Little Egret - 1994

 Occasional visitor

The first Little Egret was seen at Goodwick in November 1909, the next at Dale on 25 May 1938 and on 8-12 May 1949 ( Lockley et al. 1949). Thereafter it remained occasional but has occurred more frequently in recent years (see Table 3).

Most occurrences up to the 1980s were in the spring months of April to June, although long stayers had overwintered. However, in the 1990s Little Egrets have occurred more in the late autumn, October to November, with a greater tendency to overwinter. Most have been single birds but three together have been noted and seven were present in the Cleddau Estuary in early 1993. Most records are from the estuaries of the Cleddau, Nevern and Teifi but they have occurred briefly elsewhere, for example at St David's on 23 November 1991 and at Fishguard on 22 December 1992.

Cattle Egret - 1994

Vagrant

A single bird appeared at Haroldston Chins on 11 December 1980, which moved to Redstock by 13 December and Stackpole and Bosherston Pools by 16 December, remaining until 16 January 1981 ( J.W. Donovan, W.C. Philpin, F. and M. Scriven et al.). A different bird was at Crundale from 12 to 14 April 1981 (J.W. Donovan, G.H. Rees et al.).

Night Heron - 1994

Rare visitor. Recorded from March to May and from October to December

Mathew (1894) records single birds on four occasions, in 1857 and 1868 at Pembroke Mill Ponds and another undated at Lamphey, while one was shot from a group of three roosting near St David's Cathedral. Lockley et al. (1949) added a record of an immature shot near Pembroke in 1919. There were two subsequent records, an adult at Skomer from 12-16 May 1979 and an immature at Bosherston Pools on 11 October 1981, until between March and April 1990 when singles were recorded at Bosherston Pools, Westfield Pill, Rosemarket, St Ishmael's, Trecwn and Abermawr, with two at Skomer and four at Pentood. Some of these birds remained into April, and were part of a major invasion of south-west Britain following a period of strong southerly winds from southern Europe.

Little Bittern - 1994

Rare visitor

One was recorded, but no date was given, from Merlin's Bridge by Mathew (1894), who also mentioned that one in the Cawdor collection at Stackpole had been procured in the county. Lockley et al. (1949) noted singles off the Pembrokeshire coast in October 1899, shot near Fishguard in about 1916 and "taken" near Solva "many years ago".

One was found dead at Broad Haven on 26 April 1964, one seen at Sandy Haven on 18 April 1970 and another at Dowrog on 3 May 1983 

American Bittern - 1994

Vagrant

Mathew (1894) records one shot near St David's in October 1872. Lockley et al. (1949) report a male shot by Dr Mills on 11 December 1905 as having been obtained at Dale, but Lloyd examined the specimen and noted in his diary that it was labelled from Trewellwell. One was seen on Abermawr beach, Ramsey, on 19 October 1946 (Davies and Lockley 1947).

Bittern - 1994

Sparse winter visitor. Not recorded from July to September

George Owen (1603) refers to Bitterns breeding in the "bogges" of Pembrokeshire. Mathew (1894) regarded the Bittern as a winter visitor, quoting many records including 13 killed in one week during the hard winter of 1842. Lockley et al. (1949) noted that two (one shot) were at Dowrog on 26 June 1909, a date suggesting possible breeding. Lockley (1957) regarded the Bittern as "almost a regular visitor" in winter and that remains the position today, with occasional sightings in most years from a variety of wetland sites such as the Pentood Meadows, Dowrog and Llysyfran. More occur when they are frozen out of their winter quarters further east, the most recent incursion being in December 1981 when singles were seen at Pentood, Thornton and St Ishmael's, with up to four at Bosherston Pools.

Shag - 1994

Breeding resident and passage migrant

Mathew (1894) noted colonies of Shags at Ramsey, St Margaret's Island, Caldey and Elegug Stacks, Lockley et al. (1949) adding Skomer, Skokholm, Grassholm and Middleholm. 

In 1969, during Operation Seafarer, 121-126 nests were found. During 1985-1987 the Seabird Register found 96 nests. Colonies vary in size, from single nests to between 25 and 37, the largest being found at Grassholm, St Margaret's Island and Middleholm, though numbers do not remain stable.

More maritime than the Cormorant, Shags can be found feeding in deeper water all around the Pembrokeshire coastline and islands as far out as the Smalls.  They regularly fish in the Cleddau Estuary, penetrating upstream as far as Beggar's Reach, occasionally further, or in the side pills during prolonged stormy weather.

Shags are seen throughout the year but ringing has shown that there is widespread dispersal of breeding birds, especially the young. Some move towards North Wales but most towards the Bristol Channel. A few reach the English Channel, the Bay of Biscay and Spain.  A southwards passage through St George's Channel occurs each autumn and ringing recoveries indicate that these birds come from at least as far as Gwynedd.   

