PROJECT DESCRIPTION
BACKGROUND
The 400 km west coastline of Denmark is home to a threatened area of coastal dune habitats. This area slowly emerges from the sea, as the land is continuing to rise following the last glacial period. This pristine, nutrient-poor land, mainly consisting of sand covered by coastal dune habitats, is probably the most valuable natural resource of Denmark. These coastal dunes comprise a mosaic of habitats, with the most abundant habitat types being well-preserved fixed dunes vegetation and humid dune slacks. These areas are unique and represent the only Danish land habitats with an end succession other than forest. They are, however, threatened by a lack of natural dynamic processes and invasion by the invasive Japanese Rose (Rosa rugosa) and invasive coniferous species. Other threats include the fragmentation of habitats, and loss of breeding and foraging areas for birds and other dune-inhabiting species.
OBJECTIVES
The overall objectives of the REDCOHA-LIFE project were to improve the conservation status of coastal dune habitats listed in the annexes of the Habitats Directive in Natura 2000 network sites along the Danish coast, and to significantly reduce the threats to the plant species Ligusticum scothicum and Calystegia soldanella. Project actions were also aimed at improving conditions for numerous other species of plant, bird, amphibian, reptile and insect characteristic of dune habitats.
RESULTS
REDCOHA-LIFE contributed to improving the conservation status of habitats and species listed in the annexes of the Habitats Directive and the Birds Directive in 15 project areas, within 17 Natura 2000 network sites along the Danish west coast.
The project targeted the imminent threat to dune habitats due to overgrowth of Japanese rose (Rosa rugosa). An area of more than 11 000 ha was surveyed and it was estimated that this invasive alien species (IAS) covered 100-110 ha at the beginning of the project. During the project, 42.2 ha of Japanese rose stands were treated, using various methods (tilling with bio-rotor, excavation and burying of plants, coverage by plastic foil, and grazing by goats or sheep). The Danish Nature Agency used only mechanical methods, though the partner municipalities of Thisted and Ringkjøbing-Skjern also used herbicides to eradicate the IAS on smaller areas. The methods developed for mapping and combatting Japanese rose were described and published in the guideline 'Best practice fighting Japanese Rose (Rosa rugosa) - experiences gathered during the LIFE- project LIFE REDCOHA implemented during 2013-2019', which is available on the project website.
The hydrological regime was restored on 291 ha of dunes and heathland habitats by closing existing ditches. A number of shallow waterbodies were also established, by removing the upper part (30-40 cm) of the organic layer. This helped to restore wet dune slacks and improve conditions for amphibians. The project constructed six islands suited for ground-nesting birds, which are threatened by predation from foxes, mink and racoon dogs. The 6 bird island constitute an area of 26 900 m2. By the end of the project, these were already colonised by birds. Fences were established, and grazing initiated on 43.5 ha, to enable areas to develop into different (protected) habitat types.
Invasive alien tree species Mugo pine (Pinus mugo), Sitka spruce (Picea sitchensis) and Contorta pine (Pinus contorta) were removed from 250.5 ha of decalcified dunes and wooded dunes. The project team cleared 107.8 ha of old plantations, predominately Mugo pine, to restore fixed dunes and humid dune slacks habitats. The removal of commercial plantations in the open coastal dune habitats also reduced habitat fragmentation. Additional restoration was made on 110 ha using Rural Development Programme (RDP) funding. Monitoring before and after the project interventions showed an improved condition of the Habitats Directive coastal dune habitat types, ‘Shifting dunes along the shoreline with Ammophila arenaria ("white dunes")’ (2120), ‘Fixed coastal dunes with herbaceous vegetation ("grey dunes")’ (2130), ‘Decalcified fixed dunes with Empetrum nigrum’ (2140), ‘Wooded dunes of the Atlantic, Continental and Boreal region’ (2180), and ‘Humid dune slacks’ (2190). Positive effects were due to great structural changes occurring during the project; though the full effects of the conservation actions will appear in the years to come.
Project actions significantly reduced threats to the plant species Ligusticum scothicum and Calystegia soldanella. Conditions were also improved for many other species, including natterjack toad (Bufo calamita), sand lizard (Lacerta agilis), wood sandpiper (Tringa glareola), pied avocet (Recurvirostra avosetta), little tern (Sterna albifrons), gull-billed tern (Gelochelidon nilotica), marsh fritillary (Euphydryas aurinia), dingy skipper (Erynnis tages), silver-spotted skipper (Hesperia comma), large heath (Coenonympha tullia), the grasshopper Chorthippus jutlandica, the damselfly Coenagrion armatum, the fern Pilularia globulifera, the aquatic plant Subularia aquatica, and the orchid Hammarbya paludosa. Breeding opportunities for birds, for example, were improved due to the restoration of natural hydrological conditions, and the establishment of predator-free islands.
Results were disseminated via diverse media, meetings and study visits, and networking with landowners and other stakeholders. The project team raised public awareness about the problem of IAS in dune habitats, for example, through a mobile exhibition.
Socio-economic impacts identified by project studies included potential benefits for tourism and population change; ecosystem services, particularly groundwater resources, by restoring wetlands; and local honey production by restoring dune moors.
The project implementation the Birds and Habitats directives, and the Biodiversity Strategy 2020 by developing methods against IAS. Project recommendations could prove valuable for the restoration of dune habitats and the eradication of IAS in other EU Member States.
Further information on the project can be found in the project's layman report and After-LIFE Conservation Plan (see "Read more" section).
