Published on May 13th, 2014 | by Doug
Ponds – A Diminishing Habitat
Ponds are defined as man-made or natural bodies of water between 1m² and 2ha² which hold water for four months of the year. The definition is, perhaps, rather surprising for it is so broad. However, even the smallest pond can have a high wildlife conservation value and, even something that is present for less than half a year, can support both specialized and valuable pond communities.
It is easy to see how many ponds can be undervalued when the definition includes areas as small or as ephemeral as those defined above. It is perhaps also easy to think that, with this definition, ponds are abundant yet some three-quarters of Britain’s pond’s i.e. more than a million, have been lost over the last one hundred years.
Here at the Global Retreat Centre, we are making our contribution towards sustaining and enhancing biodiversity, in collaboration with the Million Ponds Project. The Chinese pond, designed by William Robinson at the turn of the last century, is fed from a small ditch collecting run- off from adjacent agricultural land.
In the last decade, the level of silt building up in the pond has meant that about one third of the surface area is now at or above the water level. While this in itself is beneficial to various species of plant and animal life, it does threaten the integrity of the pond over a long period of time. We believe the time has come to build a number of weirs into the ditch so encouraging sediment to be deposited prior to entry into the larger body of water. The existing sediment will be reduced.
However, Robinson’s pond holds a ‘secret’ that is only apparent in winter when the leaves have fallen and the perennial plants died back. Just below the outfall are a series of five concrete dishes gently descending the slope, each about 5m².
The last dish drains into an area that, while permanently wet, is really a seasonal pond. Nevertheless, the environment is ideally suited to terrestrial and aquatic wildlife – undisturbed, sun and shade, open water and sediment, without fish or too many wild fowl which increase the nitrogen levels leading to algal bloom. Plant diversity is also seen – Spring Snowflake, Kingcup and Yellowflag to name but a few.
Just to sit quietly in this oasis will bring you the pleasure of seeing, (or perhaps hearing) butterflies, dragonflies, an abundance of insect life, whitethroats, warblers, kingfisher, grass snakes, and muntjac deer. With a little knowledge and timing you can also see Great Crested Newts.
Hidden in the woods and screened by some of Robinson’s currently less valued plantings – Chinese Knotweed – who wouldn’t want to ensure this 0.5ha ecologist’s heaven isn’t sustained in its most valued state.