Hill and colleagues have studied the wider impact that garden ponds might have on biodiversity. In one paper, published last year, the researchers counted the different species in a total of 50 garden and non-urban ponds in Oxfordshire. The rural ponds had a noticeably larger diversity of species, 172 to the garden ponds’ 99, but that doesn’t rule out their significance. It’s still a large enough selection of plants and animals to suggest that garden ponds could act as refuges or stepping stones for wildlife in urban landscapes, the authors wrote. Plus, the most diverse example of the garden ponds they studied punched above its weight and was comparable in terms of biodiversity to the non-urban ponds.
In separate research, published in 2016, Hill and colleagues assessed data from multiple earlier studies to quantify the number of invertebrate species – such as dragonfly nymphs – across 800 or so ponds in the UK, 230 of them in urban locations. They found that there was a similar variety of species and invertebrate families represented across different types of ponds, again highlighting garden ponds’ potential as wildlife havens.
“I would say they are under-used as a biodiversity resource,” says Hill.
The benefits of ponds may be broader, even, than that. As Pippa Johnson, ponds officer for Cheshire Wildlife Trust, notes, watching wildlife dart and dash around the surface of a pond can give endless enjoyment. She herself has childhood memories of observing frogspawn hatch in her family’s garden pond.
“They’re good for nature but they’re also good for us,” she says. And she agrees with Hill that having a variety of different elements in a pond will offer the greatest assistance to wildlife.
However, it’s not all about the pond itself – the rest of the garden habitat surrounding any body of water is also worth considering. The Wildlife Trusts suggests maintaining a patch of unmown grass near the pond for young amphibians and butterflies and perhaps a compost heap, which animals such as grass snakes may lay their eggs in. Also, animals might find it easier to get into the garden in the first place if the habitat is bordered by hedging rather than walls or a solid fence.
The truth is that no-one knows what wildlife they’ll get in their pond until they build it. And while maximizing nature’s chances by design is worthwhile, it’s also OK to experiment, says Steel.
“It is a subject that you can overthink,” she adds. “The water itself is the important part.” Next door to her garden, for instance, lies a pond in a field that has formed quite naturally after someone dug a hole in the ground many years ago. The pond gradually filled with rainwater and wildlife eventually took it over.
“It’s now an amazing pond – and nobody has done anything to it,” says Steel.
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