Politics in the British Isles Politics in the British Isles The British Isles comprise two sovereign states, Republic of Ireland and the United Kingdom, and three dependencies of the British Crown, Guernsey, Jersey and the Isle of Man. Ireland is a unitary state and a republic. Since 1998, it shares certain common institutions with Northern Ireland, in the United Kingdom, from which it was partitioned in 1921. The United Kingdom is a constitutional monarchy and also a unitary state comprising England, Scotland, Wales, and Northern Ireland. Also since 1998, the United Kingdom has devolved significant domestic powers (though differing in extent) to administrations in Northern
Introduced species of the British Isles are susceptible. The grey squirrel is a carrier of the squirrel pox virus which kills red squirrels but not grey squirrels. The European crayfish is susceptible to crayfish plague which is spread by the introduced signal crayfish. Unlike some other environmental problems such as pollution, the effect of an introduced species is not a single event. Once a species has been introduced to an island, the problems may persist and escalate as the species spreads further. Coypus "(Myocastor coypus)", large semi-aquatic rodents native to South America, were introduced to the British Isles in 1929 when fur farms were set up