Unknown Denizens of Lake Hirghiz-nuur in Mongolia

Vladimir Yarmoliuk, Valery Nikolayev *
Russian Society of Cryptozoologists

Abstract: Presented and analyzed are results of investigations on the shores of Lake Hirghiz-nuur in Western Mongolia during 4 field seasons (1985,1987,1989,1990) within the framework of the Soviet-Mongol geological expedition. During a total of 24 days several dozen single and multiple large tracks coming from the water were found on the sand and gravel beaches of the lake. Most of them were discovered on the spit Chatsargany-Shugum on the northern shore of the lake. The tracks appeared regularly within the period of the second half of July and the first half of August. Analysis of the shape and size of the tracks, the location and periodicity of their appearance, interviews with local inhabitants, the hydrology and biological resources of the lake suggest that the tracks may belong to large unknown animals living in the lake.


Mongols living in desert regions, such as the Gobi and the Valley of Big Lakes, have tales of unknown animals and mysterious phenomena reflecting real experiences or popular beliefs. Common are stories about large creatures believed to inhabit big saline lakes of these territories. Most travelers take these stories for local legends, and such was our attitude until 1985 when we discovered enigmatic large tracks on the shore of Lake Hirghiz-nuur. Subsequent observation conducted in the summer months of 1987, 1989, and 1990, showed that the tracks appeared regularly in different parts of the littoral.

The discovery of the tracks was first reported by one of the authors (Yarmoliuk, 1989).

Lake Hirghiz-nuur is situated in Western Mongolia, in the Northern part of the Valley of Big Lakes, a major depression of Central Asia. There are several large interconnected lakes in the valley ¾ Airag-nuur, Hara-nuur, Haraus-nuur, and others ¾ all of them relics from the late Pliocene and the early Pleistocene, when a vast Mesozoic body of water covered the whole of the valley (Devyatkin, 1981). The total area of this lake basin was then about 92000 km2 , with a surface 18-20 m higher than at present. By the Quaternary the climate had become more arid, the lake area shrank, splitting the single body of water into a number of separate lakes. Throughout its history the valley has never been affected by mainland glaciation.

Fig.1 Location of Lake Hirghiz-nuur


Lake Hirghiz-nuur is the largest and deepest in the Valley of Big Lakes. It occupies the lower part of the valley in the midst of sand and gravel terraces and hills (up to 1029 m above sea level) cut by dry river-beds. The length of the lake is 75 km, its maximum width 31 km, the length of the shore line being 253 km. The area of the lake by different estimates is from 1360 to 1407 km2, the volume of water being over 66 km3. Hirghiz-nuur is connected by a narrow, 5-kilometers long channel, called Holai, with Airag-nuur, a shallow fresh-water lake, with an area of 143 km2. So far there is only fragmentary data on the depth and bottom structure of Hirghiz-nuur. According to A.Dulmaa (1974), depths of 40-70 m begin at a distance 100-300 m off shore. The bottom is of sand and gravel and in deeper places covered with a light-grey silt.

The area around the lake is a desert with a meager vegetation. The shores of the lake are also barren, made up of sand and gravel maters with outcrops of rock in some places. That is why the area is practically uninhabited, with only several families of cattle-breeders living near rare water-springs and wells.

The northern shore has two narrow spits knifing the body of water, the length of the Eastern spit, called Shugum, is 11 km, of the Western Chatsargany-Shugum, 9 km. It was on the latter spit that the above-mentioned tracks were first discovered.

Results of observations

In 1985 our expedition for the first time conducted geological investigations in the Mongol Altai mountains which border from the west the Valley of Big Lakes. On July 5, as our route lay alongside Hirghiz-nuur, we decided to camp for the night, on the shore of the lake. We chose the western spit (Chatsargany-Shugum) and, having gone 7 km south, camped on the western side of the spit. The shore there was rising from the water in a series of terrace-like shelves. Some shelves revealed Pliocene pebble outcrops, others were formed by the waves of the lake of different force and had slight drifts of deposited material. The beach of the spit, just like the terraces, consisted of tough large-grain sand strewn over with small-size graves

On the beach, about 200 m from the campsite, we spotted heaps of sand which at close range looked like horseshoe-shaped sand mounds. Their height was 0.5-0.7 m, the width from 0.8 to 1.5 m. Each frontal heap locked on the side of the spit a flat scraped-out indentation flanked by low sand barriers which joined the frontal mound. The indentations were from 1 to 2 m across. What intrigued us most was the fact that the tracks came out of the water. It looked like the sand had been flattened out by a giant iron that moved from the water and worked its way up to the second lower terrace where it stopped unable to overcome the obstacle. Large fragments of pebble concretion and sand-stone, scattered here and there on the beach, were absent within these indentations, but were abundantly present in the horseshoe-shaped mounds. There we found pebble concretions weighing up to 25 Kg. The flat tracks were streaked with narrow length-wise furrows, each ending with a piece of rock sunk in the sand. It was obvious that the furrows had been made by the dragging of these rock pieces. Outside the extreme tracks, along the flanking barriers of sand there were round indentations up to half a meter in diameter.



