Article and photography by Peter Beckenham, Conservation Officer, Middle Level Commissioners
Monitoring of threatened European eels (Anguilla anguilla) has shown that 2020 will likely be the best year for the species reaching the Middle Level since 2014 when monitoring also began.
A specially designed ‘eel pass’ allows eels to be weighed and counted at the Middle Level’s main pumping station near Kings Lynn. The 2020 data is good news overall but it also showed that elvers, the youngest eels, recorded the second lowest annual total over the same time period.
Off to eat and grow in the Fens….
The young eels move into the freshwater rivers of the Middle Level from the tidal Great Ouse in a key part of their epic migration from the Sargasso Sea. Once in the Middle Level system they remain for many years before making the 3000-mile journey back to their natal grounds to spawn. On this downstream journey the pumping station is specially designed for them to pass through unaided. During their time in freshwater the eels mature, changing in size and colour from a muddy ‘yellow’ phase to become attractive ‘silver’ eels. They are an important part of the freshwater ecosystem, providing a protein-rich food source for wading birds and otters.
See you in 15 years time…..
Once common in the Cambridgeshire fens, the European eel is now listed as ‘Critically Endangered’ by the International Union for Conservation of Nature (IUCN). For a migratory species with a complex life cycle many threats have pushed them to this once unimaginable position. The climate crisis, illegal poaching and trafficking and manmade obstacles are some of the key issues they face. Fenland residents can help by reporting illegal fishing and pollution events or volunteering for wildlife surveys.
For more information contact Peter Beckenham, Conservation Officer for the Middle Level Commissioners: