Reed marshes bordering the coast of the North-West Precaspian plain are undergoing a profound transformation due to fluctuations in the level of the Caspian Sea. Indicator of the marshes is their projective cover, determined by satellite images. It was found that compared with 1978 to 2010 the square area of reed beds with maximal cover decreased, while the area of reed beds with minimal cover increased. Refs 2. Figs 4. Table 1.