Nidjili lake: Lena River Basin (Russia)

Abstract

Nidjili Lake is the largest lake (catchment area of 1,010 km2, a surface area of 119 km2) in the Lena River basin. It is located in the northern Lena-Vilyuy interfluve (63°35'N, 125°90'E). The lake is believed to have formed in the late Pleistocene as a result of erosion and thermokarst processes. The maximum Lena basin values of benthos biomass and density were recorded for the dominating substratum. At least since the 1930s, the lake has experienced an intense natural eutrophication process accompanied by alterations in hydrochemical properties and corresponding simplification in fish species composition. Up to the late 1950s, the lake played a significant role in sustaining populations of common goldeneye and white-winged scoter, which nested and molted in the tens of thousands of individuals. No other area of such a small size was known in northeastern Asia to support such large accumulations of molting goldeneye. High fish productivity resulted in a high nesting density of osprey, white-tailed eagle, ducks, waders, gulls, and terns. The processes of significant anthropogenic technological transformations are absent. The lake and its catchment area have not endured any man-made habitat changes and are still capable of sustaining the same significant numbers of water birds that occurred here in the mid-twentieth century if hunting (poaching), boating, and summer fishing are controlled, allowing the bird population to recover.