Crabs of the British Isles (29,193 t), various swimming crabs (3,180 t), the spider crab "Maja squinado" (1,565 t), the shore crab or green crab "Carcinus maenas" (553 t) and the velvet crab "Necora puber" (193 t). Around 77% of the catch is landed in the United Kingdom, 19% in Ireland, 4% in the Channel Islands, and 1% in the Isle of Man. 62 species have been directly observed in the waters of the British Isles: Three deep-water species have also been recorded near the British Isles, and are likely to occur in the area. These are: Crabs of the British Isles Around 65 species
Climate of the British Isles drought of 1975–1976 and the very cold winters of 1946–1947, 1962–1963, 1978–79, 1981–1982 and 2009–2010, are often caused by blocking anti-cyclones which can persist several days or even weeks. In winter they can bring long periods of cold dry weather and in summer long periods of hot dry weather. Tropical cyclones themselves do not affect the British Isles due to the cold temperature of the surrounding ocean. Any tropical cyclone that comes near the Isles has said to have undergone a process called extratropical transition. The Isles do experience these extratropical cyclones, the Great Storm of 1987 was a deep