. The Canadian field-naturalist. Natural history; Sciences naturelles. 364 The Canadian Field-Naturalist Vol. 120 Cumulative Abundance; Depth 10m Cumulative Abundance: Depth 50m U^_ 1 I ,---1 1 1 tl^,*^-^ J Species. Species Figure 1. Cumulative species abundances of scavengers observed at carrion anchored at 10 m and 50 m in Barkley Sound, Vancouver Island. were the dominant species, while at 50 m. Long-rayed Star {Stylasterias forriei) (20-60 cm), Spot Shrimp (Pandalus platyceros) (12-20 cm), Spotted Ratfish (Hydrolagus colliei) (18-25 cm), Pacific Hagfish (35- 65 cm) and Rocksole (Lepidosett
. The Canadian field-naturalist. Natural history; Sciences naturelles. 364 The Canadian Field-Naturalist Vol. 120 Cumulative Abundance; Depth 10m Cumulative Abundance: Depth 50m U^_ 1 I ,---1 1 1 tl^,*^-^ J Species. Species Figure 1. Cumulative species abundances of scavengers observed at carrion anchored at 10 m and 50 m in Barkley Sound, Vancouver Island. were the dominant species, while at 50 m. Long-rayed Star {Stylasterias forriei) (20-60 cm), Spot Shrimp (Pandalus platyceros) (12-20 cm), Spotted Ratfish (Hydrolagus colliei) (18-25 cm), Pacific Hagfish (35- 65 cm) and Rocksole (Lepidosetta bilineata) were dominant. Only two of 16 species (Spotted Ratfish, Kelp Greenling) were common to both sites (Figure 2). Although all species were in direct contact or imme- diately adjacent to the carrion, only six species active- ly foraged off the carrion (Pacific Hagfish, Redrock Crab, Dungeness Crab {Cancer magister). Sunflower Star (Pycnopodia helianthoides). Long-rayed Star {Orthasterias koehleri), and Spot Shrimp). Hagfish undertook extensive burrowing and excavations and were the major consumers of tissues. Ratfish swam commonly in close vicinity to the carrion but we observed no foraging activity. Daily consumption rates at 10 m were initially high and then decreased while at the 50 m site, the rate increased throughout the duration of sampling. On the last ROV survey (Day 23), 40% of the soft tissues remained at the 10 m site while only bone remained at the 50 m site. Diel variations The scavenger community differed during daylight and darkness (Figure 3). At both sites there were in- creased numbers of species observed during darkness (10 m Day, 5 , Night, 11; 50 m Day, 5, Night, 9). At 10 m depth, nocturnal scavengers were Redrock Crab, Spotted Ratfish, Roughback Sculpin {Chitonotus pugetensis), and Dungeness Crab. At 50 m. Long rayed Star was present in both day and night trials and was seen continually in all surveys. Northern Ronquil {Ron- quilus jordani), Roc
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