Ragworm spawning

Clevedon Marine Lake is a living space, filled by sea water from the Severn Estuary which is alive with marine life.  Due to its high tidal range, the estuary has one of the most extensive intertidal wildlife habitats in the UK, comprising mudflats, sand flats, rocky platforms and islands.  These form a basis for plant and animal communities typical of extreme physical conditions of liquid mud and tide-swept sand and rock. The estuary is recognised as a wetland area of international importance, and parts are designated as a Site of Special Scientific Interest.

Thanks to this rich biodiversity, a natural phenomenon occurred at Clevedon Marine Lake on Thursday 23rd May 2019.  Visitors noticed clusters of activity under the water’s surface.  The pinkish creatures skiting about were spawning ragworm.  They look a lot like an underwater millipede.  Ragworms emerge from their burrows in late spring and swim freely to spawn at the water’s surface.  The event is part of nature’s cycle and will pass as quickly as it started.

The lake remains open for use whilst this natural process works its way through.  Some swimmers continue with their laps unfazed; others prefer to wait a couple of days.  It’s part of being a semi-natural environment.

The ragworm is highly common around the UK. They live in burrows located between the high tide and low tide points on sandy and muddy beaches and are often found in areas which offer some form of shelter, such as coves, harbours and estuaries. They feed on plankton and other small particles. They are widely used by anglers for bait.