Herring spawning stock biomass estimates from diving surveys for the central coast in 1986 / by J.F. Schweigert and C.W. Haegele. : Fs97-4/1984E-PDF

"Diving and surface spawn surveys in 1986 indicated that 25,946 tonnes of herring spawned in the Central Coast District (Statistical Areas 6-9). In addition, roe seine fisheries in Area 7 caught 1707 tonnes and the roe gillnet fisheries in Areas 6 and 7 caught 1084 tonnes of herring. The food and bait fisheries in Area 8 caught another 30 tonnes of fish. Most of the spawning occurred in Area 7. Over half (57%) of the spawn occurred in this area, where 72 km of spawn was deposited by 14,703 tonnes of herring. In Area 6 38.7 km of spawn was deposited by 7168 tonnes (28%) of fish. Area 8 spawn deposition totalled 15.7 km and 2844 tonnes (11%). Finally, the spawn at the head of Rivers Inlet (Area 9) totalled 16.3 km and 1231 tonnes of herring or 5 % of the total Central Coast deposition. The 1986 diving survey was the first conducted in the Central Coast and results indicated that spawn distribution was similar to that in other Districts. Spawn was confined primarily to the intertidal and upper subtidal zone (above 3 m below chart datum). The percent cover of vegetation and the sample weights were also similar to those in other Districts and declined with depth only in the lower subtidal zone (deeper than 3 m below chart datum). Egg layers and egg density followed a similar pattern. However, the slopes of the beaches were much steeper than for other spawn surveyed to date. In addition, the vegetation types utilized for spawning differed from other Districts, consisting primarily of kelps, rockweeds and filamentous red algae"--Abstract, page iii.

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