Fieldwork 1984-88 (based on 478 tetrads)

Red = breeding confirmed = 28

Orange = breeding probable = 4

Total tetrads in which registered = 32 (6.7%)

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

Cormorant - 1994

Breeding resident

Mathew (1894) noted Cormorant colonies at Ramsey, Skomer, Lydstep Head and Pointz Castle, Lockley et al. (1949) adding St Margaret's Island, St Bride's Stacks, Pwll Deri and Newport Head.

In 1969, during Operation Seafarer, 378-388 pairs were found breeding, while the Seabird Register of 1985-1987 found 362 pairs, so the population has remained fairly stable despite variation in the sizes of individual colonies. Cormorants are seen throughout the year with the colonies usually occupied from February to September, ranging from single pairs breeding on cliff sites to the largest colony in Wales at St Margaret's Island, which held 322 nests in 1973, but 230 pairs in most years since (see Table 2). Mathew (1894) recorded nesting in trees at Slebech.

Ringing at St Margaret's Island has shown that some birds remain in Pembrokeshire waters through­out the year but others, mainly immatures, move up the Bristol Channel during the winter, or along the length of the English Channel and into the Bay of Biscay as far as the Iberian peninsula. Some pass inland to the Thames Valley, a few reach Ireland and North Wales and one has been recovered in Holland. Additionally, each autumn strings of up to 20 birds are seen passing down through the southern Irish Sea and St George's Channel from the north, and Irish‑bred birds have been noted at St Margaret's Island.

Cormorants fish extensively in the shallow bays around the Pembrokeshire coast, penetrate all the estuaries and rivers and regularly frequent the larger inland waters such as Llysyfran reservoir, besides visiting quite small pools on an opportunistic basis. Winter roosts of up to 47 birds include several breeding sites but they also roost elsewhere, notably in trees at Llysyfran reservoir, Slebech and Femhill.

Fieldwork 1984-88 (based on 478 tetrads)

Red = breeding confirmed = 13

Orange = breeding probable = 1

Total tetrads in which registered = 14 (2.9%)

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

Gannet - 1994

Breeding resident

The only breeding site for the Gannet in Wales is on Grassholm. Williams (1978) provides a résumé of the history of the colony which seems to have been established shortly before 1860, when 20 pairs were present, though Gurney (1913) suggests birds may have been present as early as 1820.

They were beset by problems during the early years, mainly from egg collectors, while in 1890 members of the Cardiff Naturalists Society, who were camping on the island at Whitsun, witnessed a party of naval and military officers from Pembroke Dock shooting Gannets and taking and smashing eggs. The miscreants were brought before the bench at Haverfordwest in August of that year and fined a total of £22.17s. in what the magistrates described as "a somewhat novel case ... but it was also a charge that could not be passed over lightly."

The growth of the colony aroused the interest of a succession of ornithologists, resulting in a series of nest counts, initially made by eye, then by photographs taken on the ground first by Acland and Salmon (1924), followed by the first aerial survey in 1956 (Lockley 1957); this remains the standard census method (see Table 1). Colony growth has not been uniform, Nelson (1978) demonstrating that Grassholm must have exported breeding birds in the 1960s but imported them in the 1920s and 1970s.

A fresh count of the Grassholm gannetry is clearly overdue as observations show a continued advance by the Gannets. The days are gone when visitors stood on the summit of the island viewing the colony spread below; the high point is now fully occupied by breeding birds which are advancing southwards across the island. The RSPB, who have owned Grassholm since 1948, have had to prohibit landing at two points in order to minimise disturbance to birds nesting in their vicinity, it being a matter of conjecture how long it will be before the sole remaining landing point is also occupied by breeding birds.

With apparently plenty of food to support their ever increasing numbers and few enemies the Grassholm Gannets have little to fear save for man­made hazards. The most obvious of these is that posed by entanglement in nylon lines and netting. The Gannets gather prodigious quantities of nesting material, normally seaweeds with the addition of grasses pulled from near the colony. However, anything floating in the sea which can be carried is likely to be incorporated into the nest. For the past two decades this has included nylon, and some nests can be bright orange in colour, so significant is the quantity. Adults and chicks can become entangled and deaths occur, either through birds being anchored to their nests or by becoming so entangled that they cannot fly properly.

Over 5,000 Gannets were ringed on Grassholm, largely by the staff of the Skokholm Bird Observatory, up until the late 1960s. There have been recoveries from as far apart as the Faeroes and Senegal, with most immatures following the traditional route south to west African waters where some remain for the first two years of life. Most adults do not travel so far but remain in home waters throughout the winter.

