Mussel numbers in the river Thames have dropped by up to 99 per cent

Populations of native mussels in the river Thames have dropped massively between 1964 and 2020, possibly because of the effects of pollution and invasive species

By Matthew Sparkes

Mussel populations in the river Thames in the UK have dropped by as much as 99 per cent between 1964 and 2020. Why isn’t clear, but the researchers involved suspect it is down to the effects of pollution and invasive species.

To shed light on the long-term trend, Isobel Ollard and David Aldridge at the University of Cambridge replicated the earliest rigorous study available on these mussel populations, a survey on the Thames in Reading, Berkshire, dating …