2013 marks the 75th anniversary of the work of WTSWW in the west of its patch. This month in our regular archive item we look back at some of the early work that took place at our flagship Teifi Marshes nature reserve in Pembrokeshire.

Dyfed Wildlife Trust Bulletin No. 60, December 1992

Bass Lagoon

Bass lagoon in the making

Bass lagoon in the making

Work is now underway to construct a new lagoon at the Welsh Wildlife Centre- Teifi Marshes. This has been made possible by the success of the Dyfed Wildlife Trust in becoming one of only nine Trusts to be awarded maximum funding of £5,000 by Bass plc in their Wildlife in Action campaign. Forty seven Wildlife Trusts submitted projects for consideration by Bass but only two Welsh trusts were successful in gaining full sponsorship. Judith Phillips, the Trust’s funding and development officer was presented with the cheque by television personality and RSNC vie-president Michael Palin at a recent ceremony in London.

Previous owners of the former Cardigan Wildlife Park constructed a causeway between the disused Cardigan-Whitland railway line and the slate waste that borders Rosehill Marsh and this is being removed to form the lagoon.

The causeway destroyed a considerable expanse of saltmarsh and brackish reedbed which formed part of the foreshore leased from the Crown Estate Commissioners. This isolated part of the Marsh from any tidal influence turning it into a freshwater reedbed with only a brackish influence at the margins from a poorly placed culvert. Water levels dropped and an island formed in the centre, this is being invaded by willow carr and reducing still further the expanse of reed. The area used to be a favourite habitat for Water Rail as well as large numbers of Reed Warblers and it is hoped that we may see them return.

The causeway was constructed with clay overlaid with a thin layer of slate removed from the slate-tip SSSSI that borders Rosehilll Marsh leaving a large and unsightly hole devoid of vegetation. The removal of this slate destroyed fragile habitats within the SSSI where reptiles and several rare plants were found. Flooding is already causing erosion and the area is displaying signs of instability, this coupled with pressure from the Crown Estate Commissioners to reinstate the area has led to the decision to excavate the new lagoon.

Spoil will be used to construct a bund that will have a dual purpose of retaining water and providing a screen thus preventing disturbance of birds on and around the lagoon.

There will be an area of open water covering approximately one hectare and this will include two small islands, one constructed from alluvial clay topped with slate waste and the other a floating island where, it is hoped, an artificial Otter holt will be built. There will be both deep and shallow areas of water and it will be possible to view the birds from the two new hides.

The removal of the causeway will necessitate the introduction of a new circular path and it is planned to route this along the wooded, south-facing ridge that borders the reedbed. It is this ridge that will eventually house the new visitor centre and the reinstated area will then be visible, not only by the hardy from the hides but also by those less adventurous from the comfort of the observation area on the top floor of the visitor centre.

Robin Howard, Head of Centre