Ecologists urge swimmers to report presence of blue-green algae


Ecologists at the UK Centre for Ecology & Hydrology are warning swimmers to look out for blue-green algae and to report its presence to Bloomin' Algae, an app that helps speed up public health warnings and teaches people how to recognise the risks associated with harmful algal blooms.

Also known as cyanobacteria, blue green algae has recently forced the Great East swim, held at Alton Water in Suffolk, to be postponed as a result of the recent warm, dry weather.

Blue-green algae can occur naturally in ponds, lakes, rivers, reservoirs and canals, and are toxic to anyone who swallows contaminated water or has skin contact with it. The blooms have caused the deaths of dogs, horses, fish and other animals across the UK. People who come into contact with the algae, such as open water swimmers and canoeists, could suffer skin rashes, vomiting, diarrhoea, fever or muscle and joint pain.

Professor Laurence Carvalho, a freshwater ecologist at UKCEH, who developed the app, said: “Blue-green algae tend to flourish in the UK from June to the autumn, during long spells of warm and dry weather. They are becoming more frequent due to climate change and the increasing amount of nutrients entering our waters, for example from sewage or fertilisers.

“By reporting blooms via the Bloomin’ Algae app, the public is providing a rapid, early warning about outbreaks and helping to give a comprehensive picture of these harmful blooms in [region] and across the UK."

Download the Bloomin’ Algae app for free on Google Play and the App store, or see their website for more details –

01 Cover July 21

Issue 51 July 2021

  • Linford Christie on his new interest in outdoor swimming and the secrets behind his success
  • The Icebreakers, a group using cold water swimming to support men's mental health
  • Triple-amputee and former Royal Marine Mark Ormrod on completing a 1km sea swim and inspiring others
  • James Pittar, the first blind swimmer to complete the Triple Crown of Open Water Swimming
  • The frontline workers finding solace in outdoor swimming France’s hidden wild swim spots
  • The revolution in women’s swimwear

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