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 the 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, the dhole, and the Asian palm civet (Paradoxurus hermaphroditus). . Reptiles Many reptiles, such as tree snake, green snake, king cobra, viper, python, and various turtles and crocodiles are to be found in Kerala — again, disproportionately in the east. Kerala has about 453 species of birds such as the Sri Lanka frogmouth (Batrachostomus moniliger), leaf picking bird, 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 mynas, the Oriental darter, black-hooded oriole, greater racket-tailed and black drongoes, bulbul (Pycnonotidae), species of kingfisher and woodpecker, jungle fowl, Alexandrine parakeets, and assorted ducks and migratory birds. Additionally, freshwater fish such as kadu (stinging catfish) and brackishwater species such as Choottachi (orange chromide — Etroplus maculatus; valued as an aquarium specimen) also are native to Kerala's lakes and waterways. List See also List of odonata of Kerala List of butterflies of Kerala List of amphibians of Kerala List of reptiles of Kerala List of birds of Kerala List of mammals of Kerala Notes Idukki is the district having more forest land in Kerala while Alappuzha has no forest land. References . Kerala Environment of Kerala Tourism in Kerala