Searching for the Secretive Eel of the North Kent Marshes
A project on the North Kent marshes is helping to uncover one of the biggest mysteries hidden within the ditches, creeks and waterways of the Hoo Peninsula and the Isle of Sheppey: where are our eels?
Led by the Medway Swale Estuary Partnership (MSEP) and funded through the National Lottery Heritage Fund as part of the Whose Hoo programme, volunteers have been collecting water samples from across the marshes to search for traces of eel DNA, known as environmental DNA (eDNA). This technique allows scientists to detect the presence of species without needing to catch or even see them.
Despite being one of the UK's most remarkable fish, there is currently very little information about where eels are distributed across the extensive drainage networks of the North Kent Marshes. The surveys aim to build a clearer picture of where eels are present and, ultimately, help researchers understand the health and size of local populations.
The work is particularly important because the European eel has suffered a dramatic decline in numbers in recent years, and is now considered one of Europe's most threatened migratory fish. Born in the Sargasso Sea in the Atlantic Ocean, young eels travel thousands of miles before reaching rivers, lakes and wetlands across Europe, including the marshes of North Kent.
Early survey work has already shown promise. Recent eDNA surveys on the Hoo Peninsula detected eels at more than half of the locations sampled, confirming that they are still using the marsh drainage system. The next stage of the project will focus on understanding what may be preventing them from reaching suitable habitat further inland.
One of the biggest challenges facing eels is physical barriers within watercourses. Across the Hoo Peninsula and Sheppey, tidal outfalls, sluices, culverts and other structures can restrict movement between the marsh ditches and the wider estuary network. Many of these outfalls discharge into the River Thames, River Medway and The Swale, and some are now in need of repair or improvement.
The project team hopes the survey results will help identify priority locations where barriers can be removed or modified, improving access to feeding and nursery habitat throughout the marshes. Future funding bids are expected to focus on enhancing these vital connections, helping eels complete their extraordinary journey and supporting the recovery of a species that has been part of Kent's wetlands for centuries.
