Fauna and Flora from Desertas
The Desertas Islands have many rare and endemic species, but it was the urgent need to preserve a small colony of Mediterranean monk seals, commonly known as seal monk, which originated the protection of this area.
The underwater fauna of the Desertas Islands is similar to the rest of the archipelago, with European and Mediterranean affinities, particularly at the level of fish and shellfish from the coast, such as chromis (Chromis limbata and Abudefduf luridus), golden grey mullet (Liza aurata), bogue (Boops boops), white seabream (Diplodus sp)., grouper (Serranus atricauda), parrotfish (Sparisoma cretense), barred hogfish (Bodianus scrofa), ornate wrasse (Thalassoma pavo), rock crab (Grapsus adscensionis), (Mediterranean slipper lobster Scyllarides latus).
Several species of turtles and cetaceans can be seen in the waters around these islands.
The Desertas Islands are an important centre for nesting seabirds, such as Cory’s shearwater (Calonectris diomedea borealis), the Madeiran storm petrel (Oceanodroma castro), Bulwer's petrel (Bulweria bulwerii) and Fea's (Petrel Pterodroma deserta). All these birds are inherently vulnerable species for which the Desertas Islands represent one of the last refuges worldwide.
Deserta Grande Island has the largest colony of Bulwer's petrel (Bulweria bulwerii) in the Atlantic and possibly in the world. The Fea's (Petrel Pterodroma deserta) nests exclusively in Bugio.
Thus, these islands play a crucial role in the conservation of these species.
As for resident birds, which are those that can be found throughout the year, stands out the Madeiran Berthelot's Pipit (Anthus bertheloti madeirensis), an endemic subspecies on the Madeira Archipelago and the Atlantic canary (Serinus canaria canaria), an endemic subspecies in Macaronesia. Birds of prey can also be seen, in particular: the Canary Island kestrel (Falco tinnunculus canariensis), an endemic subspecies of Macaronesia, the buzzard (Buteo buteo harterti) and the barn owl (Tyto alba schmitzi), an endemic subspecies on the Madeira Archipelago.
Invertebrates are another group of animals of great interest. In the group of arthropods, of note is the wolf spider (Hogna ingens), endemic to these Islands. This arachnid has a very restricted area of distribution, inhabiting only Vale da Castanheira, on the northern edge of the top of Deserta Grande Island.
Knowledge of the malacological fauna of these Islands is still somewhat sparse. However, recent studies confirm the presence of about 50 species and subspecies of land molluscs on the Desertas Islands, 44 of which are endemic and some of them exclusive.
The Madeira lizard (Teira dugesii mauli) is the only terrestrial reptile that inhabits these islands, being an endemic subspecies of the Desertas Islands.
The flora of the Desertas Islands is varied, particular and rich in specific plants from Macaronesia, with Madeiran exclusives.
The vascular flora consists of about 200 indigenous and naturalised species, of which 30% are endemic to Madeira and 10% restricted to Macaronesia.
Deserta Grande Island has the greatest diversity of habitats and plants, and has three exclusive endemic species: Sinapidendron sempervivifolium, Frullania sergiae and Musschia isambertoi.
The first studies on the vegetation of the Desertas Islands date back to Lowe (1868). Lowe defines two vegetation areas. The 1st area, called the maritime sector, goes from sea level up to 360 m, on the three islands. This vegetation is characterised by the presence of indigenous plants such as the carrot tree Monizia eduli, the Madeira levkoje Matthiola maderensis and the Madeira calendula Calendula maderensis. The 2nd area, called the mountain sector, goes from 300 m up to 480 m, on Deserta Grande Island and Bugio, which vegetation is characterised by the presence of indigenous plants such as Lotus argyrodes, the lowe Argyranthemum haematomma and Trifolium angustifolium. Applying the study of plant communities and bioclimate carried out for Madeira Island (Capelo et al, 2000) to these Islands, the Desertas Islands potentially have two forest communities, Zambujal (Olea maderensis-Maytenetum umbellatae) and the Laurisilva do Barbusano (Semele androgynae-Apollonietum barbujanae).