Derryvree’s Waterlogged Tundra
Archived: 16 September 2026
Although 31,539 BCE is a modern conversion rather than a precise Irish date, Derryvree, County Fermanagh, illuminates later Marine Isotope Stage 3. Organic freshwater sediments, dated broadly to 36,900–31,700 calibrated BP, formed between glacial advances, demonstrating local ice-free conditions. Their plants, pollen and insects depict a cold, treeless, waterlogged tundra of sedges, grasses, mosses, juniper and herbs. Ireland's environments and ice margins varied regionally before the Last Glacial Maximum. Castlepook Cave preserves diverse cold-stage fauna, including mammoth, reindeer and hyena, plus a possible butchery-marked reindeer bone. This suggests brief human visits, not established settlement, amid later glacial destruction of evidence.