Current hot and dry weather conditions have claimed the lives of a ‘significant number’ of fish in the River Mole near Gatwick Airport.
Specialists from the Environment Agency say that perch, pike and roach have died following a fall in water oxygen levels.
Officers have been battling since the weekend to prevent further deaths and say that thousands more fish have now been saved.
They blame ‘environmental impacts caused by the current hot and dry weather conditions’ for the disaster, but they say that they now hope that oxygen levels in the river are now stable.
Environment Agency environment manager Anna Burns said: “Our officers have worked around the clock to prevent widescale fish deaths at this much-loved river. It is distressing that a large number of fish had perished ahead of our efforts, but our swift emergency response has ensured that many more will now be saved.
“We have worked in partnership with Gatwick Airport and Thames Water and we thank them for their valuable assistance regarding this incident. We will all continue to work to prevent further fish deaths and reduce potential harm to local wildlife.”
During summer the Environment Agency regularly responds to reports of fish in distress due to natural processes reducing oxygen levels in the water. Hot, sunny weather can lead to low flows in rivers and still water fisheries - ponds and lakes) -start to warm up. Small still waters are particularly susceptible.
Rescuing fish is part of the Environment Agency’s fisheries management role. Fisheries teams are trained to use aeration equipment or hydrogen peroxide to restore dissolved oxygen levels. When necessary, fish will be rescued and transferred to safety.
Members of the public are encouraged to report any sightings of fish in distress to us via a 24 emergency hotline on 0800 807060.