Herring stock estimates from diving surveys of spawn on the west coast of Vancouver Island in 1986 / by C.W. Haegele and J.F. Schweigert. : Fs97-4/1959E-PDF

"Spawn surveys estimated herring stocks on the west coast of Vancouver Island in 1986 at 42,447 tonnes. In Area 23 (Barkley Sound), 26,600 tonnes were estimated to have spawned in a single wave, principally in Loudon Channel. In Area 24, 654 tonnes spawned in Clayoquot Sound and 1761 tonnes spawned in Hesquiat Harbour for an estimated total of 2415 tonnes. There were 8405 tonnes of spawners estimated in Area 25, all of which spawned in Esperanza Inlet and the bulk (93%) spawned in the second of three waves. There was no spawn observed in the Nootka Sound portion of Area 25 and no spawn was recorded in Area 26. In Klaskish Inlet a stock of 815 tonnes was estimated and in Forward Inlet a stock of 4009 tonnes was estimated, for an Area 27 total of 4824 tonnes. Stocks on the west coast of Vancouver Island showed a 50% increase over stocks estimated in a similar survey in 1985. Egg densities were lower in Area 24, at 74,825 eggs per sq. m, than in any of the other areas, where it ranged from 458,464 to 521,761 eggs per sq. m. Spawn was deposited deeper in Barkley Sound, where over 50% of the spawn was deposited lower than 6 m below chart datum, than in the other areas, where no eggs were deposited deeper than 6 m below chart datum. Sea grasses were the most common vegetation utilized for egg deposition in shallow water while filamentous red algae were the most common vegetation in deeper water. Approximately 3% of the eggs were deposited on the giant kelp, Macrocystis sp."--Abstract, page iii.

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