Canary Islands dry woodlands and forests

• Category: Forest Biomes.
• Geographic Location: Northwestern Africa.
• Summary: These singular island communities, with highly diverse vegetation, are influenced by the proximity of the Sahara Desert and trade winds.

The Canary Islands is a group of seven major volcanic islands—La Gomera, El Hierro, La Palma, and Tenerife in the west; and Gran Canaria, Lanzarote, and Fuerteventura in the east—located in the Atlantic Ocean close to the northwestern coast of Africa. An archipelago, the island chain belongs to Spain and comprises 2,875 square miles (7,447 square kilometers). Due to the islands' geographic location in the tropics, vegetation communities here are determined by three main biophysical driving forces: the influence of trade winds, the proximity to the Sahara Desert, and the local topography.

Trade winds are most evident in the western islands, where the ocean moisture carried by these northeastern air currents is stopped by the main mountain barriers—such as the Teide peak at 12,198 feet (3,718 meters)—producing the “sea of clouds” effect, which produces high humidity and rainfall at altitudes above 2,625 feet (800 meters). By contrast, the southern parts of these islands and the eastern end of the archipelago undergo a rain-shadow effect characterized by drier conditions.

The African influence occurs mainly in the eastern islands, where the hot winds that blow from the Sahara Desert produce the Calima effect, which increases average temperatures and water scarcity.

The general hilly topography of the Canary Islands, derived from their volcanic origin and subsequent erosive processes, determines the existence of microclimate variations on a local scale. Based on these factors, several vegetation communities can be described according to their altitudinal range and their location in the archipelago.

Vegetation

Basal areas in all the islands are dominated by xerophytic (low-moisture) shrub communities composed of succulent plants that have adapted to water scarcity; among these are balsam spurge (Euphorbia balsamifera) and leafless spurge (Euphorbia aphylla). Near the coastline, these communities become enriched with coastal-environment plants such as Canary sea fennel (Astydamia latifolia) and dwarf sea lavender (Limonium pectinatum). Also in these areas, two species of singular dragon trees appear: common drago (Dracaena drago), distributed in the western islands, and drago (Dracaena tamaranae), limited to Gran Canaria. Also, from 656 to 1,312 feet (200 to 400 meters) are Canary palm (Phoenix canariensis) grove communities located in gullies, particularly on La Gomera and Gran Canaria.

First forestland covers occur between the upper limit of shrubland and 2,297 to 2,625 feet (700 to 800 meters). These thermophilous (heat-loving) evergreen communities are dominated by Canary juniper (Juniperus turbinatacanariensis) on the western part of the archipelago and by wild olive (Olea cerasiformis) on the eastern islands. Other trees are mocan (Visnea mocanera), rarely deciduous and widely scattered, and Atlas mastic (Pistacia atlanticus), sometimes as a shrub.

In midmountain areas above these thermophilous formations and up to 4,921 feet (1,500 meters), the transition to more humid conditions occurs, resulting in two typical evergreen hardwood forest communities: laurisilva and the fayal-brezal forest. The first, very similar to a tropical rainforest due to its dense tree canopy and its abundant herbs and ferns understory, is dominated by a group of characteristic laurel-leaved trees such as Canary laurel (Laurus novocanariensis), barbusano (Apollonias barbujana), til (Ocotea foetens), and Indian bay (Persea indica). Laurisilva occurs predominantly on the north slopes of the western islands, where the influence of wet winds is greater, and in certain southern areas with humid microclimate conditions. Fayal-brezal forest, dominated by Canary heather (Erica arboreacanariensis) and wax myrtle (Myrica faya), occurs in areas where moisture is lower.

From 3,937 feet (1,200 meters) to the timberline at 6,562 feet (2,000 meters), the upper forest communities are represented by Canary pine forest (Pinus canariensis), especially on Gran Canaria, Tenerife, and La Palma. This open forest community is characterized by its resilience in the face of wildfires due to Canary pine's high resprouting capacity.

Finally, summit areas are occupied by shrubs, mainly of the Leguminosae family. At that altitudinal range, the number of endemic herbaceous plants highlights the already rich group of Canary endemic (found nowhere else) plants.

Native Animals

While thousands of plant species are native to the Canary Islands, animal diversity isn't as varied. The islands are home to some 1,200 animal species, including the camello Canario (Camelus dromedarius), a dromedary (one hump, long limbs, and short hair) that is called a camel (two humps, short legs). It was brought to the islands from Africa in 1405, adapted to the local climate and conditions, and is now found throughout the archipelago, especially in the south of Gran Canaria and Tenerife and across the islands of Fuerteventura and Lanzarote.

More in keeping with an island's expected animal life are the offshore cetaceans, such as bottlenose dolphins and long-finned pilot whales. The La Palma giant lizard, thought to have disappeared from the islands for nearly five hundred years, was discovered again in 2007. The species population is once again on the decline due to more human development on the islands. Also declining in numbers is the El Hierro giant lizard, which grows to 7.9 inches (20 centimeters). Now a population of between 300 and 400, El Hierro giant lizards are declining due to seagull attacks and a scarcity of plant food. Increased human activity could further stress the creature's numbers. Gallotia, or western Canaries lizards, on the other hand, seem to be a very resilient genus, with representatives of at least four sub-species found all across the archipelago. These wall lizards thrive on a wide variety of fruits, and have colonized habitats from the severe volcanic slopes of Mount Teide, to riverine areas of the woodlands, to the more harsh environs near the coastlines.

One animal with growing numbers is the Barbary ground squirrel, introduced to the island of Fuerteventura in the 1960s from North Africa. Arriving as pets, some escaped to the wild and have been reproducing without check, as they have no natural predators.

Human Activity and Conservation

Human influence is a key factor in landscape configuration. In that sense, deforestation has taken place throughout the archipelago, mainly involving fayal-brezal forest and laurisilva, which have suffered the most outstanding regression. On Gran Canaria, scarcely 1 percent of the original laurisilva remains, and on Tenerife, this amount is just 10 percent. The declines are linked to the historical conversion of forests to croplands, especially for growing bananas and sugarcane, and also associated with timber extraction, firewood and charcoal appropriation, and more recently to urban sprawl and the growth of the tourism industry since the 1970s.

Further driving forest loss is fire. In 2007, wildfires ravaged an area equivalent to almost 5 percent of the archipelago. Similarly, in 2012, wildfires burned across more than 11 square miles (28 square kilometers) on La Gomera, devastating parts of Garajonay National Park, an internationally recognized ecological treasure.

Some environmental efforts have been created to stop deforestation and improve biodiversity conservation. Forest management and reforestation linked to soil conservation and water-flow management has been utilized since the 1950s, mainly with Canary pine and other pine species. Approximately one-third of total pine forest land is planted. Protected areas also have played key roles in biodiversity conservation. About 40 percent of the Canary Islands archipelago is protected in various categories. The islands have four national parks, two of which have been declared World Heritage Sites and two as MAB Biosphere Reserves by the United Nations Educational, Scientific and Cultural Organization (UNESCO). There are also eleven natural parks and twenty-six reserves.

Global warming and climate change have significantly impacted the Canary Island forests and woodlands. Changes include increased wind, drought, and intense rain, and the climate in the region is at risk of becoming tropical. Perhaps the most serious threat to the area are wildfires, such as the one that occurred in 2019. Described by experts as an "environmental tragedy," the wildfire destroyed 24,700 acres (10,000 hectares). The 2019 fire was thought to be one of the worst in history, however, another fire broke out in 2023 that was described as the worst in the Canary Islands in 40 years. The massive Tenerife wildfires destroyed 15,000 hectares of woodland.

Bibliography

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