Pond survey
The Plumpton parish pond survey, the first of its kind in Sussex, was conducted in 2009. A total of 93 ponds were surveyed across the parish.
We used the following nationally accepted definition of a pond: a natural or man-made water body between one metre squared and two hectares in area that holds water for four months of the year or more. Nationally, about two thirds of all Britain’s freshwater plants and animals can be found in permanent and temporary ponds. Ponds are fast becoming the last refuge for some species like the White-clawed Crayfish, which has been almost completely lost from many rivers as a result of crayfish plague carried by introduced American Signal Crayfish. Many ponds in Plumpton and the wider lowlands have a historical significance, their origins reflecting the needs of the day. We have old mill ponds, brick pits, duck ponds, livestock watering ponds, farm ponds and even a moat. The modern ponds in the Parish reflect today’s needs: they are mostly ornamental fish ponds and sustainable urban drainage ponds around our larger housing developments. Though this parish still has a good number of ponds, very few support a high diversity of aquatic life. Only four per cent are species-rich. This reflects the national picture – around 80% of ponds in England are in a poor or very poor condition. Even in the last 10 years pond water quality has been declining, linked to increases in nutrient pollution from the arable switch in the lowlands and increases in road traffic run-off, compounded by greater use of diesel cars. The best ponds are not connected to streams or ditches and have a clean catchment. In Plumpton 55% of ponds are connected to streams and ditches. The best ponds for wildlife don’t contain fish. Naturally, ponds away from river floodplains would be fish free. Half of our aquatic plant and animal species are not tolerant of fish, even native ones, at natural stocking densities. In Plumpton 33 ponds (of the 58 that hold water through an average year) support fish. Most of these contain carp species at very high densities, with no evidence of invertebrate life at all. For example, the pond next to the village hall contained only nine species and 11 individual invertebrates after three minutes of netting. By contrast, the ditch overflow below the pond, which has no fish, contained 17 species and 83 individual invertebrates after 30 seconds of netting. The good news is that very few ponds contained alien invasive species of plants. Only two contained Crassula helmsii (Australian Swamp Stonecrop) and three contained Myriophyllum aquaticum (Parrot’s feather) – and all these ponds had been planted up. The survey also found four new Great Crested Newt (Triturus cristatus) records for the parish, one new toad breeding pond and several new breeding records for common frog (Rana temporaria) and smooth newt (Lissotriton vulgaris). The survey also found two eels (Anguilla anguilla) in one pond. We are happy to offer advice on maximising the wildlife value of your pond. Just get in touch! |
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