The Tmatboey Ibis Project aims to conserve some of South-east Asia’s rarest species by directly linking revenue from bird-watching tourism to maintenance of species’ populations. The site supports globally important breeding populations of two Critically Endangered Ibis species: the Giant Ibis – a near-mythical species for bird-watchers, naturalists and conservationists – and the White-shouldered Ibis – the only known nesting site in mainland Asia for this species. Many other regional specialities can be seen, including Lesser Adjutant, Pale-capped Pigeon, White-rumped Falcon, Rufous-winged Buzzard and Alexandrine Parakeets. WCS has undertaken to train local guides to lead the field birdwatching, and to establish regulations and agreements with local authorities governing the cost of trips and management of funds.

Surrounding the Tonle Sap Great Lake are natural grasslands, which flood annually with the rise and fall of the Mekong river. This unique habitat is highly threatened by conversion to agriculture. It also supports globally significant breeding populations of the endangered

Along with Prek Toal and Tmatboey, Ang Trapeang Thmor should surely figure as one of the prime birding sites of northwest Cambodia. The protected area is a huge reservoir built by the Khmer Rouge featuring extensive wet grasslands which grade into deciduous dipterocarp forest. It is most renowned for being the home of the largest-known flock of the rare Sarus Crane during the dry season (January-April). But almost 200 other species have been documented since the discovery of the site by the late Sam Veasna in 1998. At the height of the dry season – in March and April – feeding herds of the endangered Eld’s Deer can be seen at the fringes of the reservoir.

The bird sanctuary at Prek Toal core area of the Tonle Sap Biosphere Reserve is called "the single most important breeding ground in South-East Asia for globally threatened large water birds." The Biosphere covers 31,282 hectares at the north-west tip of the Tonle Sap Lake and plays host to species including Greater and Lesser Adjuncts, Black-headed Ibis, Painted Stork, Milky Stork, Spot-billed Pelican, Grey-Headed Fish Eagle and many more species. Of the three Biosphere core areas on the Tonle Sap Lake, Prek Toal is the most accessible from Siem Reap and the most popular with birdwatchers. The best time of year for viewing is the dry season when flocks of migratory birds congregate at Prek Toal. As the dry season progresses and the water recedes, the number of birds increases but the travel to some of the more important viewing areas becomes more difficult. A day trip is commended to visit the bird sanctuary with early departure.