Location and General Description
The North-eastern Spain and Southern France Mediterranean forests encompass Southern France, the coastal part of Valencia and Catalonia regions in North-eastern Spain, and the Balearic islands. Geologically, the ecoregion is dominated by Mesozoic and Quaternary sedimentary rock (limestone, sandstone, marl, and conglomerate). Old crystalline substrates (granite, schist, and quartzite) characterize a few areas in the Balearic Islands (Menorca) and Catalonia (Creus Cape). The ecoregion’s coastline is characterized by cliffs, sand dunes and salt lagoon systems of outstanding biodiversity (i.e. Ebro delta, Rhone delta, Valencia Albufera). Climatically, the ecoregion experiences very hot and dry summers, and relatively temperate and humid to sub-humid winters. Annual average temperature ranges from 10-17º C, and the minimum average temperature of the coldest month ranges from 5-10º C. The annual precipitation ranges from 350-800 mm and is typified by torrential rainfalls in autumn.
The ecoregion’s forests are mainly composed of mixed evergreen and deciduous broadleaf and conifer species. Mixed evergreen (Quercus ilex, Q. suber) and deciduous (Q. pubescens in Southern France, Q. faginea in continental Spain) forests are widely spread all along the continental part of the ecoregion. A North African deciduous oak (Quercus canariensis) appears locally in the coastal mountains of northern Catalonia. The Balearic Islands only host holm oak (Q. ilex) forests, mainly on Mallorca Island.
Wild olive (Olea europaea) and carob (Ceratonia siliqua) woodlands and maquis are mainly distributed in the southern portion of the ecoregion (Valencia region and Balearic Islands). Mixed oak/stone pine (Pinus pinea) forests frequently appear on siliceous rocky slopes of the coastal ranges, while stone pine and dense maquis vegetation (Juniperus phoenicea, Pistacia lentiscus, Myrtus communis, Chamaerops humilis) characterize the coastal sand dunes. Maritime pine (Pinus pinaster) predominates on sandstone substrates in certain coastal mountain ranges, and Aleppo pine (Pinus halepensis) and holly oak (Quercus coccifera) mixed forests characterize the limestone and marl rocky mountain slopes.
Seasonally flooded river beds (known in Spain as "ramblas"), are characterized by shrub and tree species (Tamarix spp., Salix spp., Nerium oleander, Vitex agnus-castus, Populus alba, P. nigra, Fraxinus angustifolia), all well-adapted to periodical flooding. The saline wetlands support a halophytic vegetation of Salicornia herbacea and Arthrocnemum fruticosum, while less saline, better-drained areas give rise to meadows of Agropyron spp., Puccinelia spp. and Juncus maritimus.
The ecoregion includes several centers of plant diversity (Balearic Islands, Catalonian coastal ranges, Alicante Mountains) with an endemism rate between 10-20% of the total vascular plants. Examples are Viola jaubertiana, Thymus richardii, Thymelaea myrtifolia, Teucrium subspinosum, Sibthorpia africana, Scutellaria balearica, and Rhamnus ludovici-salvatoris. The Balearic Islands host 1,450 plant species, of which 180 are endemics, and 48 are endangered. The extinct Balearic species Lysimachia minoricensis has been conserved ex situ.
Large mammals are not particularly prominent in this ecoregion. It is worth mentioning the well-established European polecat (Mustela putorius), and otter (Lutra lutra), which are recovering after a period of decline.
Endangered raptor species, such as black vulture (Aegypius monachus) in Mallorca, and griffon vulture (Gyps fulvus) locally constitute important populations. Osprey (Pandion haliaetus) and Eleonora's falcon (Falco eleonorae) feed locally during the breeding season. The ecoregion has numerous areas that are internationally important for breeding, staging, and wintering birds. The Ebro Delta is a typical example of a fluvial delta. Some 30,000 pairs of waterbirds nest annually in the Ebro Delta, while mid-winter waterbird counts have recorded 180,000 individuals. Breeding species include purple heron (Ardea purpurea), little egret (Egretta garzetta), cattle egret (Bubulcus ibis), squacco heron (Ardeola ralloides), black-crowned night heron (Nycticorax nycticorax), little bittern (Ixobrychus minutus), great bittern (Botaurus stellaris), red-crested pochard (Netta rufina), black-winged stilt (Himantopus himantopus), collared pratincole (Glareola pratincola), Audouin's gull (Larus audouinii) (with 7,000 pairs in 1992, this is the largest colony in the world), whiskered tern (Chlidonias hybridus), gull-billed tern (Gelochelidon nilotica), little tern (Sterna albifrons), common tern (Sterna hirundo), and sandwich tern (S. sandvicensis). In summer, up to 4,000 non-breeding greater flamingo (Phoenicopterus ruber roseus) occur. Thousands of little egret (Egretta garzetta) and cattle egret (Bubulcus ibis) winter; as well as duck species, such as mallard (Anas platyrhynchos) (42,800 in 1989), gadwall (A. strepera) (4,119 in 1985), northern shoveler (A. clypeata) (14,200 in 1991), and red-crested pochard (Netta rufina) (6,100 in 1991); and also up to 32,000 shorebirds such as avocet (Recurvirostra avosetta) and black-tailed godwit (Limosa limosa).
