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Spawn to be Wild

Avon Wildlife Trust, in partnership with Bristol Water, are teaching children about the plight of the critically endangered European eel (Anguilla Anguilla), through their 'Spawn to be Wild' schools project.




The life cycle of eels


European eels have the most fascinating and mysterious lifecycle; they are a type of catadromous fish which means they migrate from fresh water into the sea to spawn. For centuries the eel's life history was not understood, even amongst the many fisherman who regularly caught both the larvae and the more mature stages without realising that they were related. Then in the early 1990s a Danish researcher concluded that the Sargasso Sea, in the western Atlantic near the Bahamas, was the most likely spawning ground and that the larvae slowly drift over 4000 miles towards Europe on the Gulf Stream. 


Heroic journey


We now know that after a journey of two years, the larvae metamorphose into transparent "glass eels", enter estuaries and start migrating upstream in the UK. After entering fresh water, the tiny glass eels metamorphose into elvers, miniature versions of the adult eels. And this is where the trouble begins. Weirs, locks, dams and flood defences can all act as impassable obstacles to this tiny creature's heroic journey; all seriously hampering the eel's migration upstream to a suitable site where they spend anything between six to 20 years to mature. They can grow to as much as a metre in length, before they begin their migration back to the Sargasso Sea to spawn.


Glass eels in schools


The European eel is now critically endangered, with numbers suffering a 95% decline since the 1970s, making its other name, the common eel, sadly inaccurate. But the good news is that we are working with schools to educate children about these incredibly charismatic creatures.


During 2015, Avon Wildlife Trust working in partnership with Bristol Wate and supported by Bridgwater College and the Sustainable Eel Group, put tanks of glass eels into four Bristol schools. Around 270 children helped to nurture their new classroom arrivals for a number of weeks, feeding them, and watching them grow before taking them to Blagdon Lake. Here they waved them goodbye having safely released them upriver, avoiding all the barriers the eels may have encountered on this part of their migration.


A number of educational sessions were delivered by Avon Wildlife Trust tutors within each school and during the field trips to the lake. Children learnt about lifecycles, food chains, wildlife conservation and sustainable water use, as well as exploring habitats of the native wildlife living at Blagdon Lake. 


A pupil said, "I've never seen eels before, it was a new experience. My favourite bit was learning about how the eels change."


One of the teachers commented "It's been a focal point for the school and everyone has been talking about the eels. The release was a really lovely moment. The children were so still and quiet as they watched the eels swim off. It was magical."


Living Landscapes


The eels' epic journey and the obstacles it must overcome provide a compelling example of an increasing challenge that faces wildlife today - the lack of connectivity across intensively-farmed land or through and around the concrete and tarmac of our towns and cities. 'Spawn to be Wild' forms part of Bristol Water's National Environment Programme to open up migration pathways for eels and supports Avon Wildlife Trust's 'Living Landscape' and learning strategy working to restore and create a network of connecting corridors, habitats and migration routes across our landscape - both in the countryside and urban areas.


These 'Living Landscapes' will enable eels and many other wildlife species to live their lives and get about their business just as our transport network allows us humans to do. 


Kate Marsh

Learning Development Manager, Avon Wildlife Trust