Swift - 1949 status

Apus apus apus

Numerous summer visitor, breeding in castles, chapels, and tall buildings, also coastal cliffs (Caldey).  considerable passage towards orth-west and Ireland during May.

R.M.Lockley, G.C.S.Ingram, H.M.Salmon, 1949, The Birds of Pembrokeshire, The West Wales Field Society

Swift - 2003-07

Swifts nest in cavities in buildings and in Pembrokeshire in the cliffs of the south coast.

Those nesting in cliffs apart, Swifts in Pembrokeshire are entirely reliant on buildings for nest sites. The amount of renovation that has taken place since the 1980’s has made an increasing number of buildings no longer accessible to Swifts and new constructions have also proved to be unsuitable. It could reasonably be expected, therefore, that the breeding population has decreased over the past 20 years. Comparing the confirmed and probable breeding registrations combined, indicates a 48% decrease between 1984-88 and 2003-07.  This is consistent with the BBS index showing a 47% decrease in Wales as a whole between 1994 and 2007. The possible breeding category was ignored when interpreting the results of both local surveys,

Swifts being such mobile birds when feeding, they can be seen almost anywhere without this providing any clue to their nest site. Although no good method of assessing population has been evolved on a county scale, an estimate was made at the end of the 1984-88 survey by noting how many were entering buildings at some reasonably well-watched colonies and using this as guidance. The result was a rough estimate of about 2,000 pairs. Applying the distribution decrease to this figure suggests there may have been less than 1,000 pairs by the end of 2007. However this assessment makes no allowance for any decrease occurring within the surviving distribution, something which has not been quantified. It could well be that the number breeding in Pembrokeshire has dipped below 1,000 pairs.

 Graham Rees

 

Fieldwork 2003-07 (based on 490 tetrads)

Red = breeding confirmed = 39

Orange = breeding probable = 13

Yellow = breeding possible = not included

Total tetrads in which registered = 52 (10.6%)

Swift - 1994

Breeding summer visitor and passage migrant. Not recorded from November to February 

Mathew (1894) regarded the Swift as a summer visitor, local but numerous in places, and noted breeding on inland crags. Lockley et al. (1949) called it a numerous summer visitor breeding in castles, chapels and tall buildings.

Although the majority of today's Swifts breed in buildings, natural sites are used in the cliffs at Stackpole Head, St Govan's Head and Stack Rocks (Flimston), as were others at Linney Head and Caldey Island in the past. The availability of man-made sites must be limiting, and an upsurge in building renovation in recent years, as well as the construction of new buildings that do not permit access to Swifts, makes it probable that they are less numerous than they used to be. Assessing the size of the population is problematical as their nests are not readily visible. Some idea can be gained by watching how many enter buildings or by noting the numbers screaming around the colonies during calm evenings. Using such methods, it is evident that considerable numbers breed in towns such as Tenby and Haverfordwest, that they are less numerous in other towns such as Fishguard and Narberth and that smaller colonies exist in pockets, as at Wiston Church, Gelly and Boncath. Linking rough estimates of this kind with the Breeding Birds Survey, the total population seems to be of the order of 2,000 pairs, but this may well prove to be an underestimate.

The first Swifts usually arrive in April, with the bulk following in May. Earlier birds have been seen from 14 April, and six were at Orielton on 21 March 1960 and one at Skokholm on 26 March 1953. They continue to pass northwards throughout May and into June. One was seen against the lantern of the Smalls lighthouse on the night of 17 May 1984.

It is difficult to decide whether the Swifts seen over the offshore islands in July are migrants or feeding birds from mainland colonies. Those found dead from collision with the lantern of the South Bishop lighthouse at night in July might indicate passage, but they could have been locally breeding birds which were asleep on the wing when forced down by bad weather. Swifts depart the colonies suddenly and en masse during the first three weeks of August, when they can also be seen flying in off the sea along the north and west coasts, and they were recorded killed at night at the South Bishop lighthouse on 6 August 1975 and 25 August 1976. A few are seen in September with occasional stragglers into October, the latest recorded being on 28 October.

Fieldwork 1984-88 (based on 478 tetrads)

Red = breeding confirmed = 89

Orange = breeding probable = 11

Total tetrads in which registered = 100 (20.9%)

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

Swift - 1970s breeding

Red = breeding confirmed

Orange = breeding probable

Yellow = breeding possible

Swift - 1894

Species account from M Mathew, 1894, "The Birds of Pembrokeshire and its islands"

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