Shoreline vegetation on herring spawning grounds in Clayoquot Sound / by C.W. Haegele and M.J. Hamey. : Fs97-4/1536E-PDF

"The ability to accurately record and assess herring spawnings depends to a considerable degree on a knowledge of the vegetative substrate upon which the adhesive eggs are deposited. Large format colour and colour-infrared photographs were obtained for 87 km of shoreline in Clayoquot Sound on June 26, 1978. Vegetation maps were prepared from these using colour and texture keys previously developed. There were 1561 ha of vegetation mapped with sea grasses accounting for 55%, the remainder being associations of red and brown algae. A diver survey of herring spawnings in March 1979 was used to field check the vegetation mapping. The presence of vegetation was identified on aerial photographs for 99% of samples collected by divers along transects and correctly typed for 95% of samples. Sand was the predominant bottom type. The middle two-thirds of the samples were collected between -0.6 and -2.5 m. The percent cover of vegetation was also highest at this depth range at 56(±4), while it was 53(±9) above -0.6m and 34(±5) below -2.5m"--Abstract, page iii.

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