History of the North Sea great herring fishing industry resulting in Scotland becoming a European leader in that industry. During the First Schleswig War (1848–51), the Crimean War (1854–56) and the Second Schleswig War (1864), belligerents took steps to reduce or eliminate commerce in the North Sea by their enemies. In the first Schleswig War, Denmark was able to halt maritime commerce by Germany in the North Sea and in the second, imposed tolls on ships crossing through the Danish straits between the Baltic and North Seas. The Crimean War saw British and French expeditions sent into the Baltic to prevent Russian ships' egress into
Fish species of the Neretva basin Fish species of the Neretva basin The fish fauna of the Neretva river basin in the western Balkans is representative of the Dinaric karst region and characterized by several endemic and endangered species. Overall the Dinaric karst water systems support 25% of the total of 546 fish species in Europe. The river Neretva and its tributaries represent the main drainage system in the east Adriatic watershed and the foremost ichthyofaunal habitat of the region. The Adriatic basin has 88 species of fish, of which 44 are Mediterranean endemic species, and 41 are Adriatic endemic species. More than half of the