Clear weather over the UK has allowed marine scientists to monitor a large plankton bloom developing on the sea surface between Cornwall and the French coast.
The most impressive satellite images show a bloom stretching 1000 square kilometres (400 square miles). Scientists at Plymouth Marine Laboratory have colour coded the satellite image, with red and orange indicating the densest patches of algae.
Blooms, which are made up of billions of microscopic marine plants, can harm fisheries but the current one is not thought to be a threat – it is already dispersing.
Dr Peter Miller from PML says, ‘It’s only when you get the really dense blooms coinciding with onshore winds that push the algae towards the beaches that there can be a problem. Huge blooms are quite common in autumn’.
Plankton blooms are an important part of the marine food chain. Tiny animals called zooplankton eat these microscopic plants, and larger fish then feed on the zooplankton. So the timing of blooms can be quite crucial to fish larvae and so to fish stocks. But some can harm fish, as well as humans bathing on beaches.