The Story of Breeding Waders on the Somerset Levels
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Farewell to the silver meadows? The story of breeding waders on the Somerset Levels Flooded meadow at West Sedgemoor RSPB reserve. Richard Archer Chris Gomersall/rspb-images.com mong the pleasures of early spring the fen meadows and flood pastures of 11 grassland sights and sounds of the Somerset Levels Sites of Special Scientific Interest (SSSIs) in the Aon a still morning are hard to beat. Court- heart of the Levels, and to a few non-designated ing Snipe chip and drum above the damp hay satellite sites (Fig. 1). The Levels today are one of meadows on West Sedgemoor, and Greylake’s the four most important areas for breeding waders splashy pastures resound to the urgent ‘leeu leeu’ in lowland England, despite a long and continuing calls of displaying Redshank. history of wetland decline. This article gives an overview of breeding February and March can be a noisy time on the waders on the Somerset Levels over the past Levels as returning waders display and establish century. ‘The Levels’, as the area is known locally, territories. Curlews Numenius arquata are usually consists of 30,000ha of peat and clay moors in the first to arrive, appearing from early February the floodplains of the Brue and Parrett rivers, and in older hay meadows and unimproved pasture. includes the Somerset Levels & Moors Special Unlike other Levels’ waders, Curlews are less Protection Area and Ramsar site, designated for closely tied to high water levels and adult birds its non-breeding waterbirds and rare aquatic will range quite widely to feed. They do well on invertebrates. The key breeding-wader moors – West Sedgemoor, where there are extensive, tradi- Somerset’s ‘silver meadows’ – are confined to the tionally managed swards, and on the northern December 2013 British Wildlife 77 252somersetlevels.indd 77 04/12/2013 13:30 Farewell to the silver meadows? The story of breeding waders on the Somerset Levels Farewell to the silver meadows? The story of breeding waders on the Somerset Levels Key: 1 Chilton, Edington, Catcott & Burtle Moors; 2 Tealham & Tadham Moors; 3 East & West Wastes; 4 Queen’s Sedgemoor & Crannel Moor; 5 Greylake & Moorlinch; 6 Butleigh, Walton & Somerton Moors; 7 King’s Sedgemoor; 8 Aller Moor; 9 Southlake Moor; 10 North Moor; 11 Curry & Hay Moors; 12 West Sedgemoor; 13 Muchelney Level & Hay Moor; 14 Wet Moor; 15 King’s Moor & Whitcombe Bottom; 16 West Moor. Figure 1 The key moors for breeding waders in the Somerset Levels. part of Wet Moor. ping and drumming’ in mid-March. Snipe nest Lapwings Vanellus vanellus appear in late in taller, more tussocky vegetation than Lapwing February and early March, when it can be diffi- and Redshank, and favour peaty fields with water cult to separate breeders from departing winter- tables to within c. 20cm of field level through- ing birds. They like unimproved fields with short out the breeding season. Seasonally flooded hay swards, although up to a third of the pairs take meadows on West Sedgemoor hold the highest advantage of spring-sown maize, harvested withy densities of breeding Snipe on the Levels. Tealham beds and old peat workings. Lapwings need & Tadham Moors and Wet Moor have also held splashy pools and ditch edges for feeding from good numbers of breeding Snipe in the recent past. early spring into early June. Monitoring on Grey- Traditional wet pasture and hay meadows lake suggests that nests are particularly vulner- provide good habitat for breeding waders on the able to ground predators, especially Foxes Vulpes Levels. Moderate soil nutrient levels and low- vulpes. Butleigh, Walton and Somerton Moors intensity management encourage high inverte- have traditionally held good numbers of breeding brate diversity and an open sward, allowing easy Lapwings, as have West Sedgemoor, Tealham & passage of wader chicks, while providing good Tadham Moors and West Moor. nesting cover. Drainage is often impeded, and high Redshanks Tringa totanus usually appear in soil water levels encourage surface splash, allow- March, often accompanied by passage birds. They ing Lapwing and Redshank to take aquatic inver- favour unimproved tussocky pasture for nesting, tebrates from the water surface, exposed mud and and, as with Lapwings, need splash conditions vegetation. Soft, damp soils also allow Snipe and from early spring for foraging. Greylake RSPB Curlew access to worms and other invertebrates. reserve is the most important site for Redshank, Traditional Levels farming involves a late start to along with West Sedgemoor. King’s Sedgemoor summer grazing, usually from mid- to late May, and Tealham & Tadham Moors have traditionally and hay is mown from early July. This signifi- held good numbers as well. cantly reduces the losses of wader eggs and chicks Male Snipe Gallinago gallinago begin ‘chip- to cattle trampling and mowing. 