breeding Birds Survey of 1984-1988 was conducted at a time when Lesser Whitethroats became strong colonists. About 70 pairs were found during the period (see map), 60% of which were in the confirmed breeding or probably breeding categories. They are found in scrubby areas, sometimes nesting in the same place for a year or two before disappearing.

Lesser Whitethroats have also become more frequent spring migrants, with birds passing through coastal districts usually between 15 April and 5 June. One was at Upper Ripperston on 25 March 1990 and another at Dale on 26 March 1984. They remain sparse on autumn passage, with just a few occurring between 12 August and 31 October, with one at Skokholm on 3 November 1927.

Fieldwork 1984-88 (based on 478 tetrads) 

Red = breeding confirmed = 15

Orange = breeding probable = 46

Yellow = breeding possible = 8

Total tetrads in which registered = 69 (14.4%)

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Barred Warbler - 1994

Rare visitor

The first Barred Warbler recorded was at Skokholm on 12 September 1956, since when 24 juveniles have been recorded in 16 years between 1960 and 1992, 70% of them on the offshore islands of Skokholm, Skomer and Ramsey. All mainland records have been from the outer coast, at Tenby, Pennally and Strumble Head, apart from one at Uzmaston on 5 September 1984. Dates of occurrence extend between 26 August and 21 November, with just over half between 13 and 25 September.

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Sardinian Warbler - 1994

Vagrant

A skulking Mediterranean species that has been recorded in Britain fewer than 30 times, one of which was at skokholm on 28 October 1968 (C.Britton).

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Sub-Alpine Warbler - 1994

Vagrant

Single birds were seen at Skokholm on 1 October 1953, 3 May 1970, 7 June 1976, 11 May 1990 and 15 May 1992 and at Skomer on 20 April 1971, 19 April-8 May 1985, 20 May 1986, 26-27 March 1989, 3 and 26 May 1990 and 14 and 22 May 1992.  A Mediterranean species that winters in sub- Saharan Africa (Cramp 1992) it sometimes over­shoots its range during spring migration. It inhabits dense scrub and is often secretive, so may be overlooked in the extensive cover of the mainland.

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Dartford Warbler - 1994

Vagrant

Single birds were seen on Skomer on 14 September 1971 (P. Corkhill) and at Skokholm on 1 and 2 June 1981 (G.G. Gynn). They breed as near as Hampshire and Dorset, where they inhabit heathy areas similar to parts of Pembrokeshire. However, the south of England is at the northern limit of their range, the majority residing in a much drier climate, suggesting that Pembrokeshire might be too wet for them to colonise.

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Melodious Warbler - 1994

Scarce but near annual passage migrant

First recorded at Skokholm from 3 to 12 October 1955, the Melodious Warbler has since been recorded in 27 years up to 1992. Most were single birds on the offshore islands of Skokholm and Skomer, though up to three have occurred at the former locality, in the periods 23 May to 29 June and 12 July to 23 October, being eight times more numerous in the autumn. Elsewhere, they have occurred at Ramsey on 12 September 1973, at Goodwick Moor on 22 August 1983, at Haverfordwest on 12 June 1987 and at Strumble Head from 11 to 14 October 1988.

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Icterine Warbler - 1994

Scarce passage migrant

Mathew (1894) recorded a singing bird at Stone Hall in 1886 which was either an Icterine or a Melodious Warbler. However, the first specific identification of Icterine Warbler was made at Skomer on 30 May 1959 (N. Pratt and J.W. Donovan). Since then, up to two together have been recorded in 23 years. These have been on the islands of Skomer and Skokholm between 24 April and 28 June or between 21 August and 7 October, apart from one at Martin's Haven on 16 June 1986. Most records are from the autumn, mainly in September, as might be expected from a species which migrates from northern and central Europe to winter in Africa.

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Booted Warbler - 1994

Vagrant

The Booted warbler is a rare vagrant to Britain from Asia, and the first record for Wales was at Skokholm on 25-28 September 1993 (M.Betts, J.W.Donovan et al).

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Olivaceous Warbler - 1994

Vagrant

One caught and ringed at Skokholm on 23 September 1951 (P. Conder et al.) was the first British record of a species that nests no closer than Iberia and Greece. It remained on the island until the Observatory closed on 3 October, observers being treated with views at ranges down to two metres as it perched on top of the bracken.

Donovan J.W. & Rees G.H (1994), Birds of Pembrokeshire

Update on Monday, February 10, 2014 at 5:48PM by Pembrokeshire Avifauna committee

The following records have now (1998) been reassessed by the Committee and are no longer considered acceptable, the decisions in respect of those in 1951 and 1956 having been confirmed by the BOURC:

1951 Pembrokeshire Skokholm 23rd September to 3rd October (Brit. Birds 46:191-192 plate 27)