Fig.2 Sketch of a group of tracks on the beach

We inspected two kilometers of the spit in both directions and found out that the tracks were only present in a limited space of the beach about 80 m in length, sometimes reaching the first terrace. There were no single tracks there, they all lay in groups, each group numbering from 4 to 6 tracks, differing in size, touching and covering one another. The pattern of track overlapping showed a certain sequence of track formation, as well as a tendency to form close groupings.


Fig.3 A group of tracks on the beach.


All in all, we observed there four groups of tracks which differed in their state of preservation and, apparently, in the time of existence. Their states of disintegration under the impact of water and wind were different, and one group looked fresh, its frontal mounds and flanking barriers being relatively steep even within reach of the surf.

Naturally, we started thinking about the origin of the tracks. We ruled out a technical origin. Also ruled out were such natural causes as the action of the water and the wind on the beach. The volume of sand and gravel transported to the frontal heap of each track reached approximately 1 m3 and more, while the distance of the mound from the water's edge did not exceed 10-15 m. We do not know natural abiological forces that could act repeatedly like that within such a limited space and time. These considerations restricted the choice of possible clues to a biological origin of the tracks.

This conclusion was strengthened by a powerful roar that resounded from the lake at about 2 o'clock a.m. It resembled the signal of a ship and was heard twice, lasting each time 3-5 seconds. The roar was so strong that it woke up our driver, a very sound sleeper, who wondered what had happened. We concluded that the sound had come from a spot on the lake some 150 m off shore, but we failed to observe anything in the dim light of a hazy moon.

In the morning we visited the yurt of a local inhabitant, living by a water-spring on the northern shore of the lake. Our Mongol colleague, D.Bold, asked the man about the lake and its denizens and was told that the lake is inhabited by large aquatic animals, called "whales" by the locals. Due to superstitious fears, the locals never attempt to take a good look at these animals.

The next visit to the lake occurred in 1987, when from August 15 to 21 several groups of geologists, conducting work in the mountains to the north, camped together on the spit. We had specially invited our colleagues to visit that place for we wished to show the tracks to disinterested observers, hear their opinions and have additional witnesses of the discovered phenomenon. On that occasion we walked to whole length of the spit and found groups of tracks, all of them with the last 1.5 km of the spit.

Along the western gently sloping shore of the spit we observed 8 groups of large tracks, similar to those found in 1985. All of them were sufficiently fresh, washed away only in those parts of the beach which were within reach of small waves. It followed that the tracks had appeared later than the last big storm. In our experience, such storms occur about once a month or a month and a half, so we concluded that the tracks must have originated within the period of July and the first half of August.

Aside from large tracks we also observed smaller ones. They were found on the eastern shore of the spit, usually lying in the wind shade of the dominant western winds. These tracks were not more than half a meter across, and flanking barriers were from 20 to 25 cm high They were concentrated within 70 m of the beach but did not form separate groups like the large tracks of the western shore.

A third visit to the lake was made from July 13 to 21, 1989, and again we camped on the same spit. That time we observed on the Western side only poorly preserved tracks indicated by crescent-shaped heaps of sand, half a meter high, while the eastern side presented many large tracks. The beach in that part of the spit is steeper than on the western side, and all the tracks were situated within a strip of beach 6-8 m wide and 100-120 m long. They presented almost an uninterrupted sequence and revealed several generations of tracks, fresh ones overlapping older tracks. On that occasion we concluded that the formation of tracks was connected with depositions of sand "bulldozed", apparently, from the underwater part of the spit. That followed from the fact that, despite a large volume of material in the frontal heaps and flanking barriers (up to 2 m3 ), the inner parts of the tracks lay at the same level as the rest of the beach and, consequently, the latter could not have been the source of material. Of much interest to us were big furrows left by boulders, weighing from 10 to 20 kg, indicating their forcible transportation from the lake to the shore.

In 1990 we visited the lake twice ¾ first, passing by on July 18 and a second time we stayed on the same spit from August 14 to 18. If the first time we did not observe any tracks then on a second visit that year we discovered them on the eastern shore of the spit. Thus, for the first time we were able to date the tracks more or less accurately. Indirect data allowed us further to narrow that interval. We found three groups of tracks. The largest of them extended for 17 along the shore with a range of 7 m between frontal mounds and the water's edge. We distinguished two zones of the beach acted upon by the waves not long before. One zone, three meters wide, corresponded to moderate waves, observed on August 12-13 and indicated by damp sand. Within it the tracks were completely washed away. The second zone covered the next two meters of the width of the beach. Within it the tracks were affected but not yet destroyed. Waves that formed that zone deposited algae and fish bones in the tracks.

