A Continent-like Geography
The mountains of
Corsica are built predominantly of granite and rhyolite
and though the island is geographically close to Italy, the mountains originate from
a thirty million year old chain of mountains that stretched across northern Spain, through
the Pyrenees and into the Alps. Since then, the land mass that includes Corsica and Sardinia has
moved south-eastwards and rotated anticlockwise to its present position. Though
the topography is dominated by igneous and metamorphic rocks there are some
sedimentary rocks, particularly along the east-coast. There are only three
small outcrops of limestone rocks, but these are disproportionately importan t for a number of endemic plants.
More than 130 plant taxa are endemic
Corsica and another 75 are
only known from the Corsican-Sardinian archipelago. Amongst these are two endemic
monospecific genera (Morisia monanthos
and Nananthea perpusilla) and a
number of other paleoendemics. Some of these endemics are widespread within the
island, such as the Corsican Hellebore (Helleborus
lividus subsp. corsicus) and the
Corsican crocus (Crocus corsicus).
Others, such as Brassica insularis
and a number of Limonium and Ophrys species, are restricted to
limited lengths of coastline and to outcrops of limestone, respectively.
History Has Aided the Conservation of
Fighting over the ownership of
Corsica and under-investment by
those rulers have encouraged emigration and has kept the population small. Between
the 8th and 18th centuries raids from pirates and slavers
forced people to inhabit villages away from the coast. Compounding the
political difficulties the mountainous terrain makes communication and transportation
difficult and restricts areas suitable for agriculture. Though potentially
destructive activities such as overgrazing, charcoal production and timber
extraction occur on Corsica they have been
moderate, at least in comparison with other Mediterranean islands. Though these
geographic and political factors have protected Corsican wildlife to some
extent, they have done little to help the Corsican citizens, who have never
been wealthy and often favoured their own leaders and system of justice over
that of their overseas rulers.
A number of different organisations are involved in conservation on the island, but the largest is the organisation of the Parc Naturel Régional de Corse (PNRC). Founded in 1972 the PNRC covers almost a third of the island and protects an abundance of wildlife. It has a much broader mission than wildlife conservation. It also aims to protect the cultural heritage and the way of life of rural
Corsica, while attempting to stimulate enterprise in the much-abandoned
villages. While the PNRC oversees conservation in the mountainous centre of the
island, many coastal sites are protected by the Conservatoire du Littoral. This
is a national organisation dedicated to protecting coastal sites. Though there
are many reserves and areas of botanical interest, two in particular deserve
mention. Firstly, the Valley of the , which has been
designated a biosphere reserve by UNESCO since 1977, and secondly, the
neighboring reserve of Scandola, which is almost entirely inaccessible by
land, but includes a large marine reserve. Together, these reserves contain
some of the best preserved habitats in the Mediterranean basin. Not only are
they importan Fango
River t for their flora, but
also for their populations of birds, reptiles, fish, amphibians and mammals.
Wetlands habitats do not instantly spring to mind when thinking of the environment of Mediterranean islands; yet they contribute greatly to the overall biodiversity of
Corsica. These habitats include coastal lagoons, marshes,
seasonal ponds, rivers, streams, alpine lakes and bogs. Along the east coast
are the largest lagoons, such as the Étang de Biguglia. A literal translation of the word "étang"
is "pond", though this is no pond, being 11km long and 2.5 km wide.
The Étang de Biguglia is an important reserve for all sorts of creeping, flying
and swimming wildlife, but it is also home to a number of rare plant species,
including Kosteletzkya pentacarpos, a
beautiful member of the Malvaceae. This species is found around the
Mediterranean basin, but only where suitable marshland habitat exists.
The tides around
Corsica do not amount to more than 40cm, so saltmarshes
like those on oceanic coasts are no t found.
Nevertheless, there are a number of saline "wetland" habitats, known
in French as sansouire. These are characterised by winter inundation with seawater
and then drying in the summer. A number
of halophytes, particularly halophytic members of the Chenopodiaceae (Salicornia, Sarcocornia etc), populate these highly saline habitats. Also near
the coast are a number of freshwater ponds, some of which dry out during the
summer. Unusual plants such as Baldellia
ophioglossifolius and Pilularia
minuta can be found in these uncommon habitats.
