in the 19th and 20th centuries) or other forms of cultivation. The Western Ghats rise an average to 1500 m elevation above sea level. Some of the popular hill stations in the region are Munnar, Vagamon, Paithalmala, Wayanad, Nelliyampathi, Nilambur, Elapeedika, Peermade, Thekkady, Ponmudi.ow. Wildlife Most of Kerala, whose native habitat consists of wet evergreen rainforests at lower elevations and highland deciduous and semi-evergreen forests in the east, is subject to a humid tropical climate. However, significant variations in terrain and elevation have resulted in a land whose biodiversity registers as among the world's most significant. Most of Kerala's significantly biodiverse tracts of wilderness lie in the evergreen forests of its easternmost districts. Kerala also hosts two of the world's Ramsar Convention-listed wetlands: Lake Sasthamkotta and the Vembanad-Kol wetlands are noted as being wetlands of international importance. There are also numerous protected conservation areas, including 1455.4 km2 of the vast Nilgiri Biosphere Reserve. In turn, the forests play host to such major fauna as Asian elephant (Elephas maximus), Bengal tiger (Panthera tigris tigris), leopard (Panthera pardus), Nilgiri tahr (Nilgiritragus hylocrius), and grizzled giant squirrel (Ratufa macroura). More remote preserves, including Silent Valley National Park in the Kundali Hills, harbour endangered species such as the lion-tailed macaque (Macaca silenus), Indian sloth bear (Melursus (Ursus) ursinus ursinus), and gaur (the so-called "Indian bison"—Bos gaurus). More common species include Indian porcupine (Hystrix indica), chital (Axis axis), sambar (Cervus unicolor), gray langur, flying squirrel, swamp lynx (Felis chaus kutas), boar (Sus scrofa), a variety of catarrhine Old World monkey species, gray wolf (Canis lupus), and common palm civet (Paradoxurus hermaphroditus). Many reptiles, such as king cobra, viper, python, various turtles and crocodiles are to be found in Kerala—again, disproportionately in the east. Kerala's avifauna include endemics like the Sri Lanka frogmouth (Batrachostomus moniliger), Oriental bay owl, large frugivores like the great hornbill (Buceros bicornis) and Indian grey hornbill, as well as the more widespread birds such as peafowl, Indian cormorant, jungle and hill myna, Oriental darter, black-hooded oriole, greater racket-tailed and black drongoes, bulbul (Pycnonotidae), species of kingfisher and woodpecker, jungle fowl, Alexandrine parakeet, and assorted ducks and migratory birds. Additionally, freshwater fish such as kadu (stinging catfish—Heteropneustes fossilis) and brackishwater species such as Choottachi (orange chromide—Etroplus maculatus, valued as an aquarium specimen) also are native to Kerala's lakes and waterways. Historical monuments Historical monuments in Kerala include palaces, forts, and religious institutions. Notable