The autumn is well underway here on the Mersey estuary and as the year is coming to a close, we are taking a look back at some of the species we have recorded during our routine estuary surveys in 2023.

One of the many incredible (but rarely seen) species that live in the river is the European eel. Sadly, this species is declining in many rivers around the country and are classed as critically endangered on the IUCN Red list. Barriers such as weirs and hydroelectric schemes and poor water quality making life much harder for eels in UK rivers.

The eel and the River Mersey have a long history, in fact the term ‘snig’ (a late 15th century word for eel thought to be related to the word snake) is still recognised in the Widnes and Runcorn area; the Mersey pub in Widnes was previously known as The Snig. Rumour has it that many a person has finished a long day of hard work on the river with a hot eel pie from The Snig!

At MGET we have recorded four different life stages of European eel within the Mersey estuary, from the newly arrived glass eel stage (pictured above) to the adult life stage silver eels that are just about to make the return journey to the breeding grounds in the Sargasso Sea, an area in the Atlantic ocean, about 4000 miles from UK waters.

Here at MGET we are looking at how we can try and improve connections between the river and the upstream locations that eels need to feed in and grow older. We are also using eDNA techniques to identify sites in the river where eel DNA is found. This can help us understand the impact of a barrier on the eels journey.

For anyone wanting to learn more about the complex life cycle of the humble eel, the Forth Rivers trust have created a brilliant video, and you can watch it here: