Vistula Lagoon million. However, major ecological considerations stand in the way. For example, mammal migration along the lagoon could be disrupted. Also, the inflow of brackish waters from the Baltic sea could result in serious unbalancing of the lagoon's freshwater ecosystem. From 1772 until 1918, the lagoon was part of the Kingdom of Prussia, which had become part of the German Empire in 1871. Between 1920 and 1946 it was split between Germany and the Free City of Danzig. At present state since 1945 its eastern part belongs to Russia (formerly USSR), Poland has 43.8% of its area at lagoon's western side.
Muthupet Lagoon mangrove forest is divided into Palanjur reserve forest, Thamarankottai reserve forest, Maravakkadu reserve forest, Vadakadu reserve forest, Thuraikadu reserve forest and Muthupet reserve forest. The word 'lagoon' refers to the shallow salt or brackish water body that lies close to the sea. Muthupet reserve forest covers the lagoon, river creeks and the mudflats. Muthupet (mullipallam) Lagoon is a spectacular natural creation, which is 8 km from nearby Muthupet town and can be reachable only by boat. The lagoon is shallow with the average of 1m depth. The bottom of the lagoon is formed of silt clay substratum. The tidal fluctuations