Subterranean Fishes of the World

308

1989

Proceedings of the 10th International Congress of Speleology, Budapest

679

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Kugitang-Tau caves is a unique place on the territory of the USSR, where eyeless troglobiontic loach (Nemachilus starostini) live. Underground lakes are formed in gipsum rocks . The concentration of gipsum in water of these lakes is about 3.5 g/l. Caves are investigated to the depth of 58 m. The maximum depth of subaquatic caves in this region is not determined. In the axpedi tione from 1981 till 1985 the maill numbers of loachea were found 1n the nearest part of the underground lake. Observations have shown• that fishes consume the bacterial films on the surface of organic silt, which 1a accumulates under the bird and bat nests. The depth of the lake 1n this place is not more then 4-5 m. lligratione of loachee during the day waa regietrad, llaJd.mum numbers of fishes was marked on the shallow part of the lake at night. Some 1ndiv:l.dual loachee were registred on the depth of 20-25 m, But in tha llay 1986, after tha strong rain, stratification of bottom ail t was affected and loachea were scattered all over the subaquatic cave up to the depth of 58 m. No changes of fishes activ:l.ty ware regietred during the day. Thus, distribution of troglobiontic loaches daa not depend on the depth, but depends only on the distribution of organic material.

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