Site details

UK map showing location of Migneint-Arenig-Dduallt Special Area of Conservation/Site of Community Importance.
Location of Migneint-Arenig-Dduallt SAC/SCI/cSAC


When undertaking an appropriate assessment of impacts at a site, all features of European importance (both primary and non-primary) need to be considered.

Annex I habitats that are a primary reason for selection of this site

4030 European dry heaths
Upland European dry heath at Migneint–Arenig–Dduallt is predominantly referable to NVC type H12 Calluna vulgarisVaccinium myrtillus heath. Locally at higher altitudes this shows the effects of wind-pruning, and is lichen-rich in places. Other forms of heath present include H18 Vaccinium myrtillusDeschampsia flexuosa heath, H21 Calluna vulgarisVaccinium myrtillusSphagnum capillifolium heath on damp north- to north-east facing cliffs, and H8 Calluna vulgarisUlex gallii heath at lower altitudes. The CallunaVacciniumSphagnum heath supports the Red Data Book liverwort Gymnocolea acutiloba.
7130 Blanket bogs (* if active bog)  * Priority feature
Migneint and Dduallt mark the limits of a large upland block located along the eastern fringe of Snowdonia National Park. The site supports the largest area of blanket bog in north Wales after Berwyn and is particularly significant for the extent and quality of comparatively Sphagnum-rich M19 Calluna vulgarisEriophorum vaginatum blanket mire. M18 Erica tetralixSphagnum papillosum blanket mire is also widespread, with localised representation of the bog-moss Sphagnum magellanicum and, rarely, S. imbricatum ssp. affine. Other notable species found at the site include lesser twayblade Listera cordata, tall bog-sedge Carex magellanica and few-flowered sedge C. pauciflora, here approaching the southern limit of its British distribution. The significant representation of more degraded vegetation types, including M20 Eriophorum vaginatum blanket mire, attests to a long history of anthropogenic modification including burning, grazing and moor-gripping – significant parts of the site were formerly managed as grouse moor. Large areas of dry and wet heath are also present, while soligenous mire communities feature as widespread and extensive components of the blanket mire.

Annex I habitats present as a qualifying feature, but not a primary reason for selection of this site

3130 Oligotrophic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoëto-Nanojuncetea
3160 Natural dystrophic lakes and ponds
4010 Northern Atlantic wet heaths with Erica tetralix
91A0 Old sessile oak woods with Ilex and Blechnum in the British Isles

Annex II species that are a primary reason for selection of this site

Not applicable.

Annex II species present as a qualifying feature, but not a primary reason for site selection

Not applicable.

Many designated sites are on private land: the listing of a site in these pages does not imply any right of public access.