The Nature Commission in Guernsey is asking residents to report any sightings of European eels, a species facing a global decline. This initiative aims to gather more data on the presence and distribution of these critically endangered fish within the island's freshwater systems.
European eels have a complex life cycle known as catadromous breeding. They hatch in the Sargasso Sea in the Atlantic Ocean, spend their adult lives in freshwater environments such as rivers, lakes, and ponds, and then return to the sea to spawn. These eels are known for their strength as swimmers and nocturnal hunting habits. Some sources indicate they can live for up to 80 years.
To better understand the eel population, the Nature Commission, in collaboration with Guernsey Water, is conducting environmental DNA (eDNA) sampling in the island's freshwater ponds and streams. The eDNA sampling helps to detect the presence of species by analyzing genetic material shed by them into the water.
Ecologists have noted that freshwater habitats are shrinking due to various factors, including land clearance, drainage, improper habitat management, and pollution. This habitat degradation leads to the fragmentation and isolation of water bodies, potentially hindering the movement of eels between them. Furthermore, man-made infrastructure, such as pipes and dams along coastlines and inland waterways, can obstruct the migration of returning eels to their inland feeding grounds.
"These species are declining globally, so it would be great to understand more about populations on island," stated an ecologist. The public's assistance in reporting sightings is crucial for conservation efforts aimed at understanding and protecting the European eel population in Guernsey.