Ratanakiri Province is located in northeast part of Cambodia, 636 km from Phnom Penh by NR7/13 and 45 minutes flight. Balung is provincial capital city. Ratanakiri is a vast and untamed region covered by dense forest in the north and crossed by many large rivers such as the Sekong River, the Sesan River and the Sre Pok River and their tributaries. The numerous waterfalls and lakes doted around the area will appeal to the nature lovers. In the North-east, the Virachey National Park (Altitude 800-1,500m) is home to many rare animal and plant species.
The basic biological justification for the creation of Virachey National Park lies in the character of its major forest formation, the diversity of its flora, and the role these habitats are predicted to play in hosting a wide array of fauna. Previous surveys in contiguous, unprotected forests outside of Virachey National Park and in the border areas back in the 1990s found evidence that charismatic, globally threatened megafauna such as tigers, elephants and gaur were present, as well as rare primates such as the Yellow-cheeked Gibbon, Silver Langur and Douc Langur. However, there have been no surveys in the area since the 1990s, and most of these previously surveyed areas outside of Virachey National Park are now severely impacted by hunting and logging. Our rationale for surveying deep within National Park was to survey the biodiversity within the central section of the protected area to assess whether the aforementioned, and other, globally threatened species also occur within the core areas of the National Park.
Virachey National Park contains a variety of natural habitats (e.g. bamboo, pine forest, semi-evergreen rainforest, dry dipterocarp forest) depending on altitude, aspect, history, geology, and hydrology. The most abundant formation is tropical evergreen rainforest, much of which appears to be in primary condition. Virachey National Park massif contains a range of mountains that reach over 1400 m in altitude to the east, and over 1,500 m towards the Laos border. These high elevation sites are far from any footpaths or villages, and have never been surveyed. This remoteness has protected the area, yet it has also prevented biological assessments since it requires 5-7 days of hiking through evergreen rainforest just to reach the proposed survey site.
Ants At least 30 species were present, in addition to many unidentified Ponerinae, Myrmicinae, and Dolichoderinae.A major discovery was a colony of Gesomyrmex (possibly G. tobiasi) found in the vicinity of the camp. This genus is in the tribe Gesomyrmicini and its closest and only living relative genus is Santschiella from Africa with a single known species, G. kohli. The colony may be G. tobiasi and hence a range extension and a significant increase in the numbers of specimens known of this species, or an entirely new species of Gesomyrmex. Considering this find, and the ecological isolation of the study area, a number of new species of ants are expected among the collected specimens. Most of the species will be new records for Cambodia, as only 22 species from 6 genera are currently listed as present in this country.
Fishes. At least 37 fish species were recorded during this survey, of which at least 10 appear to be new records for Cambodia. Two of the fish specimens, Acanthocobitis sp. and Devario sp., are potentially undescribed species. None of the species are classified as globally threatened on the IUCN Red List, but this is solely due to the fact that these fishes have not yet been assessed by IUCN. Based on fish distribution records for Vietnam and Laos, several of the fish species found during this RAP survey appear to be restricted to high elevation hill streams and will therefore likely trigger Vulnerable (VU) status on the IUCN Red List based on their small global area of occupancy.
The rivers and hill streams of Virachey National Park appeared to be in excellent condition, with no signs of pollution and virtually no signs of human impact. There appeared to be healthy populations of freshwater invertebrates in all rivers and streams, which also contained large numbers of freshwater crabs, shrimps and snails.
Amphibians and Reptiles. We recorded approximately 26 amphibian and 35 reptile species, a number of which may be new to science and several others which have never previously been recorded from Cambodia. On the basis of this survey, National Park represents an area of extremely high amphibian and reptile diversity within Cambodia, and a relatively high diversity regionally. Many of the species found in the park by the team have never previously been recorded elsewhere in Cambodia, making the park of significant herpetological conservation importance for the country.