Large passages occur off Strumble Head in the autumn which probably include many birds from colonies other than Grassholm. Passage peaks in August, the average rate from 14 counts made in 1980 and 1981 being 180 birds per hour, the maximum 1,700 in five hours on 25 August 1980. An albino recorded at Strumble Head on 15 September 1985 was also seen passing Towan Head, Cornwall, on 16 September 1985, indicating through passage.

Although fairly sparsely distributed inshore during the winter months, typically less than ten at any locality, onshore gales temporarily push greater numbers towards the land; for example, up to 100 were seen at Strumble Head on 2 January 1988. Grassholm is usually deserted from about late October and reoccupied in January.

Fieldwork 1984-88

Red = breeding confirmed

Orange = breeding probable

Yellow = breeding possible

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

Leach's Petrel - 1994

Probably a regular visitor in variable numbers. Not recorded in January, March, April or August.

Mathew (1894) stated that "it is not very rare as a visitor in stormy weather". Lockley et al. (1949) expressed surprise at this statement for they knew of only one occurrence "in the last fifty years". Saunders (1976) stated that the Leach's Petrel was normally "a rare storm driven visitor to the county" but drew attention to an exceptional wreck in October/ November 1952, when 88 dead and 5 live birds were noted along a 0.5 km stretch of Newgale Beach (Boyd 1952).

Post-Lockley et al., and the 1952 wreck apart, Leach's Petrels were recorded on only five occasioris offshore up to 1980, while one or two were found visiting Storm Petrel colonies at Skokholm in May to July of the years 1966, 1976-1978, 1980 and 1989. Single birds were noted at Fowborough in the Cleddau Estuary on 6 February 1983 and at the Smalls on 24 September 1983, but regular seawatching at Strumble Head since 1980 has indicated that a few occur most years, probably every year. Up to ten are usually seen between September and November and they become more numerous during north-west gales; for example, 109 passed Strumble Head on 13 September 1988. Severe gales in late December 1989 resulted in singles being seen at Newgale and Wiseman's Bridge and at Angle Bay six were seen

Storm Petrel - 1994

Breeding summer visitor. Not recorded in January and February.

Storm Petrels are difficult birds to survey, since they nest in crevices, often on inaccessible scree slopes. However, 6,000 pairs were estimated as breeding at Skokholm in 1969. A survey carried out at Skokholm using a light amplifier, conducted in 1990, resulted in a distribution of colonies little changed from that of a 1967 survey. Recent work at Skomer suggests probably less than 200 pairs breed on that island. Three nests were found on North Bishop in 1985 but it was suspected that there were more. Breeding birds were established on the Green Scar in 1928 and 1930, were probably breeding on Middleholm and have been seen in suitable terrain at St Margaret's Island and on Stack Rocks in St Bride's Bay in the past. It is possible they nest in scree at the foot of some mainland cliffs where they have been seen leaving crevices in the breeding season.

The imprecision of census results obstructs the detection of population trends. There are no mammalian predators at their known nesting localities but they are predated by gulls, by Little Owls at Skomer and formerly at Skokholm, and they occasionally die from other, sometimes bizarre, causes; for instance, a bird died when it became ensnared in the seed head of lesser burdock at Skokholm.

Much of what is known of the breeding cycle of the Storm Petrel is derived from work carried out at Skokholm, first by Lockley (1932), followed by Davis (1957) and Scott, who was resident from 1966 to 1969 (Scott 1970). They arrive in home waters in April, occasionally in March, and most depart by October. Autumnal gales, particularly in early September, can blow considerable numbers inshore; for example, over 100 were seen at Strumble Head on 3 September 1983. Extensive mist netting and ringing at headlands indicates a strong, regular through passage of non-breeding birds late in the breeding season. The breeding population appears to use the Irish Sea only sparingly as a feeding area, but regularly frequents the Bristol Channel and, even more so, the southern Celtic Deep.

 

Fieldwork 1984-88

Red = breeding confirmed = 3

Total tetrads in which registered = 3 

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

Wilson's Petrel - 1994

Vagrant

Wilson's Petrel is an Antarctic bird which visits the north Atlantic outside its breeding season (Cramp 1977). One seen from the Rosslare to Fishguard ferry, a few kilometres off Strumble Head, on 12 September 1980 (B.A.E. Marr, W.E. Oddie) was only the fourth record in British waters this century. Singles were then seen at Strumble Head on 3 September 1986 (R.H. Davies, G.H. Rees, G.J. Walker) and 6 September 1990 (P. Bristow, R.H. Davies, G.H. Rees et al.). All occurred after south-west gales and as recent pelagic trips have shown that Wilson's Petrels are regular in the south-west approaches of the British Isles in the late summer (Colston et al. 1991) it is likely others will be seen in Pembrokeshire when suitable weather conditions and season coincide.