The biodiversity of the Canary Islands: a unique natural treasure

The Biodiversity of the Canary Islands

The Canary Islands, located in the Atlantic Ocean about 100 km off the northwestern coast of Africa, are a group of volcanic islands that are home to one of the richest and most unique biodiversities in Europe, the result of their geographical isolation and the variety of microclimates on each island. Thanks to their geographical isolation, mild climate and varied topography, the islands have developed unique ecosystems that are home to species found nowhere else on the planet. The biodiversity of the Canary Islands is unparalleled.

The Canary Islands are the most biodiverse region in Spain. Despite its small area, it is home to approximately 17,000 terrestrial and some 8,000 marine species, figures from Canary Islands Biodiversity Data Bank. It is considered, together with the rest of the archipelagos of Macaronesia and the Mediterranean basin, part of one of the 25 global biodiversity hotspots.

This volcanic archipelago has more than 4,500 endemic species of flora and fauna, making it a true biodiversity sanctuary. The flora ranges from lush laurisilva forests, reminiscent of prehistoric jungles, to xerophilous vegetation, adapted to drier and drier environments. In terms of fauna, the Canary Islands are home to a surprising diversity of species, many of them endemic, especially in groups such as reptiles, birds and, more specifically, arthropods, which reach an incredible number of 3,328 endemic species, and which increases year after year with new discoveries (Emerson, B. & Oromí, P., 2005).

Canary Islands fauna and flora: richness and uniqueness

When we think of canary forests, the first thing that comes to mind is the Canarian laurisilva. Easily recognizable when you hear it, it is a type of subtropical, highly humid cloud forest that is home to iconic species such as the canary laurel (Laurus novocanariensis) or the tilde (Ocotea foetens). However, there are also characteristic species, although lesser-known, in the driest areas, highlighting the presence of plants such as tabaiba (Euphorbia balsamifera) and the canary cardon (Euphorbia canariensis), both adapted to water scarcity and sunny weather.

As we mentioned before, the fauna of the Canary Islands is mainly recognized for its diversity of birds and reptiles, as well as for the uniqueness of its invertebrates, due to their evolution in insular isolation. In the group of birds, two of the most emblematic species of laurisilva forests are the rabiche dove (Columba junoniae) and the turquoise dove (Columba bollii), both endemic and endangered due to habitat loss.

Also notable are species such as the Gran Canaria blue finch (Fringilla polatzeki) and the one in Tenerife (Fringilla teydea), which represent one of the few examples of finches adapted to life in canary pine forests (Pinus canariensis), because yes, not only in the Galapagos there are finches, in the Canary Islands we also have them. In fact, the canary finch has also been differentiated from the common finch, with 4 different subspecies.

As for reptiles, the giant lizard from El Hierro (Gallotia simonyi), the giant lizard of La Gomera (Gallotia bravoana) and the giant lizard of Gran Canaria (Gallotia stehlini) are iconic species, all endemic and very representative of the process of adaptive speciation on islands (Molina-Borja, M., 2002), and which are currently in danger of extinction, especially that of Gran Canaria, due to the high predation they suffer from introduced exotic species, such as feral cats (Felis catus) or the Royal California Snake (Lampropeltis californiae).

In the marine environment, the waters of the Canary Islands are home to a rich life of cetaceans, with at least 30 species observed in the region, including common dolphins (Delphinus delphis) to the sperm whale (Physeter macrocephalus), passing through orcas (Orcinus orca) and even the majestic blue whale (Balaenoptera musculus).

Lanzarote: life in a volcanic landscape

Lanzarote, known as “the island of 100 volcanoes”, is the easternmost island of the archipelago, and stands out for its volcanic landscapes and its arid ecosystem, being one of the clearest examples of the adaptation of biodiversity to these environments. Unlike other Canary Islands, Lanzarote has a really dry climate and stony terrain, which has strongly conditioned its fauna, which has adapted in a unique way to an environment with limited water resources and scarce vegetation.

Lanzarote's characteristic vegetation includes plants resistant to drought and volcanic soil, such as the aulaga (Launaea arborescens) and the verol (Kleinia neriifolia), both adapted to thrive in areas with low rainfall and high sun exposure. These plants, together with species such as sweet tabaiba (Euphorbia balsamifera), form a particular landscape in which flora has developed strategies for retaining water and protecting against intense solar radiation.

Regarding fauna, one of the most iconic inhabitants of the island is the Atlantic lizard of Lanzarote (Gallotia atlantica), an endemic species with great adaptability found in different habitats on the island, from areas of dispersed vegetation to volcanic areas. Lanzarote is also home to migratory birds that use its wetlands and protected natural areas, such as the Chinijo Archipelago Natural Park, to rest during their migratory routes, and birds such as Eleonor's falcon can be observed (Falco Eleonorae) (Martín, A., & Lorenzo, J.A., 2001). Birds such as the Cinderella shrew are also common (Calonectris diomedea) and the Canarian whale (Saxicola dacotiae), the latter endemic to Lanzarote and Fuerteventura, adapted to arid environments with scarce vegetation.

