CTHOMAS.CASSIN@BIONET-20.BIO.NET (Richard Cassin) (04/18/89)
Posted: Sat, Apr 15, 1989 7:39 PM EDT Msg: LGIJ-3925-6238 From: T.ROYER To: OCEAN Subj: EXXON SPILL REPORTS 4 AND 5 14 April 1989 As you might have seen on the news, the cleanup of the shores of Prince William Sound has begun. Meanwhile the major part of the slick is progressing along the coast of the Gulf of Alaska though Prince William Sound will continue to "bleed" for some time to come. The thought still persists that when oil leaves the sound everything will be fine. However, first reports of mousse off Kodiak Island have been received. These reports combined with the comments by Paul Boehm in SCIENCE (7 April 1989, p. 23) to the effect that after the 1976 Argo Merchant spill off Massachusetts, oil was detectable in the water column for up to 5 months after the spill causes concern for the fisheries off Kodiak. This shelf on the eastern side of Kodiak Island is about 40 miles wide and it is here that the Alaska Coastal Current loses it driving mechanisms of freshwater discharge and prevailing winds. As a result, the residence time on this shelf is 1-2 months. It is close to the spawning time for king crab, shrimp and pollock. The big questions are what are the concentrations of toxic components from the oil within the water column and are the sensitivities of the biological communities. Hydrocarbon sampling of this shelf will take place over the next two weeks and again next month, if necessary. I believe that the oil in the water column on the eastern Kodiak shelf will eventually be entrained into the Alaska Current and carried southwestward into the deep ocean. 15 April 1989 There are now reports of oil ashore on Kodiak Island, in Cook Inlet and at Katmai National Park on the western shore of Shelikof Strait which bounds Kodiak Island to the west. This is consistent with the alongshore transport of the spill by the Alaska Coastal Current with speeds up to about 25 cm/s (0.5 kt) this time of year. A guardedly positive report of the Alpha Helix cruise was made by Peter McRoy (chief scientist) and other participants. The coastal circulation is doing its job! The waters of Prince William Sound show little evidence of the spill with the exception of a few locations such as Snug Harbor that is filled with oil. In general, not as much oil was found as was assumed prior to the cruise. We only see the worst shores on the news. 44 hydrographic stations were occupied with 25 bottom grabs taken and several beaches surveyed. Chlorophyll levels indicate that the spring bloom is underway and the usual sequence of spring events is occurring however the rates are unknown. Only 12 oiled birds were found which is better than the best case scenario. Spring migration has not yet taken place. Superficially, the water column is does not show obvious signs of the oil spill but it should be remembered that the currents are carrying the oil out of the sound and renewing the water with inflow through Hinchinbrook Entrance. Still, some shores are a real mess. Oiled and nonoiled comparisons will have to be made everywhere along the coast from Prince William Sound to beyond Kodiak Island. -------