LIMNOCYTHERIDAE AND CANDONIDAE OSTRACODE PALEOECOLOGY OF LOUGH CORRIB, WESTERN IRELAND: A HOLOCENE NORTH ATLANTIC CLIMATE RECORD

Holocene climate events observed in marine sediment and Greenland ice cores have recently been demonstrated to correlate with some continental lake sequences. Such lacustrine records can fill the considerable gap in paleoclimate information for continental regions if detailed reconstructions can be generated. Lough Corrib, in Western Ireland is ideally situated in a climatically sensitive region near the center of the North Atlantic Oscillation. Ostracods were recovered from two 5-8 m sediment cores to reconstruct and constrain the paleoecologic and paleoclimatic history of the Holocene in western Ireland. The primary taxa include Candona candida, Candona sp., Paracandona euplectella, Metacypris cordata, Cyclocypris ovum, and Limnocytherina sanctipatricii. Census counts of the ostracode populations record a long term paleoecologic biofacies change from an oligotrophic late Holocene glacial lake dominated by L. sanctipatricii to a progressively eutrophic mid-to Late Holocene marl lake/peat bog marked by increased dominance by Metacypris cordata. Higher frequency alternations between the Limnocytheridae and Candonidae record centennial and/or decadal climatic oscillations established in the North Atlantic.