This rare 460 million year old plant only found in one place in the UK has been discovered at RSPB Saltholme


Critically endangered 'bearded stonewort', a species of plant that dates back 460 million years, has been found in newly created ponds at RSPB Saltholme nature reserve, on the outskirts of Hartlepool.
Stoneworts are complex algae and are believed to be related to the ancestors of all land plants. Bearded stonewort is found in only one other known location in England, the Peterborough brick pits.
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Hide AdBearded stonewort is a pioneer species, which means it is one of the first plants to grow in disturbed soil. The dragonfly pools at RSPB Saltholme were dug in 2019 and this work will have disturbed spores that may have been dormant in the soil for decades.


It is also possible that a piece of stonewort travelled to RSPB Saltholme inside the digestive system of a duck. Stoneworts provide an important habitat for a variety of fish, molluscs and invertebrates.
RSPB Warden Ed Pritchard said: “Bearded stonewort likes brackish water, which we have at RSPB Saltholme, and thrives in disturbed soil. We will need to disturb the soil around the ponds every five or so years. If we don’t; plants such as common reed will take over and the stonewort will disappear again.”
The bearded stonewort was discovered by local botanist, Martin Hammond, he said: “I knew this was one of the rarer species, but I was amazed when national expert Nick Stewart identified it as bearded stonewort – one of Britain’s most endangered plants."
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Hide AdMartin continued: "This species is very particular about where it grows, in clean lakes or ponds at the cusp between fresh and salt water. It’s never been found in northern England before but we’re guessing it once grew un-noticed in pools or ditches at RSPB Saltholme and the spores lay dormant in the soil.”


Since the mid-twentieth century stoneworts have decreased significantly because of rapid changes in water quality due to agricultural intensification and loss of habitat. Seventeen species are currently listed as Threatened or Endangered in the Red Data Book of British Stoneworts.