Like a giant plane-tree leaf in the sea, Lesvos hosts a large variety of habitats in which many rare species of flora and fauna thrive. Lesvos is the third largest island of Greece, after Crete and Evia, covering an area of 1,636 sq.kilometres and a coastline that spreads across 381 km. Its length is about 70 km and its width 40 km. It is located in the northeastern Aegean Sea, just 5 nautical miles from the coast of Asia Minor, right at the entrance to the Gulf of Adramyttion. Lesvos is characterised by few small mountains and a labyrinth of successive hills. The most significant mountains of Lesvos are Olympus (968 m.) to the south, Lepetymnos (969 m.) to the north and AI-Lias (938 m.) with Livanos (800 m.) to the west. Geologically the island is distinguished by volcanic rocks, while in the central and the southeast appear limestones. The intense volcanic activity of the island millions of years ago, created the world-famous Petrified Forest at Sigri. The characteristic shape of Lesvos is created by the two large enclosed bays in the south, the Bay of Kalloni (the ancient Pyreon Evripos), and the Bay of Gera. The first one covers an area of 120 sq.k. and it’s entrance length is 865 meters and the second one covers an area of 40 sq.k. and has an entrance length of 280 meters. Throughout the island there are dozens small rivers and streams with most important being Evergetoulas, Tsiknias, Sedountas, Mylopotamos, Potamia, Vouvaris, Prionas, Almyropotamos and Tsichliontas. The estuaries of most rivers create beautiful seashore wetlands that spread in few kilometres from one another covering almost all the coastline of the island. There are many small islands and rocky islets around Lesvos with most important being Barbalias, Aspronisia, Megalonisi, Agios Georgios, Panagia, Sedousa, Monopetra, Pohis, Kalloni, Mersinia, Agios Isidoros, Pamphylia, Thermi and Kydonas. The island presents two distinct faces, one dry and one green, formed by the arid grassland in the west and the lush pine and chestnut-tree forests to the east. The changes of the landscape create a big number of habitats making the island one of the most important areas for wildlife not only in Greece, but throughout Europe. Dry landscapes with brushwoods, rivers with reeds, wet forests, marshes, vast olive groves, hills with scattered oaks, rocky mountain peaks, golden sandy beaches with dunes, sheer cliffs, and fertile valleys create a unique mosaic, where wild nature is displayed at its best. For several years Lesvos is a leading ecotourism destination for scientists, nature lovers and travellers from all over the world. Maybe it’s not a coincidence that the island has been the homeland of the founder of Botany, Theophrastus, while here Aristotle wrote the famous “History of Animals” laying the foundation for the scientific study of Zoology.

Almost a quarter of the area is covered by olive groves, while the dense forests are spread over a fifth of the island. In the west and in the north there are hills with brushwood vegetation and scattered forests of large oaks and pine trees. The main pine species of the island is turkish pine, followed in a few places by black pine. Famous is the chestnut forest of Olympus, around the village of Agiasos, a large area that creates a permanent microclimate in which many rare plants grow. In Lesvos appear 7 species of oaks: turkey oak, kermes oak, valonia oak, pubescent oak, evergreen oak, hungarian oak and aleppo oak. Other trees of the island are foetid junipers, prickly junipers, phoenicean junipers, maples, common hazels, common myrtles, oriental plane trees, wild olive trees, mock privets, hawthorns, wild cherry trees, italian plums, almond-leaved pears, wild almond trees, Judas trees, willows, poplars, tamarisks, turpentine trees, strawberry trees, carob trees, common ashes and field elms. From the bushes here are found lentiscs, nerium shrubs, rockroses, spurges, oreganos, thorny burnets, common sages, savories, thymes and chastetrees. There are over 1,500 species of plants in Lesvos. Of these, two, Alyssum lesbiacum and Alyssum xiphocarpum, are narrow endemic to the island. Lesvos is one of the few regions in Greece and Europe where many species of the Near East are found, such as the famous Rhodododendron luteum, Haplophyllum megalanthum, Centaurea bourgaei, Centaurea reuteriana, Tulipa bithynica, orchid Epipactis persica subsp. persica, Asphodeline brevicaulis, Allium proponticum, Heracleum platytaenium, Tripleurospermum rosellum, Cerastium fragillimum, Sedum confertiflorum, Euphorbia petrophila, Hypericum aviculariifolium subsp. byzantinum, Nepeta nuda subsp. lydiae, Ziziphora taurica subsp. cleonioides, Saxifraga sibirica, Verbascum antinori and Verbascum vacillans. Plants of Lesvos that are found only in the eastern Aegean are Astragalus lesbiacus, Asperula nitida subsp. mytilinica, Paeonia mascula subsp. mascula, Dianthus anatolicus, Dianthus glutinosus, Symphytum anatolicum, Minuartia anatolica, Allium candargyi, Ferula tingitana, Anthemis pseudocotula, Anthemis aciphylla, Centaurea urvillei, Tragopogon longirostris, Lavandula pedunculata subsp. cariensis, Erysimum horizontale, Campanula lyrata subsp. lyrata, Paronychia chionaea subsp. chionaea, Silene urvillei, Hesperis balansae, Microsciadium minutum, Vincetoxicum canescens subsp. pedunculatum, Herniaria micrantha, Genista anatolica, Lupinus gredensis, Melilotus creticus, Aristolochia hirta, Inula verbascifolia subsp. heterolepis, Medicago blancheana subsp. bonarotiana, Tetragonolobus conjugatus subsp. requienii, Trifolium mesogitanum, Trigonella smyrnaea, Crocus biflorus subsp. biflorus, Iris suaveolens, Nepeta italica, orchids Epipactis turcica and Platanthera holmboei, Galium peplidifolium, Haplophyllum buxbaumii subsp. buxbaumii, Scrophularia floribunda, Verbascum aschersonii, Verbascum mucronatum, Veronica grisebachii and Viola heldreichiana. Other important species are Galanthus elwesii, Cicendia filiformis, Datisca cannabina, Sideritis sipylea, Fritillaria pontica, Lilium candidum, Papaver virchowii, Tordylium aegaeum, Anthemis wiedemanniana, Campanula delicatula, Campanula trachelium subsp. athoa, Rosularia serrata, Arum concinnatum, Helichrysum orientale, Jurinea consanguinea, Scolymus maculatus, Draba boerhaavii, Viburnum tinus subsp. tinus, Arenaria graveolens, Silene squamigera subsp. squamigera, Colchicum atticum, Colchicum soboliferum, Convolvulus scammonia, Trifolium constantinopolitanum, Trigonella cariensis, Corydalis integra, Ornithogalum boucheanum, Iris orientalis, Stachys obliqua, Myosurus heldreichii and Nigella elata. Lesvos is an important island for orchids with most significant species being Anacamptis palustris, Anacamptis sancta, Cephalanthera epipactoides, Epipactis densifolia, Himantoglossum comperianum, Himantoglossum jankae, Dactylorhiza romana, Listera ovata, Orchis anatolica, Orchis purpurea, Orchis simia, Serapias cordigera, Ophrys lesbis, Ophrys blitopertha, Ophrys reinholdii, Ophrys speculum, Ophrys umbilicata, Ophrys bucephala and Ophrys homeri.
 