There are also frequent species of steppe birds that have made Lanzarote their home. Among them, the emblematic Hubara of the Canary Islands stands out (Chlamydotis undulata fuertaventurae), which is found mainly in sandy plains and low scrub. This endangered subspecies is exclusive to the eastern islands of the archipelago and is another symbol of the adaptation of terrestrial birds to an arid habitat (Palacios et al., 1999).

Another prominent inhabitant of Lanzarote's natural areas is the guirre (Neophron percnopterus majorensis), an endemic subspecies of the alligator found exclusively in the Canary Islands. This endangered scavenger bird plays a crucial role in the ecosystem by contributing to the cleaning of organic debris and the cycle of nutrients.

The marine ecosystem surrounding Lanzarote is also extraordinarily diverse, with an abundant life of species that inhabit its waters. Among the fish, the Canarian seahorse stands out (Hippocampus hippocampus) and the spiny drummer (Diodon holocanthus). Lanzarote also has a wide variety of marine invertebrates, such as the spider crab (Maja squinado), or the famous Jameito (Munidopsis polymorpha), the blind crab that only lives in Los Jameos del Agua. In addition, several species of sponges and anemones can be found, which are adapted to local salinity and water temperature conditions (Pascual et al., 1992).

Comparison of Canarian biodiversity with the Iberian Peninsula and the rest of the continent

The Canary Islands have a unique biodiversity compared to the Iberian Peninsula and the African continent. Due to its insularity and isolation, the archipelago is home to an extraordinary number of endemic species, adapted to their extreme geographical conditions and to the specific microclimates of each island. While the Peninsula has a greater variety of terrestrial mammals, the canary ecosystem is mainly dominated by arthropods, as well as reptiles and birds, largely due to the absence of large predators, which never reached the islands.

In conclusion, the Canary Islands represent a microcosm of natural diversity that continues to evolve under its unique conditions. From marine fauna to endemic birds and reptiles, to arthropod fauna, each island in the archipelago provides its own characteristics that enrich this biodiversity paradise, making it a space of great scientific and conservation interest (Whittaker, R.J., & Fernández-Palacios, J.M., 2007). Its contrast with continental biodiversity is evident, and highlights the importance of protecting and preserving this unique and vulnerable ecosystem in the global context, all the more so in these times where material wealth and thematic attraction predominate, which not only does not respect or care for natural environments, but also destroys them indiscriminately.

Author's anecdote

I think I am not mistaken in saying that everyone has heard of the figure of the naturalist Charles Darwin and his contribution to history and biology with the theory of “The Origin of Species”. I imagine that we will also learn that this theory is based, mainly, on the study and observation of the species of the Galapagos Islands, more specifically the finches that inhabit them. Well, it turns out that Darwin planned to visit the Canary Islands long before he was proposed to travel aboard the Beagle across the Atlantic. However, this trip did not get in the way of visiting the Canary Islands, but he took advantage of it to make them one of his first stops.

What was the problem then? In this case, the stops were short and, due to various circumstances, very little or no productive from a naturalistic point of view. Darwin's first island stopover in the Canary Islands was a real fiasco. A cholera epidemic prevents disembarkation on the island of Tenerife and all Darwin can do is admire the Teide peak from the roof of the Beagle while recovering from previous days of bad seas and dizziness. Reticent to quarantine for 12 days on board the ship, the day after its arrival, it immediately heads for the Cape Verde archipelago.

Who knows if, under other circumstances, and having allowed him to land in Tenerife, Charles Darwin could have observed the diversity of species in the Canary Islands, deciding to also visit the rest of the islands, finding the lizards and finches endemic to our archipelago and, finally, developing the Theory of Species Evolution based on these species, giving recognition and renown to the Canary Islands, rather than to those that maintain it today, the Galapagos Islands.

References:

— Emerson, B. & Oromi, P. (2005). Richness and Diversity of the Canary Islands Fauna: A Macroevolutionary and Community Perspective. Biological Journal of the Linnean Society.

— Martin, A., & Lorenzo, J.A. (2001). Birds of the Canary Archipelago. Tenerife: Turquoise.

— Molina-Borja, M. (2002). Ecology and behavior of lizards of the genus Gallotia. In M. Johnson & R. Black (Eds.), Evolution and Ecology of Canary Islands Fauna. Oxford University Press.

— Palacios, C.J., et al. (1999). The conservation status and management requirements of the Canary Islands Hubara. Bird Conservation International.

— Pascual, P.J., et al. (1992). Marine Biodiversity in the Canary Islands. Marine Science.

— Whittaker, R.J., & Fernandez-Palacios, J.M. (2007). Island Biogeography: Ecology, Evolution, and Conservation. Oxford University Press.