A Reindeer Bone at Castlepook
Archived: 20 September 2026
31,011 BCE is a modern label within the fluctuating late Marine Isotope Stage 3, not a precisely datable Irish event. Ireland was approaching major British-Irish Ice Sheet expansion, yet some areas retained open, cold ecosystems. Derryvree, County Fermanagh, preserves evidence of treeless wetlands, tundra plants and freshwater habitats before glacial overriding. Castlepook Cave, County Cork, yielded diverse fauna, including reindeer, mammoth, hyaena and Arctic fox, indicating periodically viable habitats. A reindeer femur, dated about 33,000 years ago, may bear butchery marks, suggesting possible human presence. However, it proves neither settlement nor continuous occupation; ice later destroyed or buried much evidence.