Abstract

Blood volumes, hemoglobin concentrations, packed-cell volumes, and heart weights were determined in three genera of porpoises which differ from one another in behavior and ecology. The estimate for the total blood-oxygen content of the highly active, deep-diving, pelagic species Phocoenoides dalli was almost three times greater than that for the coastal-dwelling species Tursiops truncatus, and about 70 percent greater than for the less active pelagic species, Lagenorhynchus obliquidens. Heart weights of Phocoenoides dalli were about 140 percent greater than in Tursiops truncatus and 55 percent greater than in Lagenorhynchus obliquidens.