survey of Tenerife,Canary islands, Spain
Following the XVII IBC Congress,
CBM staff ( A. & P.
Gillison) conducted a brief survey of the
extraordinary vegetation of Tenerife. The main reason
for this visit was to help fill important gaps in the
global database represented by the Canary island (Macaronesian)
vegetation that occupies an unusual climatic regime.
Our contact and kind host was Prof. José Maria
Fernández-Palacios of the University of la Laguna,
The following descriptive notes have been extracted
from the World Wildlife Fund for Nature (WWF) website: http://www.worldwildlife.org/wildworld/profiles/terrestrial/pa/pa1203_full.html
The Canary Archipelago is a group of volcanic islands
and rock islets found in the Macronesia region, which
also includes Salvajes, Madeira, Azores and Cape Verde
Islands. The Canaries are located in the Atlantic Ocean,
between 27º 20’ and 29º 25’north
and between 13º 20’ and 18º 10’ west.
This ecoregion includes the five western islands: La
Palma, Hierro, Gomera, Tenerife, and Gran Canaria.
The western islands are younger than the eastern group
and are more mountainous, with well-developed forests.
The eastern islands are lower are drier and are included
here within the Mediterranean Acacia-Argania Dry
Woodland and Succulent Thicket ecoregion.
Despite their proximity to Africa (in latitudes similar
to those of the Sahara, Egypt and Saudi Arabia), the
Canaries show a wide range of different microclimates
apart from sub-desert landscapes. This is caused by
several factors such as elevation and orientation,
but especially because of the influence of northeast
to southwest sea winds, called alisios.These
relatively hot winds become cooler and more humid as
they pass over the sea surface. Once the alisios reach
the northern parts of the higher Canary Islands, this
moisture is trapped by the dense laurisilva and fayal-brezal
(heath) vegetation on the mountain slopes. Low-lying
islands with elevations under 750 m receive no rain
from the passing alisios so that habitats and climate
here are drier and similar to the southern parts of
the higher islands. The Canary Island Archipelago was
formed by undersea volcanic activity. There have also
been eruptions on emergent islands, with the most recent
one occurring in La Palma in 1971. La Palma and El
Hierro are the youngest islands, only 2-3 million years
old. Because of the islands’ origin, all materials
in the Canaries are volcanic and, depending on the
substances composing the lava, they can be grouped
into the following types: Traquitic-fonolitic, basaltic
and traquibasaltic rocks, and Piroclastic and slag
materials. Different soil types have been produced
due to the effects of vegetation, local weather conditions
and topography on these volcanic materials (Bacallado
et al. 1984, González et al. 1986).
Each of the habitats recognised in the Canaries grows
on a specific kind of soil. The following are soil descriptions
for dry woodlands and forests. Canarian endemic pine
forests grow on two kinds of fertile soil: ancient red
lands. Endemic Macronesian heaths are located in humid
zones in young soils composed of hydrated aluminic silicates
with a high level of organic material. Laurisilva occurs
on recent materials in places with well-defined seasons
and medium to low organic
substance levels which lie above older soil types.
The Canary Islands lack river systems. In spite of
that and owing to the steep topography of the western
islands, they are crossed by complex systems of ravines
produced by water erosion over thousands of years.
These gullies serve as drainage for winter rainfall
and, on the higher islands like Tenerife, water from
the thawing snow and ice flows year-round. Other islands
become dry in summer. Vegetation can be described according
to elevation zones. At the lowest elevation, coastal
vegetation grows, including types typical of cliffs
and sandy regions. Endemic palm groves (Phoenix
canariensis), and semiarid vegetation.are present.
Generally, these vegetation types occur from sea level
to 600 m in the north and up to 1,000 m in the south,
and include many endemic taxa. Endemics are mainly
found to be from the Euphorbiaceae, for example, Euphorbia
canariensis, and E. balsamifera . Other
important endemic species are Ceropegia fusca, Plocama
pendula, Salvia canariensis, Argyranthemum
frutescens, Rumex lunaria, Convolvulus
floridus, and Messerschmidia fruticosa (Bramwell
and Bramwell 1983, González et al. 1986 , Strasburger
et al. 1986).
Along the transition zone from 50 to 500m, between
the sea level coastal community and giving way to laurisilva
vegetation, there are thermophiles and pre-steppe bush
The species found here are common to both the lower
and higher vegetation formations. This zone has been
damaged for decades because of its good potential for
crops. Some of the endemic and representative species
are Bosea yervamora, Echium strictum, Greenovia
aurea, Aeonium sp., Monanthes laxiflora, Campylanthus
salsoloides, Forsskaolea angustifolia,
and Dracaena draco (Bramwell and Bramwell
1983, González et al. 1986).
Humid and shady laurisilva forest grows between 500
and 1400 m in elevation, with some species reaching
more than 20 m in height. Some 20 million years ago,
this evergreen forest covered large areas of the world.
