Castlepook’s MIS 3 Fauna
Ireland stood within the last Ice Age, but it should not be imagined as a simple, permanently frozen island under one unchanging sheet of ice. MIS 3 was climatically unstable, and the growth, extent and behaviour of the British–Irish Ice Sheet varied regionally and through time. Research on southern Ireland indicates that the main expansion of the last Irish ice sheet began from initially ice-free conditions at about 34,000 years ago and reached the south coast only after about 24,000 years ago. Around this notional date, then, parts of Ireland may have remained available to cold-adapted animals even as glacial conditions intensified elsewhere. That is an interpretation from regional geological evidence, not a precise map of conditions on any one day or in every valley.