The change in abundance of temperate water Globorotalia inflata relative to changes in populations of Globorotalia truncatulinoides (both coiling directions) and Neogloboquadrina pachyderma was used to determine the ecostratigraphic biozonation of DSDP Site 606 in the mid-Atlantic Ocean. Fluctuations between cold and warm water planktonic foraminiferal forms were interpreted to represent paleoclimate change that occurred with the onset of glaciation. Correlation of these climatically controlled biozones with other datums (traditional biostratigraphic, magnetostratigraphic and oxygen isotope) was utilized to improve the regional chronology for the mid-Atlantic Ocean. Polytopic vector analysis and percent calcium carbonate analysis were utilized to determine controls affecting faunal distribution across Site 606. Shifts in water masses, changes in salinity and temperature, and shifting of the Gulf Stream were all found to be factors controlling the distribution of planktonic foraminifera at this site. Changes in the percent calcium carbonate content were found to reflect glacial/interglacial oxygen isotope stages and were therefore used as proxy indicators for paleoclimate change. Whole core magnetic susceptibility data were utilized to determine transition periods between glacial/interglacial stages. Peaks in materials bearing magnetic signatures were found to correspond to changes in the paleoclimate and indicate an influx of ice rafted material to Site 606 initiated by melting of the North Atlantic ice sheet.