European Eel (Anguilla anguilla)
Of all the species in our virtual safari, few have a more extraordinary travel itinerary than European Eels. By the time they reach the Weald Moors, their larvae may have spent up to three years drifting across the North Atlantic ocean in plankton before heading, as tiny Elver, into our rivers and streams. Upon reaching maturity, they are bound to return to the coast once again, on a final journey back to their breeding grounds in the Sargasso Sea.
In the Field: Eel larvae drift in on the Gulf Stream in early spring, moving inland between May and September. Wetlands and backwaters are especially desirable destinations and those with plenty of aquatic and bankside cover will generally prove attractive. Eels can survive on land for at least a couple of hours, and may even enter damp fields after dusk to feed on slugs and worms. As this behaviour might suggest, these opportunistic nocturnal predators feed on a wide variety of fish, invertebrates, and insect larvae (which are important for young eels) but, conversely, may not eat at all during the winter months.
Owing to its geography, the west coast tends to recruit a higher influx of eels than any other part of Britain, making their journey to Shropshire a little more straightforward. While they are widely distributed in our waters, the numbers making their way to northern Europe have plummeted by around 90 % in the last twenty years. Consequently, the European Eel is the only species presently found in Shropshire that is classified as ‘Critically Endangered’ on the International Union for Conservation of Nature’s global Red List. Commercial fishing, pollution and the escalation of physical barriers on waterways are all thought to have contributed to their decline but because much remains unknown about the eel’s life cycle we do not have the full story. What we do know, however, is that because eels are slow growing and potentially long-lived (to around eighty years, although twenty is thought more likely) these losses are that much harder to absorb.