Monday, 24 March 2014

After the Storm

During the coastal flood events of December 2013 to February 2014, Natural Resources Wales (NRW) staff were in the front line helping to keep the people of Wales safe from flooding. The peak sea level experienced in December 2013 was the highest recorded in Liverpool Bay during the 21 years since the tidal gauge was established, and the peak levels on January 3rd 2014 were the highest on the south and west coast of Wales for at least 16 years. The impacts on the coastline and defences have been compounded by the successive and sustained nature of the storm conditions and powerful waves over a number of tides and days.
Morfa Madryn by John Ratcliffe
At the same time as working to help affected communities, we have begun to assess the wider environmental implications of the storms. In particular we decided to carry out a simple audit of the impact on wildlife and Wales’s nature conservation sites, and to compare our findings with reports from England.

It quickly became evident that a wide range of coastal habitats were impacted by the storms, especially beaches, sand dunes, vegetated shingle and to a lesser extent saltmarsh and soft cliff. In a conservation context they included habitats of principal importance for conservation in Wales (under the Natural Environment and Rural Communities Act 2006). Huge amounts of sand were removed or moved around on our beaches, shingle ridges were driven inshore, and dunes, saltmarsh and cliff were eroded. However, our findings suggest that coastal grazing marsh in Wales was not seriously inundated, with only three reports submitted. This contrasts with the experience in England where extensive areas were submerged in the tidal surge event of 5th and 6th December 2013.
Sea Cucumber at Dinas Dinlle by D Bryn Jones

Nationally and internationally important conservation sites and their features have been affected. Records to date have identified change at 37 Sites of Special Scientific Interest and 10 Special Areas of Conservation.

A quarter of Wales’s nationally important geodiversity sites include sections of coast. Features include active processes, static landforms and stratigraphical or fossil interest exposed in coastal cliffs. The recent storms have led to large scale changes to the morphology of the coastline in some areas, and have also cleaned or ‘freshened’ many of the coastal cliffs through the removal of debris and vegetation. These fresh exposures, and new archaeological discoveries such as ancient submerged forest and peat cuttings, will require longer term scientific recording and monitoring.
Borth exposed forest by Ian Medcalf
Fortunately important coastal freshwater habitats (such as the Bosherston Lakes, Pembs) were not impacted by saltwater intrusions which could alter their ecosystems. In contrast, natural coastal lagoon environments have evolved to cope with increases in salinity. The damage to the infrastructure of the Wales Coast Path highlights the challenge of maintaining the route in dynamic environments.

The true extent of the wildlife impact will become apparent when surveys are carried out later in the year. Dormant animals may have been drowned in their hibernation sites, while amphibians could be extremely vulnerable to physiological shock from seawater. In particular, NRW staff have concerns about some rare coastal invertebrate species.

Dead Palmate Newts at Rhosneigr by Rachel Stroud
Our exposed coastal areas tend to accumulate relatively large amounts of marine litter, due to topography, and prevailing winds and currents. The storm and nature have done us a favour by collecting this material on to the land but the challenge will be to find a way to remove this litter from the marine ecosystem.

It is predicted that extreme weather events will become more frequent in future. We need to appreciate the degree of change which can occur during these events, both for people and their environment. In particular, the significant morphological change highlights the importance of ongoing coastal monitoring to inform management of not just built assets but also our natural biodiversity and geodiversity resources.

We are very grateful to all the Natural Resources Wales staff and our partner organisations who contributed to this environmental audit. Catherine Duigan, Nicola Rimington, Paul Brazier and Raymond Roberts, Natural Resources Wales. (This article appeared in edition 50 of Natur Cymru but there was not enough space for the photos.)

At Pembrey by Anne Bunker
Litter at Dwyfor by Paul Brazier
Starfish by Rhodri Dafydd
A Pearlside Maurolicus muelleri by Rowland Sharp.
Only the second record in Wales?
Glamorgan heritage coast - fall at Summerhouse Point by Paul Dunn
Aberystwyth by Paul Brazier
Peat cuttings at Fairbourne by Dave Thorpe

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