The Royal Fern (Osmunda regalis), which has declined across northern
is still common along streams in Corsica as
well as in inundated woodlands. It is a species of shady wet habitats on acidic
soils and in much of Europe it has been lost
where these habitats have been drained. Corsica's
rivers, streams and torrents are also home for several endemic species
including Doronicum corsicum, Hypericum corsicum and Narthecium reverchonii.
|Narthecium reverchonii Celak|
One of the unique wetland habitats of
It is interesting to note that although the species epithets corsicum, corsicus and corsica are used extensively for the islands endemic plants, a number of other names are frequently encountered, for example soleirolii, reverchonii, briquetii and conradii. These names commemorate the botanists Captain Joseph Francois Soleirol (1796-1863); Elisée Reverchon (1835-1914); John Briquet (1870-1931) and Marcelle Conrad (1897-1990). Notice that these botanists were working at a time when the flora of continental
was largely described. Yet whole habitats such as the pozzines were unknown to
scientists until the latter half of the twentieth century.
Risks To The Flora
With large areas of forests and scrub, fires are a serious issue on
Fires are usually started for one of three reasons. They may be unintentionally
started; they may be started maliciously, or they may be started intentionally to
clear land. At one time the European Union grant system for breeders of nursing
cows led to an increase in fires. Farmers were using fires to increase their
grazing land to comply with the requirements for subsidies; fortunately, these
grants have now been suspended. The EEC has actually made many positive contributions
to the island's economy including significan t funds
for fire prevention and protection on the island. There is a small army of
people involved in fire fighting and they possess an arsenal of modern
equipment such as recognisance planes and water bombers. Still, on average
about 8,200 hectares are burnt each year. While much of the vegetation of the Mediterranean can recover rapidly from fires, even these
habitats do not respond well to frequen t fires,
which contribute significantly to soil erosion.
Alien plants have been introduced to
Corsica since at least the Roman
period and many of those species, such as the Olive, are as much part of the
landscape as the native plants. Yet modern introductions, many from different
continents, present a threat to native plants. About 140 species have
naturalised on the island and many others are planted or are casual. Two of the
most destructive are the South African succulents Carpobrotus edulis and C. acinaciformis. These species form
mats over coastal rocks, eliminating all other plants. Another South African
introduction, Cotula coronopifolia,
poses a threat to wetlands. In places, this plant has become the dominant
species, eliminating practically all other herbs. A number of other potentially
damaging species have naturalised or are planted such as Prickly Pear (Opuntia ficus-indica); Bermuda buttercup
(Oxalis per-caprae) and several Eucalyptus species.
Changes in farming practices have had both positive and negative impacts on native plants. Since world war two there has been continual migration out of villages and a decline in traditional farming. The cultivation of chestnuts and the maintenance of terraces have declined in the hills, whereas in the lowlands vineyards have increased as has the growing of non-traditional crops such as kiwi fruit. At one time, the annual movements of livestock, known as transhumance, were an important element of agriculture in the mountains. However, these days the ancient mountain trackways are more frequently used as hiking trails.
Improvements in the roads and increased ownership of four wheel drive vehicles have made once remote corners of the island accessible. Even high altitude has not protected the pozzines from damage and popular hiking routes to the high mountain lakes have been rerouted where damage was occurring. With jeeps and motorbikes, tourists can visit once deserted beaches that are only accessible by rough tracks and these days damage to dune systems by motor-sports is common. Other risks include the collection of wild plants for gardens or for their medicinal properties. Wetlands are particularly vulnerable as they can easily be drained or overgrazed.
One should not overplay the risks though. Corsicans, in general, are proud of their environmental heritage and one can hardly deny the Corsicans the improvements in lifestyle that decent roads and an adequate infrastructure bring. Here, I can only give a flavour of the flora of
and hint at the conservation challenges. I encourage you to learn more about Corsica, even though you may need to learn some French to
do so. Corsica's history has protected its
wildlife to some extent, but in the future, it will be a challenge to balance
the aspirations of the people with environmental protection. Still, in this
respect, Corsica is not unique and it is
fortunate to have a population and institutions friendly towards environmental
This work by Quentin Groom is licensed under a Creative Commons Attribution 3.0 Unported License.