Mass disease and mortality of Baikal sponges

Abstract

In recent years, signifcant changes in the ecological system of the coastal (littoral) zone, including mass death of the endemic representatives of the freshwater sponges of the Lubomirskiidae family, have been an urgent problem of Lake Baikal. Similar problems are known all over the world. Thus, mass disease and death of corals and sponges are indicated in the Mediterranean, Adriatic, Caribbean and other seas, which raises serious concerns about the future of these biocenoses (Olson et al., 2006; Webster, 2007; Wulff et al., 2007; Stabili et al., 2012). In Baikal, diseased sponges were frst found in 2011. The area of sponge disease is constantly expanding, and, to date, dying specimens have been found throughout the lake. The mass death of sponges occur in presence of the large-scale violation of the spatial distribution and the structure of phytocenoses in the littoral zone, but the causes of these phenomena are unknown. The relevance of the problem arises from the fact that changes in the littoral zone of Lake Baikal can signifcantly affect the productivity and composition of planktonic organisms and zoobenthos, which are the food base for fsh, as well as the quality of drinking water. The deterioration of the ecological state also affects the attractiveness of the lake for tourism. At the international level, serious intellectual and fnancial resources were mobilized to solve similar problems. Despite the obvious relevance, in Russia such studies are carried out irregularly by small groups of researchers.