Cork oak forests are open evergreen woodlands of Quercus suber that cover roughly 22,000 km² (about 2.2 million hectares) around the western Mediterranean, in Portugal, Spain, Morocco, Algeria, Tunisia, Italy and France. Portugal holds about 34% of that area and Spain 27%, and together they supply about 80% of the world’s roughly 300,000 tonnes of cork a year, stripped from living trees every nine to twelve years. The same woodlands, called montado in Portugal and dehesa in Spain, are the last stronghold of the Iberian lynx and the Spanish imperial eagle, and in North Africa they shelter the Barbary stag, the only deer native to the continent.
Almost every conservation argument for the cork oak runs through an animal that depends on it. The sections below follow those species from Andalusia and the Alentejo to the Algerian coast, each with the place it lives and the count that tracks it.
Quercus suber: the bark that grows back every nine years
The cork oak is an evergreen tree 10 to 15 metres tall, occasionally 25 m, with a spreading crown and a trunk wrapped in a spongy layer of cork that can be 3 to 5 cm thick even on young trees. That bark is the tree’s defence against fire. Botanists class it as a pyrophyte: after a Mediterranean wildfire, a maritime pine has to regenerate from seed and a holm oak resprouts from its base, but a cork oak survives behind its insulation and simply regrows its branches.
Humans exploit the same layer. Cork can only be taken between early May and late August, when it separates cleanly from the trunk. A tree is first stripped at 25 to 30 years old, once its trunk reaches about 60 cm in circumference, and that first harvest yields low-grade “virgin cork”. Specialist extractors cut a ring around the trunk with a sharp axe, add vertical cuts, and lift the bark away in panels, leaving the reddish trunk exposed. The tree is not felled, and it will be stripped again roughly nine years later; trees still in harvest can be 150 to 200 years old, and the species can live more than 400 years.
The record holder is the Sobreiro Monumental, or Whistler Tree, at Águas de Moura in Palmela, Portugal. Planted in 1783–1784 during the reign of Queen Maria I, it has been stripped more than 20 times since 1820; its 1991 harvest alone gave over 1,200 kg of cork, enough for more than 100,000 stoppers. It was voted European Tree of the Year in 2018.
The species asks little of the soil. It grows best where mean annual temperatures run between 13 and 17 °C and rainfall between 500 and 700 mm, it tolerates −5 °C without damage, and it prefers acidic sands, granite, gneiss and slate to limestone. In Portugal, natural and planted stands cover about 750,000 hectares, and the Portuguese montado produces about half of all cork harvested worldwide.
Iberian lynx in Sierra Morena and the Guadiana Valley: from 94 animals to 2,401
No animal shows what the Iberian woodlands are worth better than the Iberian lynx (Lynx pardinus), a spotted cat of 7 to 16 kg found only on the Iberian Peninsula. In the 1950s it ranged from the Mediterranean coast to Galicia. Overhunting, habitat fragmentation and the collapse of its main prey, the European rabbit, after myxomatosis and rabbit haemorrhagic disease, cut it down to two isolated groups in Andalusia: the hills of Sierra Morena and the coastal plains of Doñana. By 2002 only 94 lynx were left.
The recovery that followed involved restoring Mediterranean woodland and scrub, restocking rabbits, and moving and releasing lynx. Through translocations and reintroductions, by 2014 its range again included the Montes de Toledo in Castilla–La Mancha, the Matachel Valley in Extremadura and the Guadiana Valley in Portugal. The 2024 census counted 2,401 animals, 2,047 in Spain and 354 in Portugal, with breeding now recorded in Valdecañas and Cornalvo Nature Park in Extremadura and in the Sierras Subbéticas of Andalusia, and a release project launched in Murcia. The species has been downgraded to Vulnerable on the IUCN Red List.
Spanish imperial eagle: nests in old cork oaks from Extremadura to Doñana
The Spanish imperial eagle (Aquila adalberti) is a dark, white-shouldered eagle with a wingspan of 1.8 to 2.2 metres, and it too breeds only in Iberia. Its stronghold is the dehesa of central and south-west Spain: Extremadura, Ciudad Real province, the north of Huelva and the Sierra Norte de Sevilla. Pairs build nests up to 1.5 m across, often in mature cork oaks or pines, lay two or three eggs between February and April, and incubate for about 43 days. A wide, old tree in open woodland, close to the rabbits of the surrounding pasture, is exactly what a working montado or dehesa provides.
By the 1960s only about 30 pairs survived, all in Spain. Power lines were a major killer: at one point in the early 1980s, electrocution and collisions caused about 80% of deaths among first-year birds. Insulating pylons, supplementary feeding, nest repairs and reintroductions turned the trend, and by 2011 there were 324 pairs, 318 of them in Spain. Portugal was recolonised in 2003 after more than 20 years without breeding, with six pairs found in 2011 and nine in 2012. Young eagles now disperse into Morocco, where uninsulated lines kill them as Spanish lines once did.
