258 
Fishery Bulletin 113(3) 
57°50'N 
57°40'N 
152°40'W 152°20'W 
Figure 1 
Map of locations of the 4 study sites around the eastern end of Kodiak 
Island, Alaska, where scrape tows and beam trawl hauls were conducted 
from May through August in 2010 and 2011 to examine the depth distri- 
bution, habitat association, and growth of newly settled southern Tanner 
crab (Chionoecetes bairdi). Inset shows location of Kodiak Island in rela- 
tion to the Gulf of Alaska and Bering Sea, 
Scrape estimation of crab density 
Crab densities were estimated from sampling conduct- 
ed with a video camera sled (Spencer et al., 2005; Ston- 
er et al., 2007; Ryer et al., 2013). Hereafter referred to 
as a “scrape,” the sled was augmented with a cutter bar 
and a codend that was 3 m long and had a 3-mm seine 
mesh. The tubular aluminum frame measured 114 cm 
long by 67 cm wide by 42 cm high. An aluminum cutter 
bar (width: 5 cm, thickness: 0.5 cm), mounted across 
the rear of the scrape between the runners and at an 
angle of 45°, scraped off the upper 2-3 cm of the sedi- 
ment surface as the scrape was towed along the bot- 
tom of the seafloor. Fastened to the rear of the scrape 
and immediately behind the cutter bar, the codend had 
a lead line attached along its leading edge, to main- 
tain contact with the bottom. Sediment displaced by 
the cutter bar passed over the lead line and into the 
codend. A video camera positioned just forward of the 
codend, at the top of the scrape, provided an oblique 
view of the bottom traversed. The video images were 
transmitted by a cable to the vessel and were recorded. 
Scrape tows were made parallel to shore at depths 
ranging from 3 to 25 m, at a speed of 0.5 m/s for ~30 
m. The actual distance towed was determined with the 
GPS coordinates of the start and end of each tow. On 
deck, the codend was briefly rinsed with seawater to 
remove any remaining sediment, and the contents were 
deposited into a plastic tray, sorted, and all Tanner 
crabs were enumerated. During 2010, 121 tows were 
made at Holiday (May: 30, June: 32, July: 29, August: 
30) and 168 were completed at Pillar (May: 48, June: 
47, July: 36, August: 37). In a more limited effort, we 
made 23 tows at Womens (July: 4, August: 19) and 4 
tows at Kalsin (August: 4). During 2011, 111 tows were 
made at Holiday (May: 26, June: 35, July: 30, August: 
20), 89 were conducted at Pillar (May: 23, June: 26, 
July: 20, August: 20), 132 at Womens (May: 13, June: 
34, July: 42, August: 43), and 105 were completed at 
Kalsin (May: 25, June: 30, July: 30, August: 20). Dur- 