However, because of the dramatic weather changes experienced
in the Quaternary, it has only survived in a few places.
This is one of the jewels of vegetation biodiversity
in the Canary Islands; the best conserved of all Macronesian
laurel forest can be found here. Even though laurisilva
is formed by several taxa grouped in different families,
there are four representative speciesfrom all of Lauraceae.
They are: Ocotea foetens, Apollonias barbujana, Laurus
azorica, and Persea indica. Other Macronesian
endemic species found in laurisilva are Arbutus
canariensis, Ilex canariensis, Visnea
mocanera, Picconia excelsa, Heberdenia
excelsa, Salix canariensis, and Viburnum
tinus (Bramwell and Bramwell 1983, González
et al. 1986).
Endemic Macronesian heaths, also known as fayal-brezal, grow from 500 to 1,700
m, as transition vegetation between laurisilva and Canarian endemic pine forests,
with which they share some species (Ilex canariensis, I. perado, Larus azorica, and Picconia
excelsa). There are three distinctive species Myrica faya, Erica arborea and E.
scoparia. Three different patterns of distribution can be seen. The first
one is the contact zone with laurisilva, where Myrica spp. are dominant,
with some Erica spp.; the second one is the typical fayal-brezal association
(Myrica-Erica); and finally the third one is the contact zone with pine
forests where Erica spp. are more common than Myrica spp. (González
Canarian endemic pine forests (Pinus canariensis) are found almost at
sea level in southern areas but in the northern parts of the islands are found
from 1,200 to 2,400 m in elevation. Finally, vegetation grows in the high mountains
above 2,000 m on La Palma and Tenerife. Some of the typical species of this vegetation
can also be found occasionally on other high islands of the archipelago that
hold the following climatic attributes: very low humidity level, scarce rainfalls,
very cool winters (-16ºC occasionally registered), warm summers (sometimes
more than 46ºC), high isolation year-round, and big contrasts of day/night
temperatures. Both endemic species and genera are found and these include Spartocytisus
supranubius, Erysimum scoparium, Nepeta teydea, Plantago
webbii, Senecio palmensis, Juniperus cedrus, Polycarpaea
tenuis, and Echium sp.(Bramwell and Bramwell 1983, González
et al.1986, Marzol 1998).
All the Canary Islands are like small isolated continents.
They are unique for their high level of endemic taxa. Not only species, but even
many genera are exclusive to this ecoregion. Every family of plants found in
the Canary Islands has endemic representatives, often including endemic genera.
Endemism levels are especially high in invertebrates, vascular plants and vertebrates
(100% of native terrestrial reptiles). Over a quarter of the 1,992 vascular plants
found on the Canary Islands are endemic to these islands (Machado 1998). Endemicity
in non-migratory vertebrates is 17.2%, or 21 out of 122 species (Machado 1998).
Among arthropod invertebrates, 44.4% of the 6,378 species are endemic (Machado
1998). For non-arthropod invertebrates, endemism is 28.8% out of 774 species
- Bacallado, J.J., M. Báez, A. Brito, T. Cruz,
F. Domínguez, E. Moreno, and J.M. Pérez.
1984. Fauna (marina y terrestre) del Archipiélago
Canario. Ed. EDIRCA S.L.
- Bramwell, D. and Z. Bramwell. 1983. Flores silvestres
de las Islas Canarias. 2nd Edition. Ed. Rueda. González,
M.N., J.D. Rodrigo, and C. Suárez. 1986. Flora
y Vegetación del Archipiélago Canario.
Ed. EDIRCA S.L.
- Machado, A. 1998. Biodiversidad. Un paseo por el
concepto y las Islas Canarias. Ed. Cabildo Insular
- Martín, A. 1987. Atlas de las aves nidificantes
en la isla de Tenerife. Instituto de Estudios Canarios.
Monografía XXXII.Marzol, M.V. 1998. El Clima.
Geografía de Canarias. 2nd Edition. Ed. Interinsular
- Strasburger, E., F. Noll, H. Schenck, and A.F.W.
Schimper. 1986. Tratado de Botánica. 7th Edition.
Although our survey was limited to a very short period
(25 -31 July), we were able to traverse most of the
key vegetation types on Tenerife. Of all the vegetation
types that range throughout the Canaries, Tenerife
offers the widest representation. Due to kind weather
and exceptionally good road systems, we were able to
photograph a wide range of plant types (examples below)
and record detailed VegClass data from 9 transects
across 38m – 2223m elevation. These data have
made a valuable contribution to the CBM global database
and significantly extended both climatic and plant
morphological coverage. We are much indebted to Prof.
Fernández-Palacios for his valuable assistance
both in introducing us to the extraordinary vegetation
of Islas Canarias and for subsequent help in identifying
plant voucher specimens from the transects.