Doñana National Park, 543 km² of marsh, dunes and woodland at the mouth of the Guadalquivir, created in 1969, shelters both the imperial eagle and the lynx, along with up to 200,000 wintering waterfowl.
Black storks, Iberian pigs and the acorn months of the Alentejo montado
The dehesa is not wild forest. The name comes from the Latin defensa, fenced land, and the system, covering nearly 20,000 km² of the Iberian Peninsula, is grassland under widely spaced oaks, grazed by cattle, sheep, goats and pigs. Oaks are kept for about 250 years, and the understory is cleared every seven to ten years so that rockroses (jara in Spanish, esteva in Portuguese) do not close the gaps. The main dehesa areas lie in Portugal’s Alentejo and Algarve and in Spain’s Extremadura, Salamanca, Córdoba, Sierra Morena and Sierra de Aracena.
The animal most tied to that rhythm is domestic. Black Iberian pigs are turned out in autumn for the montanera, fattening on acorns, and at least one hectare of healthy dehesa is needed per pig. Holm oak acorns supply the bulk from November to February, but the cork oak’s late crop, together with earlier Pyrenean and Portuguese oak acorns, stretches the season from September almost to April.
Wild species use the same mosaic. The black stork, a shy forest stork with red legs and bill, has an outlying breeding population in Extremadura and Portugal, estimated at 405 to 483 pairs in 2006 and rising, while numbers fall in parts of western Europe. Some Iberian birds stay all year, but most leave between August and October, crossing at the Strait of Gibraltar to winter in West Africa, from Senegal’s Falémé basin to western Mali. Common cranes travel the other way: those breeding in northern Europe winter mainly in Portugal, Spain and northern Africa, arriving between late October and early December and leaving from February.
Barbary stag in El Kala: the North African cork forests
South of the Strait of Gibraltar, cork oak grows along the Mediterranean coast of Tunisia and Algeria, in the Maamora Forest of Morocco and up to about 1,000 metres in the hills, reaching 2,000 m in the High Atlas. Morocco supplies about 5.8% of the world’s cork, Algeria 4.9% and Tunisia 3.5%.
The flagship mammal here is the Barbary stag (Cervus elaphus barbarus), a small red deer subspecies with a dark brown coat and white spots on the flanks and back that lives in dense, humid forest in Algeria, Tunisia and Morocco. Hunted out of Morocco, it was reintroduced there in the 1990s using Tunisian animals, and one population now lives in Tazekka National Park in the Middle Atlas. Its old predators, the Barbary lion, Atlas bear and Barbary leopard, are gone or nearly gone from its range.
Its best-known refuge is El Kala National Park in Algeria’s far north-east, created on 23 July 1983 and recognised as a UNESCO biosphere reserve on 17 December 1990. Cork oak is the dominant tree, mixed with zeen oak, kermes oak, Aleppo pine and alder, and the Barbary stag is common. The park also holds six lakes, among them Lake Tonga (2,600 ha) and Lake Oubeira (2,200 ha), parts of which are Ramsar sites, and a survey from 1996 to 2010 listed 1,590 plant species and 718 animal species. Across the border in Tunisia’s Jendouba Governorate, El Feidja National Park, established on 9 June 1990 over 2,765 hectares, protects another of the last Barbary stag herds.
Italy and France hold the smallest shares of production, but cork oak is one of the most common forest trees on Sardinia, grows along Italy’s Tyrrhenian coast and in Apulia, and reaches the Dalmatian coast. A separate subspecies, Q. suber occidentalis, with semi-evergreen leaves and slower-ripening acorns, grows along Portugal’s Atlantic coast.
Phytophthora, screw caps and the future of the cork oak’s wildlife
The link between cork and wildlife is economic. Cork is usually the main income of a dehesa owner, and bottle stoppers account for around 70% of the value added in cork growing. As plastic stoppers and aluminium screw caps take market share, the woodlands lose their main earner, and ecologists warn that a decline in cork oak stands would take the habitat of the lynx and the imperial eagle with it.
The trees face disease too. The water mould Phytophthora cinnamomi attacks cork oak roots and has devastated stands, and old oaks are hard to replace: dehesa trees may be several hundred years old, so a lost woodland is not quickly regrown. Protection has had to be won locally. In 2000 the Whistler Tree itself was nearly cut down with 411 other cork oaks during illegal building work, and Portugal tightened its cork oak protection law in 2001.
The species map shows why it matters: every successful recovery in the Iberian woodland, from 94 lynx to 2,401 and from 30 eagle pairs to more than 300, has depended on large areas of open oak country staying intact. For the wider setting of these woodlands, see our guide to Spain’s geography and the hot, dry summers described in the climate of Portugal, which explains why a drought-tolerant oak with fireproof bark became the defining tree of the Alentejo.