Adult Buzzards in Britain are highly sedentary and territorial, rarely moving out of their breeding territory once established. In contrast, some continental populations migrate well south for the winter. Thus the distribution of buzzards in Pembrokeshire in winter is pretty much the same as in the breeding season.
Young Buzzards, dispersing from natal sites, tend to wander the countryside in search of food and their own territories. They often gather in autumn and winter wherever invertebrate and carrion food is plentiful. Groups of 20-30 birds in stubble or ploughed fields are not uncommon.
Impressive movements of these nomadic immature birds are occasionally noted, for example, 58 flying west over Treginnis, near St Davids, on 5 October 2005.
Ringing studies in the BTO Migration Atlas suggest that most first winter birds typically stay within 20km of their natal sites, but some do go further in their initial explorations. An extreme example is a female nestling ringed near Lampeter (Ceredigion) in June 1977, and found in Northumberland in May 1990, while a bird tagged in Dumfries, Scotland, in 1994 turned up in Caernarfonshire a year later. As most ringing recoveries are of dead birds, it may be worth checking any road casualties and other corpses for rings to further this knowledge locally.
The BTO Atlas 2007-11 shows no change in winter distribution across Pembrokeshire (or most of Wales) and their relative abundance here is similar to that across the rest of Wales (though it is lower in the mountains)and south-west England.
Annie Haycock (BBS & WeBS local organiser)
BALMER D, GILLINGS S, CAFFREY B, SWANN B, DOWNIE I, FULLER R. 2014. Bird Atlas 2007-11: The Breeding and Wintering Birds of Britain and Ireland. HarperCollins. UK
The distribution of Buzzards recorded during the two atlas survey periods is almost identical and the number of registrations 398 (405) is also very similar. Estimating the number of breeding pairs of Buzzards is fraught with problems. Many of the birds which are seen displaying and even lining a nest are non-breeding birds and studies indicate that only 25% of the population actually breed. Also a pair may frequently line more than one nest.
In their prime habitat of fairly well-wooded undulating countryside they can reach densities of up to 0.88 pairs per km2 (Sim et al 2001). Much of the east of the county can be considered to be perfect habitat, but in the more open and exposed west, breeding density is likely to be lower. If an average density is assumed of two to three pairs per tetrad over 250 tetrads in the east and one pair per tetrad over 150 in the West, then a population range of 650 to 900 pairs breed within the county, a considerable increase from the 1984-88 estimate of 250. Increases of this order have been recorded at a UK level but the Welsh population has remained stable since 1994 (BTO website).
Given that the range has remained unchanged between the two survey periods then at least some of this increase may be explained by variation in the methods used to make the estimate.
Only half a dozen pairs were known to Mathew (1894) but Lockley et al. (1949) estimated “probably not less than 120 pairs” were breeding, an increase that occurred throughout the Buzzard’s range in the post 1914-1918 War period (Moore 1957). They have continued to increase since and in 1954 Skomer, with seven or eight pairs on 722 acres, had the greatest numbers of Buzzards per square mile recorded in Britain (Moore 1957). It is estimated that 250 pairs were breeding in the county during the Breeding Birds Survey of 1984-1988.
In Pembrokeshire, Buzzards nest mainly in trees; in the most open terrain nests can be as little as 1.5 metres from the ground in low hawthorns. Cliff ledges are used around the outer coast and on the larger islands. The breeding distribution is broadly uniform across the county but there are concentrations in heavily wooded valleys such as the Gwaun and Treffgame.
The reduction in rabbit numbers caused by the introduction of myxomatosis from 1952 to 1954 initially caused widespread breeding failure among Buzzards. For example, they almost disappeared from the south-west peninsula in 1955 when along 30 km of coastline on the St David’s peninsula, including Ramsey, there were no successful nests. The Skomer population declined to two pairs but quickly recovered to four or five pairs (Davis and Saunders 1965) and has remained largely at that level subsequently. Clutch size has also reduced with one, occasionally two, eggs now being normal whereas three was not uncommon formerly.
Probably not less than 120 pairs breeding in the county, on the coast, islands, and inland. In Mathew’s day there were believed to be only half a dozen pairs, of which one pair was found by Howard Saunders on the north side of Dinas Head.
There are so many Boncaths in the county, either hamlets or inns, that we have in this fact a sure witness to the former abundance of the Common Buzzard in Pembrokeshire, “Boncath” being the Welsh name of the bird. At the present day we are only able to state that there are a few Buzzards left in the county, and that there may be possibly still some half dozen nesting stations of the bird on the islands, and on the cliffs along the coast.
We have seen the Buzzard at Stone Hall, and have several times spared it when we have been Woodcock shooting in warm bottoms not far from the sea. The bird has flown foolishly up to us, or has crossed low over head, presenting an easy shot. We have seen a Buzzard’s nest on a cliff on Ramsey Island, and possess an egg from it, one of a clutch taken by Mr. Mortimer Propert. All the Pembrokeshire Buzzards’ eggs that we have seen are large in size, the one we have is larger than any in a long series of continental eggs in our cabinet, but, as the Rev. C. M. Phelps remarks, “they are not as a rule richly marked.” The Rev. C. M. Phelps agrees with us in estimating the present breeding stations of the Buzzard to be about six, and he adds that they are all on high cliffs.
Mr. Dix writes: “In May, 1866, I had the unexpected pleasure of seeing a pair of Buzzards at Llangranog, on the Cardiganshire coast, where I have no doubt they had a nest. I was first struck by their peculiar, plaintive note, greatly resembling the mewing of a kitten. Never having seen this bird on the wing before, and they being some 300 ft. above me, I was some time before I could be sure of the species. They were mobbed by several Crows and Jackdaws; as they wheeled and doubled about their rounded wings gave them a very unhawk-like appearance. I was glad to find they had selected so safe a nesting place, it being a shelving rock overgrown with ferns and grass.”
Buteo buteo – BWNCATH – Breeding resident Adult Buzzards in Britain are highly sedentary and territorial, rarely moving out of their breeding territory once established. In contrast, some continental populations migrate well south for the winter. Thus the distribution of buzzards in Pembrokeshire in winter is pretty much the same as in the breeding season. […]
Buteo buteo – BWNCATH – Breeding resident Comparison with previous atlas: 1984-88 2003-07 Breeding confirmed 156 124 Breeding probable 79 167 Breeding possible 170 107 No of tetrads occupied 405 (of 478) 398 (of 490) Percentage of tetrads 84.7% 81.2% The distribution of Buzzards recorded during the two atlas survey periods is almost identical and […]
Buteo buteo – BWNCATH – Breeding resident 1984-88 Breeding confirmed 156 Breeding probable 79 Breeding possible 170 No of tetrads occupied 405 (of 478) Percentage of tetrads 84.7% Only half a dozen pairs were known to Mathew (1894) but Lockley et al. (1949) estimated “probably not less than 120 pairs” were breeding, an increase that occurred throughout […]
Buteo buteo – BWNCATH – Breeding resident The BTO winter atlas showed that Buzzards were present in most 10km squares during the winters of 1981-82, 1982-82 and 1983-84. The darkest blue represents over 7 birds recorded in a day, the next lightest 3-6 birds, suggesting fairly even distribution. More about the Buzzard in Pembrokeshire
Buteo vulgaris – BWNCATH There are so many Boncaths in the county, either hamlets or inns, that we have in this fact a sure witness to the former abundance of the Common Buzzard in Pembrokeshire, “Boncath” being the Welsh name of the bird. At the present day we are only able to state that there are a few Buzzards left […]