The Effects of Zebra Muscles in the River Thames

A single muscle can filter up to 40 liters of water in a day so you can imagine the amount of water filtration that's going on across the river. So what's the cause? What's behind this dramatic decline? One clear reason that we found is the fact that this site's been invaded by Zebra muscles which are a non-native species to the UK and they're now found in fairly high densities in the river Thames. There's probably also been wider ecosystem degradation so things like pollution. We think that might be contributing to their slower growth rates.