Black-tailed Godwit (Limosa limosa)
Black-tailed Godwit © Peter Twist
Black-tailed Godwits have increased greatly during the last century. To Coward (1910) they were only known in Cheshire as a rare visitor on migration. By the time of Bell’s 1962 avifauna, the species was a regular passage migrant in varying numbers and to some extent a winter visitor. Wintering birds had been reported since at least 1939 when one was at Bromborough Dock from 12 November to 12 December, followed by a flock of 15 at Hoylake on 10 January 1947 and records of wintering in five of the ten winters 1949/ 50 to 1958/ 59. The 1960s saw a large change in the species, with flocks at Burton Marsh up to 70 on 20 November 1960, with 40-50 still present two weeks later, there having been no previous evidence of any such numbers in the Dee. It was also a regular visitor to the south shore of the Mersey estuary, with a flock of 45 at Ince in mid-November 1961. Bell (1967) reported that between 60 and 70 birds wintered, with their favourite localities continuing to be the Dee estuary and the Mersey around Frodsham and Ince.
The Black-tailed Godwit’s preferred habitat is muddy estuaries, the areas with fine sediments rather than sand, in which they use their long bills to extract lugworms and ragworms, and by the late 1960s it was realised that hundreds of birds were feeding far offshore in the Dee, only being driven within view by the highest spring tides. The first BoEE counts found over 600 throughout winter 1970/ 71, with 1,471 in February 1973, although with great variation from month to month and year to year. The Dee figures were usually over 1,000 during the 1980s, and topped 2,000 on some counts in the 1990s. From the 2000/ 01 winter onwards, numbers exceeded 3,000 and rapidly surpassed the 4,000 mark. Very few were on the Mersey until 1984/ 85, when 150 were recorded, but totals remained at a relatively low level until shooting up from 1995, topping 1,000 in 1996 when 1,429 were counted on 24 November 1996, and 2,086 in January 1998. This was the first winter in which the Mersey WeBS figure was higher than that for the Dee, although often the majority of the Dee birds were in Wales, but no county recorder or bird report editor has tackled the presentation of true figures for Cheshire and Wirral.
After the species’ remarkable rise, nationally and locally, the Dee is second in the national ranking on current WeBS figures, with a five-year peak mean of 4,700 birds. The large numbers on the Mersey in autumn, around 2,500, reduce to an average of 500 over winter, just exceeding the threshold for international importance of 470. The main factor driving the increase seems to be a large rise in the Icelandic breeding population, possibly through climatic amelioration or changes in land use (Brown & Grice 2005).
During this Atlas, there were several instances of four-figure flocks within a single tetrad, headed by 2,250 in SJ27T and 1,500 in SJ27S, both on the edge of the Dee estuary saltmarsh. The other high counts were also in contiguous squares along the Dee shore, 750 off West Kirby (SJ28C), 800 of Thurstaston (SJ28G) and 580 off Heswall (SJ28K). The highest counts in the Mersey tetrads were 418 in SJ47D and 400 in SJ47I, both in Stanlow Bay. The freshwater sites adjacent to the estuaries are important for the species where they can supplement their diet with earthworms – Inner Marsh Farm (SJ37B) (which held a maximum of 700 birds in 2006/ 07) and Frodsham Marsh – and there is considerable interchange between the flocks at these two sites. There were few Atlas records of birds away from the estuaries and adjacent sites, with 50 on a flooded field alongside the River Weaver near Aston (SJ57N) in 2005/ 06 but elsewhere birds were only in single-figure groups.
The Black-tailed Godwits visiting the county are of the race islandica, breeding in Iceland and larger, but shorter-billed, than the nominate race that breeds in continental Europe. Sightings of colour-ringed birds have shown fascinating detail of their movements (Smith et al 2008).
Black-tailed Godwits were reported in the breeding season from 15 tetrads, some of them being in breeding plumage and some of the sites providing potentially suitable breeding habitat of wet meadows; but none of the birds was displaying or otherwise showing breeding intent and many of them were likely to be immatures, this species not breeding until at least two years of age. They have never bred in Cheshire and Wirral and Black-tailed Godwit is a rare breeder in Britain, with the Rare Breeding Birds Panel reporting that 63-75 pairs bred at 15 sites in 11 counties in 2004, the majority of these at the Ouse Washes in Cambridgeshire but including two sites in Lancashire (Holling et al 2007). Intriguingly, these, including the Lancashire birds, are all thought to be of the limosa race from continental Europe (Holling et al 2008).
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