Aust Cliff

Features from Wildlife magazine Wildlife articles 2008 -- Spring 2008 -- ::Severn Barrage ::The Variety of life ::A year at Willsbridge ::Willsbridge comes of age ::Reaching out - Willsbridge ::Round the reserves Wildlife articles 2007 -- Autumn 2007 -- ::Thinking BIG ::Watery webs:the pond network ::Wildlife in the landscape ::Variety of life ::How to be a climate friend ::Seasonal stroll - Walborough ::Round the reserves -- Summer 2007 -- ::The Folly Farm appeal ::Weston Big Wood-biodiversity at its best ::The variety of life ::How to capture a butterfly ::How to get to know an orchid ::Seasonal stroll - WestonBigWood ::Reserves update -- Spring 2007 -- ::Folly Farm - a very special place ::Making a difference at Folly Farm ::How find the magic at Folly Farm ::Seasonal stroll at Folly Farm ::Magic spots at Folly Farm ::Batscapes ::Climate challenge ::Variety of Life - the Ponways project ::Round the reserves Wildlife articles 2006 -- Autumn 2006 -- ::The Severn Estuary ::Bird Watch results ::How to identify garden birds ::Making space for wildlife ::How does your garden grow? ::Round the reserves -- Summer 2006 -- ::Going for green ::Stand up and be counted ::Happy birthday NSLMP ::Holi day - a riot of spring colour ::Avon's species-rich grassland ::How to photograph dragonflies ::The Big Switch ::Round the reserves -- Spring 2006 -- ::How to identify winter water birds ::Make 2006 the year you... ::Invasive invasion ::Sowing the seeds: Willsbridge Mill ::Round the reserves Wildlife articles 2005 -- Autumn 2005 -- ::Indentify common funghi ::Build a hedgehog hideaway ::Big Bird Watch ::Champions for wildlife ::Round the reserves ::Seeds of the futre: Willsbridge Mill -- Summer 2005 -- ::Restoring Folly Farm ::How to become bee-friendly ::How to identify the butterflies of spring ::Save our seas ::The variety of life: hedgerows ::Round the reserves ::25 Ways to make a difference -- Spring 2005 -- ::The variety of life: water voles ::The Avon Biodiversity Action Plan ::How to take really good wildlife photos ::How to help your garden grow ::Round the reserves ::Seasonal strolls: Browns Folly ::Sowing the seeds: for wildlife for people ::Sowing the seeds: looking back

The Severn Estuary a very special place

A barrage of questions

The Government's recent Energy Review has recommended further investigation of a proposal from the Welsh Assembly for a tidal electricity-generating barrage across the Severn Estuary, stretching 12km from Brean Down to Lavernock Point. The first suggestion for a Severn barrage goes back as far as the 1840's and a serious proposal was investigated in the 1980's. This was dropped through a mixture of economic and nature conservation concerns. Since the 1980's wildlife conservation legislation has been strengthened and the estuary is now designated as a Special Protection Area under the European Union Birds Directive and is a proposed Special Area of Conservation (SAC) under the Habitats Directive. So is the high conservation interest of the Estuary again under threat?

What is important about the Severn Estuary?
The location of the Severn Estuary on the north Atlantic flyway for migratory birds means that its mudflats and saltmarshes provide feeding grounds for very high numbers of wildfowl and waders throughout the winter period, making the estuary a key refuelling station for migratory waterfowl. The birds are all adapted to feed in different ways. In winter shelduck sift though the surface mud to extract tiny snails, tens of thousands of which can be found in a square metre. Of the waders, the curlew has the longest bill and can reach lugworms buried deep in the mud. The ringed plover, in contrast, runs quickly to catch surface prey usng its short bill. At peak times the estuary is one of only half a dozen British estuaries to hold more than 100.000 waders.

