Table 1 Survey methods used for data collection.

Shallow diver transects^32,33

2013, 2015–2021

5–35 (21)

Belt transects (30 m \(\times\) 4 m \(\times\) 4 m, or 480 m³), along depth contours

Relative density (count/480 m³) of fish and structural corals, by species

Percent cover category of large-bodied sponges, aggregated for all Hexactinellidae and Demospongiae

Larger, older rockfishes³⁸ and most structural corals⁶⁵ tend to be deeper than the max. depth of dive surveys. Consistent with earlier publications³³, analyses excluded fish < 10 cm-long. Sponge cover categories: 0 = 0%; 1 = 1- 25%; 2 = 26–50%; 3 = 51–75%; 4 = 76–100%

Mid-depth video transects^32,50,51

2015–2018

15–200

(67)

Belt transects of variable size were divided into bins covering 75–130 m² (mean = 116 m²) to reduce depth and habitat variability within spatial units. (Bins < 75 m² are end cuts and bins > 130 m² reflect GPS data gaps; analyses exclude both.) Parallel laser beams (10-cm apart) provide a distance scale

Relative density (count/m²) of fish and structural corals

Percent cover category of large-bodied sponges, aggregated for all Hexactinellidae and Demospongiae (see dive transects for category values)

Height of coral colony (distance from base to highest branch tip)

Fish counts were corrected for species detection biases (i.e., attraction to laser beams)^50,51. Camera lacks panning/tilting ability and depth capacity of BOOTS camera (see below). The lower bound for bin size in earlier analyses³² was 100 m², which we lowered to 75 m² to not exclude some coral-rich areas. Heights for the coral Calcigorgia spp. were measured from 32 images in which the “flat” aspect of corals was perpendicular to the camera. (Other coral taxa were measured from Deep video)

Deep video transects (BOOTs)³⁵

2018

100–500

(253)

Belt transects varied widely in area but were divided into similar size bins, as described for mid-depth video transects. Parallel laser beams (10-cm apart) provide a distance scale

Relative density (count/m²) for fish, structural corals, and large-bodied sponges

Height of coral colony

Fish counts were corrected for species detection biases^50,51. Coral heights were measured from 20 randomly selected images per taxon in which “flat” aspect of corals was perpendicular to the camera. Transect bins averaged 120 m²

Hook-and-line³⁴

2006–2007; 2013–2015

15–205

(57)

Standardized gear fished the bottom for 15-min or 30-min sampling sessions

Relative density (count/min) for each fish species

During 2006–2007 data were collected by the Heiltsuk Nation prior to CCIRA’s inception