Water movements and the distribution of Hydromedusae in British and adjacent waters

Abstract

The waters around the British Isles and the North Sea are rich in species of Hydromedusae, particularly Anthomedusae and Leptomedusae. They are valuable as biological indicators of hydrographic conditions, especially movements of water-masses. A general account is given of the non-tidal circulation in the region. The distributions of selected species of medusae are described and discussed in relation to water movements. Because of its hydrographic complexity, the meteorological conditions and the varied nature of the sea-bottom, the region has a rich medusa fauna with diverse zoogeographical elements.