What is ‘special’ about Clegir Mawr SSSI?

Clegir Mawr has 1 special feature.

As well as the feature noted above, Clegir Mawr has other habitats that contribute to the special interest. These include coastal heath, coastal grassland, sea cliffs and scrub. This mixture of habitats is important for much of the wildlife including the (nationally scarce) golden-samphire which grows on the sea cliffs and the (locally uncommon) prickly sedge and lesser dodder (a parasitic plant (on gorse) without leaves or roots) together with more common plants, including grasses such as sheeps fescue, common bent, squirrel-tail fescue and early hair grass. Other notable plants include heather, bell heather, western gorse, spring squill and English stonecrop. Chough regularly breed nearby and feed on invertebrates on this and adjacent areas.

Unless specified below, management of this site should aim to look after these habitats and species as well as the listed feature of interest.

What do we want Clegir Mawr to look like?

Clegir Mawr should support at least 3,000 individual plants of the spotted rock-rose distributed in at least 3 areas of the site. A minimum of two thirds of the site should be short, grassy coastal heathland with heather, bell heather and western gorse with a varied structure including areas of bare ground and thin soil between shrubby heather and rocks. Other plants here should include sheep's fescue, common bent, squirrel-tail fescue, early hair-grass, spring squill, and English stonecrop.

The taller, invasive European gorse should cover less than 10% of the site with only a few scattered patches of bracken and scrub The rocky exposed coastal ridgelines should present a patchwork of coastal heath and acid and coastal grassland. The habitats should also provide feeding opportunities for foraging chough and should continue to support at least one breeding pair. Golden samphire should be frequent on the sea cliffs.

What management is needed on Clegir Mawr SSSI and why?

Although Clegir Mawr is an excellent place for wildlife it will only remain so if the necessary management continues. CCW’s aim is to work with you to ensure that this management is carried out.

What does this mean in practice?

There are a number of different factors that could affect the special features at Clegir Mawr if they are not properly managed. These are the ones we regard as most important:


Light grazing, to remove excess herbage, enables the maintenance of dwarf shrub heath where the rock-rose grows and controls the development of scrub. Horses are preferable to sheep, since they are selective grazers and allow plants to flower and set seed. Animal dung is also an important resource for many insects (and fungi) and for the animals that feed upon them such as the chough. Avoidance of Avermectin type veterinary products, especially the long lasting bolus type application, enables this natural breakdown of dung.

Burning :

Some areas at Clegir Mawr have traditionally been burnt as a management tool. Controlled burning can rejuvenate heathland and creates opportunities for germination of the spotted rock-rose. However, over-frequent or extensive burning impoverishes the invertebrate fauna and encourages gorse. It should be used sparingly as a tool to encourage correct grazing, not primarily to control the vegetation. A long-term burning plan should be agreed with CCW. No more than a tenth of the heathland area should be burnt annually and patches should not be re-burnt within 10 years, following the Heather and Grass Burning Regulations. Fire-breaks should be established. To avoid bracken invasion following burning, grazing must be maintained, particularly on deeper soils. Controlled burning reduces the risk of large accidental burns, which can devastate large areas of heathland and grassland.

Low soil fertility :

Low soil fertility helps heather and western gorse to compete against more aggressive agricultural grasses. The application of any fertiliser or slurry should be avoided and animals should not be fed with silage on the site.

Scrub control:

Small patches of scrub should be tolerated since they provide shelter and nest sites for a variety of insects, birds and other animals. If burning and grazing are unsuccessful in limiting scrub distribution it may be necessary to cut back European gorse to prevent it encroaching on the heathland areas. Scrub control should be done on a rotational small scale basis followed by grazing and should aim to restore the area of heathland and control invasive European gorse. Cutting scrub and bruising bracken (or trampling with heavy stock in late spring) is preferable to using chemicals, although stump treatment with chemicals may be the best method of ensuring the roots are killed.


Our knowledge of wildlife is far from complete. It is possible that new features of value may appear and new management issues may arise in the future, whilst other issues may disappear. This statement is written with the best information we have now, but may have to change in the future as our understanding improves. Any information you can provide on the wildlife of your site, its management and its conservation would be much appreciated.

If you would like to discuss any aspect of your SSSI, or have any concerns about your SSSI, please contact your local CCW office.

Your local office is;

Cyngor Cefn Gwlad Cymru/Countryside Council for Wales

North Wales Region

Llys y Bont,

Ffordd y Parc,

Parc Menai,


Gwynedd, LL57 4BN,

Telephone: 01248 672500

Fax: 01248 679259