Garden pond numbers and conservation importance
By Ian Thornhill and Steve Head.
Number of garden ponds
There are good estimates for the number of ponds in the British countryside: in 2007, the number was last estimated at 478,000 (Countryside Survey Technical Report No. 7/07
.) with losses in the last 100 years estimated at somewhere between 500,000 and 1 million, but with a small net gain in recent years.
However, the Countryside Survey specifically excluded urban areas. The best estimate available for the number of garden ponds is the BUGS project which estimated that there are over 25,000 ponds in Sheffield's 175,000 households, or 14%. Extrapolating this up for the UK, where there were 26.4 million households in 2013, gives an estimate in the order of 3.8 million ponds.
However, most garden ponds are likely to be tiny compared with those in the countryside, so their total area and volume compared to the overall total pond resource in the UK is likely to be small. See our leaflet Ponds in gardens and the countryside
for more information
Conservation value of ponds
The National Amphibian Survey (Swan & Oldham 1993
) concluded that "There are no grounds for assuming that [garden ponds] contribute significantly to the conservation of amphibians nationally." Thirty six years later, with a further decline in countryside biodivversity, this is no longer true. Garden ponds are now very significant for frogs
and and many populations in suburban
areas depend on them. In his paper for the Forum's November 2009 Conference
, Dr Jeremy Biggs of Pond Conservation (now the Freshwater Habitats Trust
) considered that garden ponds are of importance for frogs and possibly smooth newts and the cleanest ones supported more dragonfly species than the Great Britain average for countryside ponds.
More recently Matthew Hill and Paul Wood (2014)
studied field and garden ponds around Loughborough, and found garden ponds mostly had a very reduced diversity compared with the field ponds, in part attributed to isolation and presence of fish. However, garden ponds often contained pumps and fountains, allowing some flowing-water (lotic) creatures to live as well as the more typical still water (lentic) specialists. The authors concluded that garden ponds could be a significant reserve for some species, especially dragonflies and damselflies. However, they felt most garden ponds they studied were kept by gardeners for appearance rather than wildlife benefit, and so there is considerable room for improvement in management.
We do need more data on garden pond biodiversity!
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