The IBA is located in the south of the Karakalpak Ustyurt in the Asske-Audan depression. In the past the southern parts of the Assake-Audan and Sarykamish Depressions formed a common lake basin through which the Amudarya flowed and where the Uzboy river began flowing into the Kaspiy. Currently this is rather deep depression is difficult to access and has well-marked precipices in some places. There are several artesian wells with brackish water in the depression. There are dense thickets of reed and tamarisk around the wells covering about 2.5 km2.
The site includes part of the depression and the adjoining highlands in the north and north-west with Haloxylon forests.
The number of species occurring at Assake-Audan is not known accurately as it is a place where many species passing the Ustyurt Plateau stop. Their occurrence is connected with the availability of water. Also Assake-Audan is situated between the Kaspiy, the Aral and the northern part of Sarykamysh lake so that it functions as a staging post for birds on several intersecting of flyways. Two days of IBA fieldwork recorded Ardea cinerea, Accipiter nisus, Circus cyaneus, Rallus aquaticus, Calandrella rufescens, Hirundo rustica, Motacilla alba, Luscinia svecica, Cettia cetti, Sylvia curruca, Phylloscopus collybita, Fringilla coelebs, Fringilla montifringilla, Rhodospiza obsoletus, Passer domesticus, Sturnus vulgaris, Emberiza bruniceps and Corvus frugilegus. The remains of a dead gull were also found.
Non-bird biodiversity: The mammal fauna is very similar to that of the Ustyurt in general. Typical species include Ovis vignei (UzRDB) which was present in 1956; and Gazella subgutturosa (UzRDB) and Saiga tatarica (RL). Paraemichinus hupomelas (UzRDB) and Testudo horsfieldi (RL) occur according to the literature.
Flora: Malococarpus crithmifolius and Euphortia sclerocyathium are included in the National Red Book.
Pressure/threats to key biodiversity
Drilling people from Shahpahty visit the depression to collect water from the wells.
Conservation responses/actions for key biodiversity
A zoological description of the depression was prepared by K.R. Rustamov and E.K. Rustamov. Observations have also been made by staff of the Nukus antiplague station. In general zoologists very rarely visit this region.
Work on saiga breeding productivity on the Ustyurt have been carried out for 5 years under the INTAS project “The reproductive ecology of saiga”.
There are no Protected Areas.
Habitat and land use
Research drilling activities on the availability of minerals were carried out on the bottom of the depression in the past. Now all drilling is suspended.
BirdLife International (2019) Important Bird Areas factsheet: Northern part of the Assake-Audan depression. Downloaded from
http://www.birdlife.org on 19/09/2019.