The summer of 1990 in the area of the lake was rainy and with strong winds. Prom July 18 to August 14 there were several strong storms, washing away old tracks. However, tracks re-appeared in intervals between the storms. Thus, we can judge about the appearance of tracks within, at least, a period of the second half of July and first half of August.

During that visit we inspected the shore almost along the whole littoral. To our surprise, track sites were very few. They were discovered on the tip of the other (11-km-long) spit, as well as in two other points of the southern shore.

Our investigations definitely show that in certain parts of Lake Hirghiz-nuur periodically, from year to year, there appear tracks of a stable morphology and size. They appear in spots of the shore which are rarely visited by people and domestic animals. The time of the tracks appearance is largely midsummer. The evidence suggests their biological origin. They may indicate resting or landing places of large aquatic animals. It can be surmised that these animals are about 8 m long, 1.0-1.5 m wide and weigh several tons. Apparently, their number is low. All these conclusions are drawn from the characteristics of the tracks and the frequency of their appearance.

Naturally, the question arises whether the natural conditions and biological resources of the lake are adequate and sufficient for sustaining such big creatures. To answer this question we cite relevant data.

Some hydrological and biological characteristics of Hirghiz-nuur

The lake's saline water is of a carbonate-sodium type with a mineralization level of 7.23-7.63 g/l, equalling 8.2-9.2 (Dulmaa, 1974). The oxygen content ranges from 8.37 to 10.72 mg/l. Despite cold winters the lake is fully covered with ice only in late December The thickness of ice is 60-70 cm, and from 20 to 40 cm over deeper parts. The lake is freed of ice in April. In summer months the water is warmed in shallow littoral areas to 27-30C.

The lake's bio resources, according to A.Dulmaa(1974), are as follows: phytoplankton is represented by 12 species of algae, mainly Ceratium hirundinella, Gomphosphaeria lacustris, Pediastrum sp. In the littoral zones there are insignificant growths of such algae as Cladophora glmerata, Chara sp., Myriophyllum verticillatum, Potamogeton perfoliatus, and some others. Zooplankton is represented by 10 species, with an average mass of 0.31 g/m3 , characterized by seasonal dynamics.

The lake's ichthyofauna is of a clearly relict nature and represented by one species, Oreoleuciscus potanii Kessler, which has two forms in this water body: one form feeds on plants, the other on fish. Specimens of the latter form reach 100 cm in length and up to 5 kg in weight. An average catch is 32 kg per 100 m of nets. The littoral which makes up about 1/4 of the lake's area, has a productivity of not less than 20 kg per hectar. It is estimated that 7-10 thousand centners of fish could be taken from the lake annually without undermining its fish population's productivity (Dulmaa, 1974). This shows that the fish resources of Hirghiz-nuur are significant and sufficient to sustain large ichthyophagous animals.


Let us note that the Valley of Big Lakes is a closed mainland depression, barred from ocean basins by mountain ridges. The origin of water basins in the valley itself dates back at least to the second half of the Mesozoic. There is less certainty regarding the period of the valley's isolation. In any case, this happened not later than the early Pliocene, when all presently existing mountain structures in Central Asia had already emerged. All of that prompts the conclusion that the tracks described in this article may belong to relict animals whose phylogeny goes back to the depth of the Cainozoic and, perhaps, even earlier times.

The evidence calls for a solid and goal-oriented researching of the lake with the use of special means and modern technology.

* Dr. Vladimir Yarmoliuk, a geologist, is department chief at the Institute of Geology of the Russian Academy of Sciences in Moscow.

Valery Nikolayev is a zoologist, Ph.D. in Biology, assistant professor, scientific deputy director of the Zavidovo preserve, Tver Region, member of the Russian Society of Cryptozoologists. The field-work described in this article was carried out by Dr.Yarmoliuk while the biological analysis of the results has been done by Dr.Nikolayev who plans to participate in future expeditions to lake Hirghiz-nuur.

** The pronoun "we" implies Yarmoliuk and other members of his expedition, not the other author of the article (Translator's note).

References cited

Devyatkin,E.B. 1981 The Cainozoic of Inner Asia (in Russian). Moscow: Nauka.

Dulmaa,A. 1974 Biology of the lakes of the Mongol People's Republic
(doctorate dissertation, in Russian). Irkutsk.

Yarmoliuk, V.V. 1989 Sledy nevidannykh zverey (Tracks of unseen animals). Priroda, No.4:79-81.

February 1992


Translated by Dmitri Bayanov
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