Koshitappu Wildlife Reserve is a land of bird paradise since more than 526 species of birds are recorded here. Nepal’s total bird species is 886 so far. With comparing national figure, the Koshitappu Wildlife Reserve shares about 59 percent bird species.
In 1987, this reserve was kept under Ramsar Site, the first time for Nepal. The reserve’s has a good wetland. That is why, it is famous for bird watching and other ornithological study. Both winter and summer birds are seen here in the reserve. Generally, winter visitors are Ruddy shelduck, Bar-headed goose, Little cormorant, Demoiselle crane, Red crested Pochard, Great crested Grebe, Little Grebe, Cotton teal, Whistling teal, Merganser, Mallard, Osprey etc. The summer visitors are White-breasted waterhen, Moorhen, Common coot, Bronze-winged Jacana, Gallinule, Open billed stork, Darter, Grey heron, Pond heron, Great egret, Inter mediate egret, Little egret, Night heron, Indian River tern, Grey headed fish eagle etc.