Ouaisné Common

Ouaisne–        Size: 13haOuaisne
–        Main habitat types: Mature gorse, willow carr, short and long dune grassland, marram grasses, wet grassland, molinia bog and reed bed. Gorse and willow seem to be overrepresented while the site would benefit from an increase to the other habitats.

 

Ouaisne. Photo by Tim RansomThis relatively small site holds many rare and uncommon species that belong to threatened habitats, making it one of Jersey’s most important sites for biodiversity and species richness. A sand dune system progresses to heathland, with large portions of gorse, dwarf shrub heath, grassland and wetlands, as well as a large pond and reed bed. Ouaisné’s boundaries are defined by the sea wall, private housing, agricultural fields and the cliffs of Portelet Common. Traditionally, the site was used for sheep grazing up until the 17th century. Water extraction for potato crops but more significantly now for housing has impacted onto the wetter areas of the site and drying now threatens many plant and animal species at Ouaisné.

Birds and other wildlife

Grass snake. Photo by Kristian BellOuaisné is well known locally for its amphibian and reptile species. The very rare Jersey form of grass snake Natrix natrix and the green lizard Lacerta bilineata are found here, while the site is also an important breeding site for agile frog Rana dalmatina and common toad Bufo bufo. Dartford warbler Sylvia undata and common whitethroat
S. communis breed here as does reed warbler Acrocephalus arundinaceus. Stonechat Saxicola rubecula, cirl bunting Emberiza cirlus and serin Serinus serinus all Agile frog. Photo by Kristian Bellbred here until the last few years and may return with management. The wet grassland and pond are the main habitat of large numbers of invertebrates, and the whole site hosts more than 150 species of plants. Woodcock Scolopax rusticola and common snipe Gallinago gallinago winter in the wetter parts of the site.

Future management

Field cricket late instar nymph. Photo by Tim RansomThe Molinia bog at Ouaisné requires significant management. This habitat provides a home for many important species including marsh St John’s wort Hypericum elodes, lesser skullcap Scutellaria minor, agile frog, grass snake and field cricket Gryllus campestris. Molinia bogs are a wet, acidic, habitat associated with heathlands dominated by purple moor grass Molinia caerulea. In the UK, this grass is often an invasive species but in Jersey it is rare and requires management to prevent loss or degradation including the removal of species such as willow, bramble, gorse, bracken and honeysuckle which threaten to smother the purple moor grass and associated flora. These ‘problem’ plants are removed from the eastern end of the bog by cutting or pulling thereby increasing the bog’s area.

Proposed management of Ouaisné includes:

  • Reduction of mature gorse coverage by one third to make room for the expansion of other habitat types;
  • Reduction of willow cover, leaving corridors from the dune slack to the eastern fields;
  • Doubling the presence of marram grass along the top of the sea wall;
  • Tripling the extent of short turf dune grassland.