Shag - 1949

Phalacrocorax aristoltelis aristotelis

Common resident, more numerous than Cormorant.  Mathew givew the following breeding stations: Ramsey, Skomer, St Margaret's Island, the channel side of Caldey, and in a cave on the west side of the great Stack.   A pair usually breeds at Skokholm and others at Grassholm and Middleholm, and along the whole coast there are scattered pairs.

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

Shag - 2003-07

Shags are essentially inshore feeding birds that prefer rocky coastlines.  Their nests are well-distributed around Pembrokeshire, with concentrations on the offshore islands. 

Despite being relatively common around the coastline, breeding Shags are not very easy to count accurately because they nest in deep crevices and so can be almost invisible.  Also some sites are not commonly visited or counted. The population has fluctuated considerably in the last fifty years with a low point during the late 1980’s and early 1990’s. The reasons for that decline are unknown but it was seen in all areas of the county. The Sea Empress oil spill in 1996 caused the death of a small number of Shags, mainly around the entrance to Milford Haven and around the south coast of the county.  The counts in 2008 were the highest since the early 1970’s and reflect high breeding success during recent years.

Only about 200 pairs currently breed in the county. The overall impression is, however, of a small but vibrant population which is doing well in the first decade of this century.

Steve Sutcliffe.

 

Fieldwork 2003-07 (based on 490 tetrads)

Red = breeding confirmed = 26

Orange = breeding probable = 3

Yellow = breeding possible

Total tetrads in which registered = 29 (5.9%)

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

Shag - 1970s breeding

Red = breeding confirmed

Orange = breeding probable

Yellow = breeding possible

Shag - 1980s winter

The BTO winter atlas showed that Shags were present in all coastal and two estuarine 10km squares during the winters of 1981-82, 1982-82 and 1983-84.

The colour for each 10km square represents 1-10 birds seen in a day.

Graham Rees

Shag - 1894

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

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