What is the potential threat from a barrage?
The Severn Estuary is seen by some as an ideal candidate for energy generation because its funnel shape produces the second highest tidal range in the world with sometimes a 15m difference between high and low water at Avonmouth. The turbulent waters of the estuary carry a heavy load of sediment resulting in a very murky appearance. This dynamic, high energy environment makes the Severn a unique wildlife habitat as these extreme conditions can only be tolerated by specialised invertebrates, vast numbers of which provide food for the thousands of migrating wildfowl and waders when exposed by the tides. Any reduction in this dynamism by construction of a barrage would have a major impact upon the ecological value of the estuary. In addition, the water levels would change to allow power generation on the ebb flow, with all of the lower inter-tidal flats being submerged. It is likely that the higher areas, especially the salt-marshes, would not be inundated on spring tides. This would change both the length of exposure of existing inter-tidal feeding areas and the extent and nature of the area exposed.

The way forward
Huge amounts of energy produced in the UK are currently wasted. For instance, about 40% of electricity is lost while being transported great distances around the national grid, while much energy goes to waste from poorly-insulated buildings, even newly-built ones.

The Trust believes that a sustainable long-term energy policy for the UK has to be based primarily on a combination of: more local and smaller-scale energy production; increased energy conservation through much higher standards of insulation in our buildings, new and old; greater generation of energy from renewable sources, including wind, water and sun, and bio-fuels for transport; and the development of substantially improved public transport. While moving to this, any short-term shortages of energy may have to be temporarily met by less sustainable fuels, but this should be strictly transitional. The Government's Energy Review was disappointing because it did not try to work out how much of the UK's long-term energy needs could truly be met in sustainable ways.

The Severn Estuary certainly has huge potential for generating renewable energy, but can this done in ways that do not involve a cost to wildlife? Certainly not with a barrage.

Getting to know the Severn Estuary
Amber McCarthy is an Environmental Biology Student from the University of the West of England who has been volunteering with the Biodiversity Team since February 2006. One of her main tasks was helping to produce the new Severn Estuary leaflet which aims to raise awareness of the estuary, its wildlife and ways to enjoy it through seven accessible walks. Here she tells us about her own discovery of the estuary

“I've been over the Severn Bridge just once and that was the only time I'd really seen the estuary, so I wasn't expecting it to be that exciting. I had a list of seven walks to research and access locations to check out and I also had to take some photographs along the way. The seven walks are located at very different sites along the estuary. The sky was very dull and cloudy with a sprinkling of rain when I set out, not a
good start.

When I arrived at Bridgwater Bay the sun was trying to break through the clouds and the landscape looked beautiful. The striking colour of the estuary was the first thing that stood out, a very rich brown. Bridgwater Bay had a friendly population of cattle grazing on the fields next to the shores. Brean Down encompassed a large sandy pebbled beach with high fissured cliffs. The Down was my favourite location, it was full of plant life with extensive views along the east of the estuary. At Uphill the buttercups were so colourful, and I had to be careful where I stood as there were so many orchids. I captured some magnificent panoramic landscape shots from the top of the hill.

Severn Beach was my biggest surprise, as on approach all that is visible is the motorway, concrete walkways and the very large bridge. I couldn't imagine why anyone would want to walk there, alongside the M4. I set out east along the walkway, the tide was very far out and the stony beach was easily accessible. The surrounding land is very green and there are many benches strategically positioned along the way for optimum rest and nature watching. As I looked across the estuary the views of the Welsh countryside were reflected in the water. The combination of low lighting, extremely low tide, patchy cloud and light breeze enhanced the character of the estuary. The perfect reflections in the surface waters captured the moving vehicles on the bridge and I was mesmerised by the clarity. It was a marvellous day and I came home realising that the estuary is truly beautiful.”

For a copy of the leaflet which is produced by the Avon Biodiversity Partnership contact Lucy Rogers, Biodiversity Development Officer email lucyrogers@avonwildlifetrust.org.uk or download from www.avon-biodiversity.org.uk or from here