Teal Lough and Slaghtfreeden Bogs ASSI

The area is of special scientific interest because it contains three sites of upland raised bog within an area of blanket peat, which together are thought to be the most extensive and least disturbed examples of this habitat type in Northern Ireland. The largest of these bogs, at Teal Lough, probably has the finest hummock and pool complex of any raised bog in Northern Ireland. On all the bogs there are scattered large hummocks of Racomitrium lanuginosum, Sphagnum imbricatum and Sphagnum fuscum, together with other bryophytes including Mylia taylorii, Mylia anomala and Pleurozia purpurea. The bog pools also support a number of locally uncommon vascular plant species, including lesser bladderwort at Teal Lough and oblong - leaved sundew at Slaghtfreeden.

The peat has developed on an underlying fluvio-glacial outwash sand and gravel series, related to the deglaciation phases of the south Sperrins iron pan formation impeded drainage, allowing peat development on an otherwise freely-draining substrate.

The bog contains a well developed pool and hummock complex and grades into thinner blanket bog on the surrounding slopes. The Sphagnum - rich bryophyte carpet is frequently disrupted by large, well-formed hummocks of Racomitrium lanuginosum, Sphagnum fuscum, and Sphagnum imbricatum. The pools support a characteristic growth of aquatic Sphagnum mosses, along with stands of bogbean and pockets of submerged lesser bladderwort. Their margins support the rare oblong-leaved sundew while the surrounding lawns of bog Asphodel support a scattering of white beak-sedge, interspersed with moss hummocks.

The surrounding blanket bog is characterised by the greater abundance of dwarf-shrubs, particularly heather and crowberry, growing over a dense acidophilous, or acid-tolerant, bryophyte carpet on the drier slopes. This becomes intermixed with swards of purple moor-grass on wetter flushed slopes.

The small oligotrophic lough which lies directly adjacent to the bog to the north is typical of base-poor lakes on open peat. It is characterised by its aquatic bryophytes, in particular Sphagnum auriculatum and Sphagnum cuspidatum, and by its impoverished nature, with a very sparse development of swamp and fen.

Although the range of species present is limited by the naturally exposed and oligotrophic conditions, the bog supports a notable upland peatland insect fauna. A large colony of the large heath butterfly is known to be centred on the intact bog area. The upland pondskater Gerris costai, a characteristic but local species of bog pools, is also common, and the shorebug Salda muelleri, for which there are few Irish records, has been found on areas of bare peat on the bog surface. The lakes on the bog support an upland oligotrophic community of aquatic insects, including the beetles Agabus arcticus, Agabus congener, Ilybius aenescens, Rhantus suturellus, Stictonectes leipdus and the waterbug Callicorixa wollastoni.

Site Related Documents

Site map (.PDF 732Kb), Citation document (.PDF 62Kb) and Views about Management document (.PDF 61Kb).