The Ang Trapeang Thmor Sarus Crane Conservation Area is one of the prime bird watching sites of northwest Cambodia. The area offers a unique opportunity to easily observe a diversity of bird species including the endangered Eastern Sarus Crane, the world's tallest flying bird. The protected area is a huge reservoir created by forced labor during the Khmer Rouge regime, which harbors a unique wetland now. Besides the Sarus Crane, the reservoir harbors more than 200 species of other birds, of which 18 have been classified as globally threatened or globally near-threatened.
The Ang Trapaing Thmor Crane Sanctuary is a protected area of Cambodia on the site of a large Khmer Rouge irrigation project built during the 1970s. The sanctuary was gazetted on 1 January 1999 and covers an area of 10,250 hectares. The reserve was set aside to protect the rare Eastern Sarus Crane (Grus antigone sharpii). Prior to the discovery of the crane at Trapaing Thmor, there were thought to be fewer than 1,000 of the birds left alive in the world.
The Crane sanctuary is located in north western Cambodia, not far from the border with Thailand. The entire 10,000 hectares of the protected area is contained within Phnom Srok District of Banteay Meanchey Province. Phnom Srok district shares a border with Siem Reap and Oddar Meanchey Provinces. Reading from the north clockwise, Phnom Srok borders with Banteay Ampil and Chong Kal districts of Oddar Meanchey province to the north. The eastern border of the district is shared with Srei Snam and Kralanh districts of Siem Reap province. To the south the district shares a border with Preah Net Preah District of Banteay Meanchey. The western border of the district joins with Svay Chek and Thmor Pouk districts also of Banteay Meanchey. The sanctuary can be accessed by road from Sisophon (70 km) or Siem Reap (city) (90 km) via National Highway 6 initially then via smaller unsealed district roads to Ang Trapaing Thmor.
The site of Ang Trapaing Thmor reservoir is also the site of an ancient Angkorian causeway.
The Sarus Crane, Grus antigone is an all-year resident breeding bird in northern Pakistan and India (especially Central India and the Gangetic plains),Nepal, Southeast Asia and Queensland, Australia. It is a very large crane, averaging 156 cm (5 ft) in length, which is found in freshwater marshes andplains.
Ang Trapaing Thmor sanctuary is also an important conservation area for a number of other threatened species. One globally threatened primate species, the Long Tailed Macaque (Macaca fascicularis) is found within the sanctuary. One globally threatened ungulate species, the Eld's Deer(Rucervus eldii) and three globally threatened turtle species, the Asian Box Turtle (Cuora amboinensis), the Malayan Snail Eating Turtle (Malayemys subjriguga) and the Elongated tortoise (Indotestudo elongata) are also found within Ang Trapaing Thmor.