British Jay - 1949 status

Garulus glandarius rufitergum

Resident, but not numerous, in all well-wooded areas, and occasionally visits small woods in more exposed districts, eg in Oct 1947 it was seen at Dinas Island, St Ishmaels and St Davids.

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

Jay - 2003-07

The Jay is a medium-sized bird which is pinkish-brown in appearance, with blue and white wing patches, black tail and white rump. Despite its striking appearance, the Jay is shy and retiring and its presence is often first revealed by its raucous call. It is found in woodland and mature gardens, placing its nest close up to the trunks of trees or among thickets of ivy or thorns.

An estimate of 600 pairs breeding in Pembrokeshire was made at the close of the 1984-88 survey, based on an average density of three pairs per occupied tetrad. The 1988-91 National Atlas used an average density of four pairs per tetrad when calculating the UK total breeding population. The relative abundance map in that book indicates that this value might well have been applicable to Pembrokeshire. This would have elevated the county total to 800 pairs. The BBS charted a decrease of 14% across Wales between 1994 and 2007 and the survey of 2003-07 returned a 6% increase in distribution in the county. Applying the BBS value to the 2007 county distribution, results in an estimate of 730 pairs breeding in Pembrokeshire at the end of 2007.

Graham Rees

 

Fieldwork 2003-07 (based on 490 tetrads) 

Red = breeding confirmed = 31

Orange = breeding probable = 85

Yellow = breeding possible = 96

Total tetrads in which registered = 212 (43.3%)

Jay - 1994

Breeding resident

Resident according to Mathew (1894) and Lockley et al. (1949) but not numerous. Today Jays breed throughout the wooded areas of Pembrokeshire including the more mature conifer plantations. Experience of some woodland plots suggests that three pairs per tetrad would be a reasonable assessment of average density, and hence the total population would be about 600 pairs.

They are periodically eruptive, with small groups being found wandering around the open coast during the autumn. This could be triggered by high productivity or a response to food shortage. The acorn crop failed in 1983 and Jays were widely eruptive in both Britain and on the continent.  They had enjoyed a successful breeding season in West Wales that year, and the combination of these factors resulted in many flocks wandering westwards, largely in October and early November (John and Roskell 1985). In 1983, 200 birds passed south over Martin's Haven on 6 October and 127 coasted southwards at Strumble Head on 19 October.  Many smaller parties were seen moving along all the coasts and groups of up to 20 were frequently seen about the exposed coastal plains, where Jays are not normally found. Up to 38 reached Skomer and two were seen flying out to sea towards Ireland from Strumble Head — they were watched until lost to view, still heading steadily north-west.

   

Fieldwork 1984-88 (based on 478 tetrads) 

Red = breeding confirmed = 60

Orange = breeding probable = 32

Yellow = breeding possible = 108

Total tetrads in which registered = 200 (41.8%)

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

Jay - 2006

Jay Garrulus glandarius

Breeding resident.

 Jays are found across the middle latitudes of the Western Palearctic.  

The Jay was considered to be resident in Pembrokeshire but not numerous by both Mathew (1894) and Lockley et al (1949). Gamekeepers in the county were known to have kept numbers down right up to the beginning of World War II, B. Lloyd (1939) for instance noting 28 strung up on a gibbet at Slebech in 1927. Jays currently breed in woodland and mature gardens throughout the county and are largely unmolested.

Breeding distribution 1984-88

Breeding distribution 2003-07

Pembrokeshire Breeding Birds Surveys.

Breeding surveys	1984 – 88	2003 – 07
Total tetrads where found	200	212
Confirmed breeding	60	31
Probable breeding	32	85
Possible breeding	108	96

An estimate of 600 pairs breeding in Pembrokeshire was made at the close of the survey of 1984 -88, based on an average density of three pairs per occupied tetrad. The New Atlas of 1988 – 91 used an average density of four pairs per tetrad when calculating the UK total breeding population. The relative abundance map they produced indicates that this value might well have been applicable to Pembrokeshire. This would have elevated the county total to 800 pairs. The BBS charted a decrease of 14 % across Wales between 1994 and 2007 and the local survey of 2003 – 07 returned a 6 % increase in distribution in the county. Applying the BBS value to the 2007 county distribution, results in an estimate of 730 pairs breeding in Pembrokeshire at the end of 2007.

Normally sedentary, in some years there have been eruptions into areas outside typical woodland habitat, including coastal localities and the islands of Ramsey and Skomer. These have coincided with years of high breeding productivity and/or poor acorn crops. Such events were noted in 1947, 1961, 1966, 1972, 1983, 1993, 1996, 2001 and 2005 and were probably regional in origin, with the exception of 1983 when a 90% failure in the acorn crop across northern Europe, including the UK, caused a major eruption of Jays. Large flocks were seen moving westwards over southern Britain during October which probably included continental birds. Groups of up to 25 were widespread in coastal Pembrokeshire, many of which remained over the winter. Notable movements were 200 passing over Martin’s Haven on the 6th October, 32 reaching Skomer that day, and 127 passing along the coast at Strumble Head on the 19th October, where two were watched out of sight flying over the sea towards Ireland.

Graham Rees.

(Covers records up to and including 2006).       

Jay - 1970s breeding

Red = breeding confirmed

Orange = breeding probable

Yellow = breeding possible

Jay - 1980s winter atlas

The BTO winter atlas showed that Jays were present in most 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 11 birds.

It is possible that the highest numerical plots were due to a hangover from the Jay invasion of autumn 1983. 

Graham Rees

Jay - 1894

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

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