Botanists restoring ancient wetlands in England have made an unlikely discovery – ‘zombie’ pond life that comes back from the dead
They may sound like the murky, mist-wreathed setting for B-movie chills, but Norfolk’s ‘ghost ponds’ are enjoying a startling renaissance – and bringing centuries-old plantlife back from the dead.
The Norfolk Ponds Project was born a decade ago out of work by University College London’s Pond Restoration Research Group. Studying 200-year-old maps to locate ancient watering holes, researchers found thousands of ponds that had been filled and ploughed over in favour of farmland.
But what happened as they began restoring them took even the research team by surprise. “The seeds of water plants were still alive underneath the earth – even though it had been ploughed, furrowed, fertilised and used to grow crops,” said UCL professor of geography Carl Sayer.
“The term ‘ghost ponds’ is very apt. They leave behind a trace of their presence, and after centuries of burial – with a little help – they come back from the dead. If you can bring back the plants, everything else follows.”
Professor Sayer explained that the decline of wetlands in Norfolk, which is still home to more ponds than any other UK county, began in the 1800s and hastened in the post-second world war drive to ‘feed the nation’, when ponds on estates and agricultural land were buried to grow crops.
“Often, all that remains is a crop mark or a slight depression in the ground, a low in the field where mist collects, which gives it a very ethereal feeling,” he said.
Restoration is just a matter of digging out the profile of the original watering hole, taking care not to disturb the earth below ancient pond sediment, which contains the precious seed bank.
“The best thing you can do then is walk away and leave it,” said Prof Sayer. “The pond will fill up itself from rain and groundwater. We’ve dug out ponds in September and found that by next spring, plants are starting to grow. They feel the light and warmth on them for the first time in centuries and think: ‘right, here we go!’”
Prof Sayer jokingly referred to these reanimated pond-life relics as ‘zombie plants’, but the project has chalked up some remarkable results as it slops and digs its way into the past. “We’ve had really rare species come back, plants that have been extinct regionally and are extremely scarce in the UK as a whole,” he said.
He cited the example of rare grass-poly, found on the fringes of an old cattle-watering pond on the Heydon estate in Norfolk, after restorers disturbed wet soil by removing willows. The species had not been seen in the county for more than 100 years.
We’ve had really rare species come back, plants that have been extinct regionally and are extremely scarce in the UK
Despite their success so far, Prof Sayer and his team have some back-breaking toil ahead. In Norfolk alone, they have pinpointed some 8,000 ghost ponds in need of awakening. To date, they have revived or restored around 250.
But his zeal is contagious, and has sparked similar restoration projects in Lancashire, Cheshire, Suffolk and Herefordshire. “We’ve been busy restoring hedges and meadows, and growing bird food crops, and these ponds are sitting there being completely forgotten about,” Prof Sayer said.
“People are starting to realise that these tiny lenses of water out in the fields are actually really important. By reviving them, you lift the whole landscape.”
Main image: Ian Dinmore