Shoreline vegetation on herring spawning grounds between Deep Bay and Dorcas Point, Strait of Georgia, B.C. / by C.W. Haegele. : Fs97-4/1485E-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 the shoreline between Deep Bay and Dorcas Point on April 7, 1977. Vegetation maps were prepared from these using colour and texture keys previously developed. Subsequently, between March 5 and April 11, 1978, a diver survey of herring spawnings in the study area was used to evaluate the accuracy of the photo-mapped vegetation. Divers collected 418 samples on 62 diving transects. Vegetation was identified on aerial photographs for 72% of these samples. For samples taken on herring spawn transects, vegetation was identified for 80% of samples. Vegetation not identified on photographs was always in deeper water and of low percent cover. There were 103 species of algae and sea grasses collected. The vegetation is commonly up to 600 m wide and the total area of vegetation identified from photographs is 6.2 x 10⁶ m² along 60 km of coastline"--Abstract, page iii.

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