Herring stock estimates from diving surveys of spawn for the west coast of Vancouver Island in 1985 / by C.W. Haegele and J.F. Schweigert. : Fs97-4/1922E-PDF

"Using the results of diving surveys of spawn we estimated that 28,311 tonnes of herring spawned on the west coast of Vancouver Island in 1985. In Area 23 (Barkley Sound) 15,288 tonnes spawned, of which 12,647 tonnes spawned in a first wave and 2641 tonnes spawned in a second wave. Most of the herring in Barkley Sound (13,463 tonnes) spawned in Loudon Channel, the remainder spawned in Trevor Channel. In Area 24, 6253 tonnes spawned in Clayoquot Sound and 3870 tonnes spawned in Hesquiat Harbour for a total of 10,123 tonnes. There were 1121 tonnes of spawners in Area 25: 6 tonnes spawned in Nootka Sound, and 811 tonnes spawned in a first wave and 304 tonnes in a second wave in Esperanza Inlet. No spawn was observed in Area 26. In Klaskish Inlet in Area 27, 1320 tonnes spawned in three waves; 29 tonnes in the early spawn, 860 tonnes in the middle spawn which was not surveyed, and 431 tonnes in the last spawn. In Forward Inlet in Area 27 a spawning stock of 459 tonnes was estimated. Of this, 226 tonnes were used by the spawn-on-kelp operation, which harvested 14.5 tonnes of product and had the eggs from 81 tonnes remaining at the pond sites after harvest. Spawning stocks were 35% higher in Area 23 and 24 and 34% lower in Area 25 in 1985 than in 1984. The distribution of spawn by depth was documented, and, except for first wave spawns in Barkley Sound, most spawn was deposited shallower than 3 m below chart datum"--Abstract, page iv.

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