Wednesday, 30 April 2014

Eely exciting times at Wrington and St Andrews primary

Year 6 at Wrington Primary school and Year 5/6 at St Andrews Primary school in
Congresbury were very excited last week to receive their very special guests who are
going to be living with them for the next few weeks - 120 glass eels!

Each class learnt about eel ‘husbandry’ and what to check for every day in the tank to
make sure that the eels are living in a healthy environment, how much food to give them
and how to keep the tank clean.

We then went on to match up pictures to display the eel’s life cycle - its fascinating and
mysterious stages of development - and to make sure we matched the correct terminology
and definitions to describe those stages. Even the correct word for the larval stage which
is ‘leptocephalus’! We also discovered the myriad of problems that eels face throughout
their life cycle - from encountering impassable flood defences on their way upstream to
being eaten by a hungry otter, or even caught by a keen fisherman in a special ‘glass eel

Then it was outside to try to get some (pretend) elvers from one end of the ‘river’ to the other. This was only possible if the elvers could escape the hungry heron, navigate the
natural boulders in the river, swim against the current and get past the lock gate. Luckily
the majority of them made it which is what we would hope happens in real life.
Unfortunately though, real elvers might find it a lot more difficult to reach the lake where
they can mature into adults and spend most of their adult life stage.

Back inside, we acted out being part of a freshwater food chain and thought about where
an adult eel and a glass eel could be in that food chain. We discovered that it wasn’t
always as simple as it seemed. And to see how food chains turn into food webs we chose
some saltwater food chains to join together to create a saltwater food web.

Next week we will see how the glass eels have progressed - have they become more
pigmented; have they grown; have they formed any interesting habits? We’ll keep you
posted. We’ll also be learning all about the water on our planet and how we have to look
after it.

Sunday, 27 April 2014

Spawn to be Wild

Launching our 'eely' exciting new project - Spawn to be Wild

We are delighted to launch our new schools project kindly funded by Bristol Water.  'Spawn to be Wild' is rearing young eels (elvers) in schools in the Congresbury area, just outside of Bristol, with a whole programme of curriculum based learning activities all based around this fascinating animal.

Children at Yatton Primary School with Jo from Avon Wildlife Trust and Patric from Bristol Water
Children in Yatton Primary, St Andrews Primary and Wrington Primary will all be carefully nurturing their elvers over the next term before releasing them into Blagdon Lake where the eels will live until they return back to sea to spawn.  Whilst their elvers are growing the children will learn all about the fascinating lives of these eels, the challenges they have to overcome to make it up our rivers and into the lakes and what they, and all their classmates, can all do to help save the eel.  
Jo Morris, Learning Development Manager for Avon Wildlife Trust with the box of elvers ready to go in the tank
The first session in school saw students learning about lifecycles and all about the barriers that these elvers have to overcome when they reach our coastlines and try to make it up the rivers, including weirs and locks as well get past hungry predators such as the heron.  Bristol Water have developed ways to help these eels and have made an 'eel pass' at Blagdon Lake where the eels can wriggle up to get over the dam wall in a bid to help these wonderful fish and the students will get to see this when they go to release their eels.
Students at Yatton Primary playing the eel challenge game

The European eel has a fascinating life-cycle; it is a catadromous species, breeding in the sea and migrating to freshwater in order to grow before returning to the sea to spawn. It is thought that all European eels spawn in the Sargasso Sea which is near Bermuda. The larvae, which look like curled leaves and are known as 'leptocephalli', drift in the plankton for up to three years, and are carried by the Atlantic currents towards our coastline. They then undergo metamorphosis into young eels; at this stage they are known as 'glass eels' because they are transparent. They become darker in colour and start to migrate up freshwater streams in large numbers; they are known as 'elvers' at this time. The eels, now called 'yellow eels' grow in freshwater spending up to 20 years in freshwater. Towards the end of this time, they become sexually mature; they turn a silvery colour and migrate back towards the sea on dark, moonless and stormy nights; during this time they are known as 'silver eels'. Upon returning to the sea, the European eel lives in mud, crevices, and under stones but no one has ever seen or recorded how these fish reproduce or where exactly.   

So the elvers in the schools tanks, that were provided by the Severn and Wye Smokery and UK Glass eels, have already had the most adventurous three years of life and eels can live up to a whopping 85 years - lets hope the elvers that are in schools now reach that grand old age.

Watch this space for more eely exciting news as Spawn to be Wild continues.