Lesvos is one of the leading bird-watching destinations in Europe. Avifauna includes about 320 species, a huge number due to the position of the island upon a large migratory road, the proximity to Asia Minor, dozens of wetlands and the richness of different habitats. At the top are three Asian species, the Krüper’s nuthatch, the cinereous bunting and the pied kingfisher that are found only here throughout Europe. Predators of Lesvos include short-toed eagles, Bonelli’s eagles, marsh harriers, honey buzzards, long-legged buzzards, common buzzards, goshawks, sparrowhawks, peregrine falcons, Eleonora’s falcons, lanner falcons, red-footed falcons, kestrels and lesser kestrels. During the migrations appear imperial eagles, ospreys, lesser spotted eagles, booted eagles and spotted eagles. In Lesvos live 7 kinds of owls: eagle owls, long-eared owls, short-eared owls, tawny owls, little owls, scops owls and barn owls. The most important wetland birds are red-breasted gooses, ruddy shelducks, glossy ibises, avocets, greater flamingos, many species of herons and terns, black and white storks, spur-winged plovers, collared pratincoles and stone-curlews. Other birds of Lesvos are chukar partridges, quails, woodcocks, Audouin’s gulls, shags, woodpigeons, turtle doves, cuckoos, nightjars, swifts, hoopoes, kingfishers, bee-eaters, rollers, middle spotted woodpeckers, wrynecks, crag martins, skylarks, tawny pipits, meadow pipits, wrens, nightingales, rufous bush robins, bluethroats, black redstarts, black-eared wheatears, blue rock thrushes, song thrushes, mistle thrushes, subalpine warblers, Cetti’s warblers, fantail warblers, sombre tits, long-tailed tits, rock nuthatches, short-toed treecreepers, red-backed shrikes, woodchat shrikes, masked shrikes, black-capped jays, ravens, starlings, rose-coloured starlings, golden orioles, linnets, greenfinches, goldfinches, reed buntings, Cretzschmar’s buntings, cirl buntings, black-headed buntings and corn buntings

Amphibians in Lesvos include common toads, green toads, tree frogs, levant water frogs and rare eastern spadefoots. Herpetopanida is particularly rich with species such as balkan pond turtles, common pond turtles, greek tortoises, glass lizards, starred agamas, mediterranean house geckos, Kotschy’s geckos, balkan green lizards, snake-eyed lizards, snake-eyed skinks, sand boas, worm snakes, large whip snakes, dwarf snakes, levant montpellier snakes, grass snakes, dice snakes, Dahl’s whip snakes, cat snakes, leopard snakes and ottoman vipers. Among mammals stands out the presence of the Caucasian squirrel (Sciurus anomalus), which has come from Asia Minor and lives only in Lesvos throughout Europe. Other mammals of the island are foxes, beech martens, weasels, eastern hedgehogs, hares and common rabbits, while some wetlands of the island still host otters. From the bats stands out the endemic subspecies of the island, the lesser mouse-eared bat (Myotis blythi subsp. lesviacus), followed by the greater horseshoe bat (Rhinolophus ferrumequinum), the lesser horseshoe bat (Rhinolophus hipposideros), the mediterranean horseshoe bat (Rhinolophus euryale), the Mehely’s horseshoe bat (Rhinolophus mehelyi), the Blasius’s horseshoe bat (Rhinolophus blasii) and the greater mouse-eared bat (Myotis myotis). Unfortunately, half-breeds of wild boar have been released by hunters on the island, causing major damage to wild plants and crops. In the streams of the island live some extremely rare freshwater fishes, the Lesvos stone loach (Oxynoemacheilus theophilii), the Smyrna chub (Petroluciscus smyrnaeus) and the Bergama barbel (Barbus pergamonensis). From the invertebrates stand out species, such as the endemic snail Meijeriella canaliculata, the butterflies Maniola megala and Hipparchia pellucida, the bush-crickets Bradyporus macrogaster, Anadrymadusa ornatipennis, Pterolepis distinguenda and Saga natoliae, the locust Pezotettix anatolica, the beetles Omophlus brullei, Erodius orientalis subsp. oblongus and Probaticus peslieri, the isopod Armadillidium peraccae and the freshwater crab Potamon ibericum.