Observations of natural and man-made floating megalitter, macrolitter and mesolitter in the Pacific section of the Southern Ocean Whale Sanctuary from December 1994 to March 1995 are reported. Natural megalitter, mostly seaweed, was concentrated In the more northern latitudes near the start and finish of the expedition, especially near the Antarctic Convergence south of the Tasman Sea. Man-made megalitter was nowhere common, but was seen mostly near and to the west of the Antarctic Peninsula, and north and northwest of the Ross Sea, and consisted mostly of plastic Items, especially styrofoam fragments. Fishing gear was not a major component of man-made debris. Macrolitter consisted mainly of seabird feathers. A very high density (544 per 10nm) of penguin feathers occurred northeast of the Ross Sea, whereas non-penguin feathers dominated north and northwest of the Ross Sea. In the southern Ross Sea a single sample contained 31 small dead fish. Natural mesolitter quantities were usually low, but high densities (to 391/ha) of penguin feathers occurred northeast of the Ross Sea, and pumice granules were concentrated near the Antarctic Convergence south of the Tasman Sea. Man-made mesolitter was usually absent but reached 8.7/ha midway between the Antarctic Peninsula and the Ross Sea. Most items were individual styrofoam beads, but north of the convergence small numbers of hard plastic fragments were encountered. Biological associations with debris were not common, but included a filamentous green alga and small goose barnacles.
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