78 British Wildlife December 2013 December 2013 British Wildlife 79 252somersetlevels.indd 78 04/12/2013 13:30 Farewell to the silver meadows? The story of breeding waders on the Somerset Levels Farewell to the silver meadows? The story of breeding waders on the Somerset Levels The historical status of breeding waders There is little information about breeding waders on the Levels before 1900. The county’s first avifauna (Smith 1869) tells us little, although both Snipe and Lapwing were thought to be relatively common (Ballance 2006). Curlews probably appeared on the Levels from about 1900, although it is difficult to be certain because they were not a popular quarry species. The first evidence of breeding came from Queen’s Juvenile (left) and adult Redshank in July at Greylake RSPB reserve. Sedgemoor in 1900. Redshanks John Crispin also colonised the Levels at this time, first breeding on the Somerset coast at Steart benefited many wetland species, it did not meet Island in about 1900. By the 1930s, they had the needs of post-war Britain. There followed spread to the Brue Valley and King’s Sedgemoor, major improvements in land drainage, aimed at breeding on West Sedgemoor in 1927 and reach- extending the grazing season through the reduc- ing other parts of the central and southern Levels tion of damaging late-winter, spring and summer by 1940 (Palmer & Ballance 1968). floods. By the 1920s, Curlews had moved further onto Diesel pumps were installed on important the Levels. Birds are thought to have come from breeding-wader moors, including West Sedge- Exmoor, where traditional breeding sites were moor, which had previously drained only through lost to the plough in the 1920s and 1930s. Some gravity. Land drainage was further improved time before 1939, Curlews colonised West Sedge- through under-drainage of fields, allowing surface moor, and then spread onto King’s Sedgemoor water to drain to the new pumps through larger, and the moors south of Langport. In the 1930s, more efficient ditches and drains. Conveyance of Lapwing was abundant on the Levels and Snipe main rivers was improved to reduce river flood- bred widely in the Brue Valley and on the Parrett ing onto the moors, and also to cope with the moors, especially on West Sedgemoor (Ballance additional water pumped from the moors into the 2006). Breeding birds were at significant risk of rivers. From the 1960s, many of the diesel pumps spring and summer flooding, occasionally suffer- were superseded by more efficient, automated ing poor breeding seasons, as in 1936 and 1937. electric pumps. Nonetheless, the best years for breeding waders on These changes had an immediate effect on the Levels were probably in the 1920s and 1930s, farming, removing excess surface water from when traditionally managed wet grassland was fields, lowering water tables earlier in the year, widespread, and a lack of agricultural investment and extending the farming season into the spring. left many areas poorly drained. We can only spec- The North Drain pumping station, installed in ulate on the breeding population at this time, but 1959, could drain surface water from Tealham & there must have been significantly more than 800 Tadham Moors ‘within hours’ (Williams 1970). pairs of waders. Such control allowed rapid intensification of The 50 years from 1939 saw serious declines grassland management: species-rich hay meadows in the fortunes of wildlife on the Levels, including and traditional pasture gave way to intensive dairy breeding waders. Flooding had always restricted and beef swards and silage; grazing and mowing the summer growing season, limiting the produc- dates moved forward as soils dried earlier; and tivity of floodplain farming. While this may have carrots and potatoes were planted on the previ- 78 British Wildlife December 2013 December 2013 British Wildlife 79 252somersetlevels.indd 79 04/12/2013 13:30 Farewell to the silver meadows? The story of breeding waders on the Somerset Levels Farewell to the silver meadows? The story of breeding waders on the Somerset Levels ously waterlogged peat soils of West Sedgemoor Levels survey. Round showed that most breeding and other key wader moors. waders occurred on the dampest wet grassland The impacts of this activity on wetland ecology soils on 16 key moors, including the main site at took longer to recognise. There was limited under- West Sedgemoor, which supported about 141 standing of the ecological importance of the Levels pairs. Pump drainage was clearly having a devas- until the 1970s, and species and habitat data from tating impact, as Stan Davies had suspected. For the early decades of drainage between 1940 and example, Witcombe Bottom, which held 19 or 1960 were very limited. more pairs of breeding waders in 1972, held only There is evidence that Redshank and Curlew eight pairs in 1977, three years after the Long populations remained relatively healthy into the Load Pumping Station started operating. Simi- 1960s. Redshanks continued to spread until about larly, on West Sedgemoor, where a third of fields 1960 and were still present on ‘all suitable Levels’ remained moist into May, there were eight times in 1968 (Palmer & Ballance 1968).