Fish Biozonation in the Balkan Peninsula, Especially in Bulgaria: A Challenge

Fish are important elements of aquatic ecosystems. Their communities naturally follow the river continuum and have been well described in western European freshwater watersheds. In regions higher endemism, such as Balkan Peninsula, widely accepted fish zonation Illies is doubtfully relevant. this study, a more suitable categorization lotic lentic ecosystems Bulgaria proposed, based on 389 multimethodological multihabitat sampling occasions. Referent-type determined for 33 types recognized water bodies. Adapted rough estimation real distribution assemblances country; moreover, sensitive and/or endemic species generally restricted abundance. view ecosystems, they can be divided into salmonid cyprinid, at approximately 1500 m above sea level.