Monte Jaizkibel reaches moderate heights of 500 m above sea level. It is located on the coast of Gipuzkoa, running parallel to the coastline, which follows a predominantly SW – NE direction in this area near the French border.

It has vegetation formations of the Pyrenean oak variety, although these are more abundant in their younger stages (pastures and heath). One very clear factor that enriches the biodiversity on Jaizkibel is how this sandstone massif works hydrogeologically. It generates a large number of small discharges which are widely distributed over the SAC, creating small “islands” of specific vegetation, of which areas with transition mires (habitat of community interest 7140) and formations of Cladium mariscus (priority habitat 7210*) are worthy of special mention due to their relation with the present project.

MOST IMPORTANT VALUES

Uniqueness
The mires on Jaizkibel are relevant due to the intrinsic value of such enclaves, which are scattered in amongst distinct habitats, enriching the biodiversity of the mosaic of grasslands, heath and thickets, as well as providing neighbouring ecosystems with resources, mainly to do with the availability of water (breeding areas and water supplies for fauna, points of recolonisation for species of flora, etc.).

Biological and ecological values
Two types of wetland with peat-forming environments can be identified: acid and calcareous. The greatest in number, due to the predominantly sandstone lithology and high level of rainfall, are acid: transition mires or acid sphagnum bogs (7140), in dynamic contact with wet heaths (4020*). They appear in areas with flowing spring water, on passes and wet slopes or on small water courses in waterlogged areas in which the water flows slowly. They are populated by flora adapted to the acidity of the substratum, the wet conditions and the consequent leaching of nutrients, such as bryophytes belonging to the Sphagnum genus. The source of water is mixed, both the fruit of runoff –surface and underground- and direct rainfall, the habitat being extremely vulnerable to the maintenance of the oligotrophic characteristics of the supply water. The soil is very waterlogged, making it highly sensitive to trampling, although, to a certain extent, this is positive as it contributes to maintaining dynamic states and healthy populations of the species that regenerate the habitat. The latter factor enhances the resilience of the system, one of the few strategies that can be addressed in the face of phenomena practically unmanageable at local level, such as Climate Change.

There is only one alkaline peat-forming environment (priority habitat 7120*) on Jaizkibel, as is only logical given its predominantly siliceous nature. Nevertheless, there is sandy limestone interspersed in amongst the silica which makes the water in the small streams that form in a small bed load quickly with carbonates and can give rise to calcareous mires. These mineralotrophic conditions are produced practically at the mouth of the stream at 3 m above sea level in an area in which the stream bed widens and a large, flat area providing suitable conditions for the establishment of this community is created. Just a few metres away, the water from the stream flows into the sea. The Cladium mariscus formation is surrounded by ferns and gorse, peppered with Pedunculate Oak (Quercus robur), young Pyrenean Oak (Quercus pyrenaica) and Maritime Pine (Pinus pinaster).

Historical and paleoecological values
The peat-forming sites at Jaizkibel are not expected to have peat deposits of relevance from a paleoecological point of view.

Habitats of Community Interest

• 1230 Vegetated Sea Cliffs of the Atlantic
• 4020* Temperate Atlantic wet heaths with Erica ciliaris and E. tetralix
• 4030 European dry heaths
• 4040* Dry Atlantic coastal heaths
• 4090 Endemic oro-Mediterranean heaths with gorse
• 6510 Lowland hay meadows
• 6230* Species-rich Nardus grasslands
• 6210 Semi-natural dry grasslands and scrubland facies on calcareous substrates
• 6210* previous habitat with important orchid sites
• 6420 Mediterranean tall humid grasslands of the Molinio-Holoschoenion
• 7140 Transition mires and quaking bogs
• 7210* Calcareous fens with Cladium mariscus and species of the Caricion davallianae
• 91E0* Alluvial forests with Alnus glutinosa and Fraxinus excelsior
• 9230 Galicio-Portuguese oak woods with Quercus robur and Quercus pyrenaica

Flora
Several species of flora present on Jazikibel are relevant due to their endangered status or because they are relicts. There are endangered species native to cliffs and coastlines (Armeria euscadiensis VU, Iris latifolia VU, Koeleria albescens VU and Radiola linoides NT), woodland (Quercus suber NT), streams (Hymenophyllum tunbrigense VU, Trichomanes speciosum VU, Woodwardia radicans VU and Dryopteris aemula NT) and peat-forming areas (Dryopteris carthusiana VU, Drosera intermedia EN, Thelypteris palustris EN, Pinguicula lusitanica NT and Spiranthes aestivalis VU). The presence of Rhynchospora fusca was cited on Jaizkibel in 1941, but it has not be located since.

Fauna
No specific information on the fauna in the peat-forming areas of Jaizkibel is available. Due to its distribution in the Autonomous Community of the Basque Country, the presence of Zootoca vivipara (Viviparous lizard) is likely.

PHOTOS