Beddington Farmlands Bird Group
SLUDGE LAGOONS AND BEDS
Out of the devastation came a new beginning. As part of the continuing theme of Beddington, inadvertent side effects of commercial operations actually turned out to be beneficial to bird life. The sludge beds, which had replaced and destroyed the old wet meadows, over time, matured into wetland habitat themselves.
About 130 beds covered just over a half of the farm and of these beds, about 100 were flooded at some time during the year with sludge. The remaining 30 were disused and overgrown with vegetation. The fields covered about one third of the farm, mainly on the western side, and were occasionally ploughed and flooded in winter. In 1978, five very much larger sludge dewatering beds just to the north of Mile Road were completed. The large volumes of these beds resulted in a lessening in the frequency of flooding of the remainder of the beds (Hatton, 1982).
Each sludge drying bed passed through a cycle, which started when one of the final products of the sewage treatment process is pumped into the bed. At this stage, it contained little invertebrate life, but was quickly colonised such that it becomes full of invertebrate life. Vegetation began to colonise the drier areas of sludge while pools of water often developed. As ageing continued, the bed continued to dry out and became increasingly dominated by ruderal vegetation. Ruderal vegetation was noted for its high seed production, which is an important source of food for seed-eating birds. In the early stages of the cycle, beds were very attractive to wetland species while towards the end of the cycle they attracted seed-eating species. The larger dewatering bed were always wet and so were particularly important at passage times for migrant waders.
It was not all good news. The pumping of sludge onto the smaller beds was often a source of frustration amongst the regular birdwatchers. Fresh sludge was sometimes pumped out during the middle of the breeding season severely impacting on breeding activity.
In 1978 Gary Messenbird joined Roy Weller and Derek Coleman in birding this emerging wetland habitat and within a few years had unravelled an understanding of this maturing environment. Migrant waders became synonymous with Beddington and in 1984 this was immortalised when Gary discovered a Killdeer in January and a few months later found a juvenile Lesser Yellowlegs.
Soon more birders started to visit. Firstly David Hatton, Nick Gardener, Steve Gale and Simon Aspinall and by the late 1980’s John Walsh, Roy Weller, Nick Moore, Andrew Pearson and Peter Alfrey had joined in recording the unfolding events and began to detail trends in migration, breeding and wintering.
The beds were reminiscent of the old Beddington meadows and held breeding populations of Lapwings, Yellow Wagtails, Skylarks and Reed Bunting and in the winter the wet fields were host to flocks of Snipe and Lapwing. The flocks of Snipe did not compare to the 5000+ recorded in 1962 but flocks of 210 in 1979 and between 75 and 100 in 1986 to 1990 were regionally significant. Redshank after many years absence as a breeding bird, recolonised the site.
The Short-eared Owls that were wintering in small numbers in the early 1980’s became scarce from 1987, probably related to the 200 or so horses which grazed the fields and beds, cropping the grass rendering it unsuitable for supporting large populations of small mammal life. The practise of cutting the sides of the large digester sides was also detrimental for this species. However the horses and vegetation management was perhaps beneficial to the breeding Yellow Wagtails and kept the grass short for migrating Wheatears, which could be expected most springs in small flocks frequenting ploughed beds and open grass fields. Black Redstart and Ring Ouzel could be expected on migration and Whinchat was well represented on passage.
It was the autumn wader migration that Beddington became most associated with. Spotted Redshank, Greenshank, Redshank, Green Sandpiper, Common Sandpiper, Wood Sandpiper, Little Stint and Ruff were annual migrants in relatively reasonable numbers, frequenting the wetland beds and enclosed lagoons (the digesters).
In 1984, excavation started on an even larger sludge dewatering bed. This bed was not used and allowed to fill with water while the banks were colonised by vegetation. This open water body attracted good numbers of wetland birds. Gadwall, Shoveler and Pochard that were a sought after species were now regular. In September 1987, the lagoon was drained and further excavations were carried out and it attracted Little Ringed and Ringed Plover the following summer before it was filled with sludge.
The year of 1987 will be remembered for the Great Storm of October 16th which in the aftermath added Grey Phalarope and Sabine’s Gull on the Beddington list.