Sunday, August 11, 2013 at 8:53AM Turdus viscivorus viscivorus
Common resident. rare on islands except Caldey where it breeds. Has bred Ramsey. Almost wiped out by winter of 1946/7, but breeding very sparsely 1948.
R.M.Lockley, G.C.S.Ingram, H.M.Salmon, 1949, The Birds of Pembrokeshire, The West Wales Field Society
Sunday, May 13, 2012 at 6:04PM The 1984-88 survey found Mistle Thrushes to be more numerous in the south and north east of the county than elsewhere. The 2003-07 survey shows a much more even distribution across the whole area, other than remaining thinly spread in the far west, over all amounting to a 29% increase. The BBS calculated a 6% increase in Wales between 1994 and 2007. Applying this to the 2003-07 records for Pembrokeshire suggests a breeding population of about 1,900 pairs compared to the estimate of 1,400 pairs during the previous survey.
Graham Rees
Fieldwork 2003-07 (based on 490 tetrads)
Red = breeding confirmed = 131
Orange = breeding probable = 118
Yellow = breeding possible = 27
Total tetrads in which registered = 276 (56.3%)
Saturday, December 24, 2011 at 4:16PM Breeding resident
Both Mathew (1894) and Lockley et al. (1949) regarded the Mistle Thrush as a common resident. The Breeding Birds Survey of 1984-1988 found Mistle Thrushes to be more numerous south of the Cleddau Estuary and in north-east Pembrokeshire than elsewhere, where they were sparse. At an estimated ten pairs per tetrad in the main areas and two pairs per tetrad elsewhere, the population would probably be about 1,400 pairs.
They flock from July onwards, in groups varying from five to twenty birds, but over 100 were at Skomer on 3 October 1983 and an estimated 500 appeared on Ramsey on 12 October 1972. Flocks disappear before the winter and Mathew considered that they migrated south. He was probably right but we have found no direct evidence to confirm this.
The Mistle Thrush is generally sparsely distributed during the winter, some territories becoming deserted, while in others residents firmly defend well-berried trees.
Fieldwork 1984-88 (based on 478 tetrads)
Red = breeding confirmed = 89
Orange = breeding probable = 68
Yellow = breeding possible = 57
Total tetrads in which registered = 214 (44.8%)
Sunday, November 13, 2011 at 10:11AM 
Red = breeding confirmed
Orange = breeding probable
Yellow = breeding possible
Sunday, October 9, 2011 at 9:28AM 
The BTO winter atlas showed that Mistle Thrushes were present in the majority of 10km squares during the winters of 1981-82, 1982-82 and 1983-84.
The darker the colour, the higher the relative total count for each 10km square. The darkest blue represents over 15 birds seen in a day.
Graham Rees
Sunday, September 26, 2010 at 12:18PM Species account from M Mathew, 1894, "The Birds of Pembrokeshire and its islands"