The Camargue (Rhone Delta) breeding bird species include 8 heron species, Gelochelidon nilotica, Coracias garrulus, Merops apiaster, Plegadis falcinellus, Phoenicopterus ruber (the largest colony of flamingo in the Mediterranean), Glareola pratincola, and gulls. In autumn all wader species are represented. Extremely large numbers of 13 species of ducks occur in winter. During this period, tundra swan (Cygnus columbianus), white-tailed eagle (Haliaeetus albicilla), peregrine falcon (Falco peregrinus) and great egret (Casmerodius albus) are also present in the site. In total, several million individuals, out of the 356 bird species, use the Camargue.
Four of the Ebro Delta's fish species are endemic to the Iberian Peninsula (i.e. Aphanius iberus, Gasterosterus aculeatus). The delta also supports an outstanding mollusk fauna (marine and freshwater), while the saltwater channels hold a small endemic shrimp Palaemonetes zariqueyi. Herpetofauna of particular interest are the amphibians, Discoglossus pictus, Hyla meridionalis, and Triturus helveticus, and the reptile, Mauremys caspica. The most common reptiles are Lacerta viridis, Chalcides chalcides, Psamodromus hispanicus, Natrix natrix, and N. maura.
Most of the ecoregion has been intensively transformed into agricultural land, including mountain crop terraces and pastures, extensive vineyards, almond and olive groves, fruit trees orchards, and other irrigated crops. Coastal urbanization for tourism development is intensively degrading the last remaining coastal woodlands, as well as provoking an alarming situation regarding water shortage and pollution.
Types and Severity of Threats
Current human impact remains in this ecoregion, and is the result of several activities. Urbanization continues bringing house construction, quarry building, and increased water consumption. Agricultural intensification and large irrigation plans are problematic, with extensive greenhouse crops planted in coastal areas. Forest fires are devastating to the ecoregion; 98% are of human origin due to arson or negligence, sometimes as a response to land use conflicts, otherwise due to unregulated new land uses, such as tourism. Dam construction in the bordering ecoregions causes riverbeds to dry up, and channels to deviate the water to dams or from one river to another one are heavily impacting the coastal ecological dynamics. For example, the new Spanish hydrologic plan is putting the Ebro Delta at risk of disappearance, which would bring huge negative consequences to human activities and to biodiversity in this ecoregion. Other threats to the ecosystem are from road building and inadequate and overly intense hunting.
Justification of Ecoregion Delineation
This ecoregion is equivalent to the DMEER (2000) unit of the same name. The boundaries of this unit are primarily a product of the DMEER delineation process, which is responsible for northwestern and southern boundaries of the ecoregion. In general, it consists of the meso- and supra-Mediterranean Holm oak forests as well as some areas of sub- and meso-supra-Mediterranean downy oak forests in northeastern Spain, southern France, and the Balearic Islands (Bohn et al. 2000), but these vegetation units do not explain all of the boundaries of this ecoregion.
Bohn, U., G. Gollub, and C. Hettwer. 2000. Reduced general map of the natural vegetation of Europe. 1:10 million. Bonn-Bad Godesberg 2000.
Digital Map of European Ecological Regions (DMEER), Version 2000/05 (http://dataservice.eea.eu.int/dataservice/metadetails.asp?table=DMEER&i=1)Bohn, U., G. Gollub, and C. Hettwer. 2000. Reduced general map of the natural vegetation of Europe. 1:10 million. Bonn-Bad Godesberg 2000.
Digital Map of European Ecological Regions (DMEER), Version 2000/05 (http://dataservice.eea.eu.int/dataservice/metadetails.asp?table=DMEER&i=1)
Prepared by: Pedro Regato
Reviewed by: In process