Owenkillew River

General site character

• Inland water bodies (Standing water, Running water) (35.1%)
  
• Bogs, Marshes, Water fringed vegetation, Fens (4.5%)
  
• Heath, Scrub, Maquis and Garrigue, Phygrana (0.2%)
  
• Humid grassland, Mesophile grassland (4%)
  
• Improved grassland (4%)
  
• Broad-leaved deciduous woodland (45.2%)
  
• Non-forest areas cultivated with woody plants (including Orchards, groves, Vineyards, Dehesas) (7%)
  

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

• 3260 Water courses of plain to montane levels with the Ranunculion fluitantis and Callitricho-Batrachion vegetation

  The Owenkillew River rises in the Sperrin Mountains in Northern Ireland and flows westwards, forming part of the Lough Foyle system. It is a large river, being ultra-oligotrophic in its upland reaches, and then gradually becoming oligotrophic and oligo-mesotrophic through its middle and lower reaches. The Owenkillew River is notable for the physical diversity and naturalness of the bank and channel, and the richness and naturalness of its plant and animal communities. Beds of stream water-crowfoot Ranunculus penicillatus ssp. penicillatus occur throughout its middle and lower reaches, typically in association with intermediate water-starwort Callitriche hamulata and large-leaved pondweeds such as broad-leaved pondweed Potamogeton natans and shining pondweed P. lucens.

• 91A0 Old sessile oak woods with Ilex and Blechnum in the British Isles

  The Owenkillew River is associated with several woodlands which in combination represent one of the best examples of old sessile oak wood in Northern Ireland. The woods contain a number of associated physical features, including waterfalls, gorges, cliffs and scattered boulder scree, which contribute to the diversity of the woodland communities. The woodland canopy is variable, but is generally dominated by sessile oak Quercus petraea with frequent downy birch Betula pubescens. The shrub layer consists of rowan Sorbus aucuparia and holly Ilex aquifolium, with hazel Corylus avellana locally frequent and occasional goat willow Salix caprea. In places, the ground flora is dominated by grasses, including wavy hair-grass Deschampsia flexuosa, and calcifuge mosses such as Rhytidiadelphus loreus. Where grazing is absent, bilberry Vaccinium myrtillus, great wood-rush Luzula sylvatica and bluebell Hyacinthoides non-scripta are dominant in the ground flora.

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

• 91D0 Bog woodland  * Priority feature

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

• 1029 Freshwater pearl mussel Margaritifera margaritifera

  The Owenkillew River rises in the eastern Sperrin Mountains in Northern Ireland and flows westwards, forming part of the Lough Foyle system. It is a large river, being ultra-oligotrophic in its upland reaches, and then becoming oligotrophic and oligo-mesotrophic through its middle and lower reaches. The freshwater pearl mussel Margaritifera margaritifera population, which is estimated to have a minimum number of 10,000 individuals, is confined to 4 km of undisturbed river channel in its upper reaches. It is the largest known population surviving in Northern Ireland.

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

• 1106 Atlantic salmon Salmo salar
• 1355 Otter Lutra lutra