Observations of Free-Swimming Porpoises and Whale Schools and Studies of the Chemistry of Head Oil in Porpoises.

In March, 1971, a cruise on board the Hiki No was taken for the dual purpose of obtaining acoustic information and attempting to track a porpoise by radiotelemetry. The record validated the idea that the porpoise school moved offshore a rather short distance, a maximum of four miles, and fed over the region in which the subsurface pediment of the island drops abruptly into deep water. Once in this region the school simply continued to move back and forth diving for periods averaging about four minutes below the surface on each descent. An effort to record and describe the sound emissions of the spinner porpoise was begun. Good recordings are being obtained using a Uher recorder, an LC34 hydrophone, cables, pre amp, and a complete set of analyzing gear. It is too early to describe the sounds since they are now being analyzed. The finding of large amounts of isovaleric acid and long-chain iso acids in porpoise head tissues illicited an interest in the molecular structure of triacylglycerols, the main lipid fraction. Knowledge of the isomeric structure of triacylglycerols should contribute to a clearer understanding of the role of L-leucine and isovaleric acid in the biosynthesis of lipids of adipose tissue. Porcine pancreatic lipase hydrolysis, followed by chromatography of the reaction products, leads to the isolation of a highly branched fraction of triacylglycerols containing an average of two moles of isovaleric acid and a high proportion of isopentadecanoic acid.