Rhos Llawr Cwrt and Cors
y Clettwr, are a part of the upper River Clettwr catchment
of southwest Wales. They include the remnants of the 'red bog' described in 1957
by Stephens in her pioneer study of the otter. The NNR lies in a formerly large valley
complex of unimproved wetland. According to some of the previous owners, the
area was used mainly as rough grazing for ponies and cattle. This grazing was
extensive - most of the upper Clettwr has only been enclosed since the middle of
this century.
The management plan of
the reserve has been used for many years as the basis of
the tutorial for Conservation Management System Partnerships management
planning software.
An old hand drawn map,
now in the possession of the current owners of Llawrcwrt
Farm, Mr. and Mrs Woolley, names the main area of Rhos Llawr Cwrt as Waen
hadu - the seed field. It is possible that part of this rhos pasture was once cultivated
for black oats which were commonly grown elsewhere in Dyfed.
Burning may have been
used to control scrub development, but there is no
supporting documentation. There is evidence (exposures on site) that parts of Cors
y Clettwr were cut for peat but there are no rights of turbary.
Most of the NNR is grazed
by cattle and ponies under license from the Countryside
Council for Wales as part of the management programme for nature conservation.
The management plan involves
the conservation of the following features
1
Marsh fritillary Euphydryas aurinia - A large population exists on site which fluctuates
significantly in size but may exceed 10,000 adults in peak years.
2 Neutral grassland communities, NVC MG5, Total area 1.4ha.
3
Marshy grassland communities, NVC M23a, M23b, M25, M27, Agrostis canina/Carex
spp. grassland. Total area - 24.0 ha.
4
Vegetation mosaic of acid grassland, wet heath, mire, flush and spring and fen (basin
mire) communities, and Pingo basin mire
5 Dragonfly assemblage: A total of 16 breeding species of dragonflies/damselflies
exists.
6 Small Red Damselfly Ceriagrion tenellum
- A small population exists on site.
