Search
Close this search box.

Small Ponds, Teeming With Life

Small Ponds, Teeming With Life

Over the last few years we’ve been improving our existing ponds and, where possible, creating a few more. Here is why.

Ponds and scrapes (shallow, more temporary water bodies) are incredibly important hotspots for biodiversity. Collectively, ponds support more species, and more scarce species, than any other freshwater habitat. They are also one of the most abundant freshwater habitats in the UK and are found in nearly all environments. A network of wildlife ponds across an urban landscape provides a much-needed refuge for birds, mammals, amphibians, reptiles, and flying insects, writes our Conservation Manager, Will Dartnell.

However, the rate of pond loss across the UK has been substantial. At the start of the 20th century, there were an estimated 800,000 ponds in Great Britain, which declined to 200,000 by the 1980s. Thankfully, pond creation and management has increased since then, and there are now an estimated 478,000 ponds in England, Wales, and Scotland, but there is still some way to go before we have a well-connected network of ponds at the landscape scale.

Small pond behind the black poplar nursery

Ponds are incredibly important for aquatic plants and invertebrates; annual surveys show that one of our ponds has close to 20 different species of aquatic invertebrate and given the short survey time there are likely to be many more that we are yet to find and record. The benefits of ponds can also extend to terrestrial wildlife through numerous aquatic-terrestrial ecological interactions. Adult flying life stages of aquatic invertebrates, often emerging simultaneously in vast numbers, can provide an important food source for many nesting and fledging bird species as well as rich hunting ground for bats. Furthermore, ponds provide drinking water during dry weather and shelter among the emergent and surrounding plants and trees. This is especially important in the urban environment which may otherwise be lacking in places for wildlife.

One of the most important parts of the pond habitat is the ‘drawdown zone’. This is the area, which is subject to seasonal fluctuations in water depth, being wetter in winter and drying out in summer, and it is an exceptionally rich wildlife habitat. It is important for marginal plant species that need some exposure to air for plant seeds to germinate as well as some species of dragonfly, such as the southern hawker, laying their eggs in the damp, exposed drawdown zone. So please don’t be concerned when you see water levels dropping.

Damselflies in summer

However, ponds require management as through succession they will eventually develop into seasonally flooded wet woodland habitats, with the ponds filling in with silt. Therefore, in order to maintain a pond habitat, it is important, on a rotational basis, to make sure that light levels are sufficient enough to reach the water. Research has shown that these open canopy ponds result in higher levels of aquatic plants and insects. This has been seen on the pond restoration work on the Common, whereby surveys prior to restoration work showed a maximum of five species of macroinvertebrates and after increasing light levels, through tree work, and desilting the pond, within 1 year surveys showed 15 species of macroinvertebrates and the establishment of new aquatic plants.

As many of you have seen, with the help of lots of volunteers, we are in the process of building a few small new ponds on the edge of the old cricket field (by Vine Road). These ponds are nearly complete, but we do hope to add one more in early spring along with a raised walkway constructed from milled timber from the Common, that will run alongside the new ponds. The ponds will be left to develop at their own pace with survey work carried out on an annual basis.

However, as with all our ponds and wetland areas, we do need to make sure that they are protected. We will be adding a dead hedge around the area, as repeated disturbance caused by dogs can lead to dramatic changes in the water quality and structure of vegetation, and ultimately result in the loss of wildlife. Furthermore, it’s important not to let your dog into any body of water after using flea treatment. A study from the University of Sussex found fipronil, a chemical mostly widely used in pet flea treatment, in 99% of nearly 400,000 water samples taken from 20 UK rivers. Imidacloprid, another pesticide found in pet flea treatment, was found in 66% of samples. Fipronil and imidacloprid are potent nerve agents that are highly toxic to insects. For instance, it is estimated that one flea treatment of a medium-sized dog with imidacloprid contains enough pesticide to kill 60 million bees! So please, do help us to protect our local wildlife.

For more info on any of our conservation work, contact Will at [email protected]