FISHERY BULLETIN; VOL. 87, NO. 1 



MATERIALS AND METHODS 



Study Sites 



Study sites were located in Barkley Sound on the 

 west coast of Vancouver Island (Fig. 1). Sublegal 

 size northern abalone were removed from 5 km of 

 exposed shoreline at the entrance to Barkley Sound 

 (source area), and these abalone were transplanted 

 to site A on Fleming Island and site B on Tzartus 

 Island, 10-12 km towards the head of Barkley Sound 

 from the source area. For the purposes of this study, 

 sublegal size northern abalone are defined as 50-99 

 mm in length. These individuals should recruit to 

 the fishery within 0-3 years, given suitable habitat. 



An exposed rocky pinnacle (site C) within the 

 source area was designated as a control site to 

 measure growth and recovery of nontransplanted 

 northern abalone. The three study sites were iso- 

 lated by natural features (e.g., sand) from nearby 

 abalone habitat to minimize immigration or emigra- 

 tion. 



The source area consisted of a series of rocky 

 headlands and bays. The habitat of the headlands 

 and control site was typical of exposed rocky out- 

 crops on the west coast of Vancouver Island. At the 

 control site, a 2 m band of vegetation {Lessoniopsis 

 littoralis and Laminaria groenlandica) formed the 

 lower intertidal zone, and northern abalone and sea 

 urchins, Strongylocentrotiisfranciscamis, occurred 



below this zone on a rocky reef dominated by en- 

 crusting coralline algae. Bays in the source area 

 were sloped less steeply and contained beds of 

 Nereocystis luetkeana and Pterygophora califomica. 

 Transplanted northern abalone were collected from 

 both headland and bay habitats in the source area. 



Both transplant sites were located in and direct- 

 ly below beds of Macrocystis integrifolia situated 

 on isolated rocky reefs. Sites were defined by mark- 

 ing 60 m wide x 8 m deep sections of these beds 

 with a weighted line at each lateral boundary. The 

 Macrocystis bed at site A was 2-5 m wide, bordered 

 by a deeper 3 m wide band of brown algae, Des- 

 marestia ligulata. The substrate at this site was 

 steeply sloped bedrock. Large boulders, covered by 

 P. califomica and encrusting coralline algae, oc- 

 curred at the base of the bedrock slope. Sea urchins 

 (S. frandscanus and S. purpuratus) occurred below 

 the vegetation zone to a depth of 8 m. At deeper 

 depths the bottom was composed of sand, isolated 

 cobbles, and boulders. 



At site B, the Macrocystis zone was 6-8 m wide 

 and bounded at the lower edge by kelps (Laminaria 

 satcharina, P. califomica, and Agarum fimbria- 

 tum). Desmarestia ligulata, although present, did 

 not form a distinct zone as at site A. The bedrock 

 substrate was sloped less steeply than at site A and 

 was overlain with loose cobbles. At deeper depths, 

 sand was the primary substrate. As at site A, sea 

 urchins were present below the vegetation zone. 



Figure 1.— Location of the study sites in Barkley Sound on the west coast of Vancouver Island. 



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