Groundfish Longline Survey Data for Northern British Columbia Coast

Fishery-independent catch, effort, location, and biological data from multi-species longline surveys on the northern British Columbia coast. The Outside North Hard Bottom Longline survey series began in 2006 and is conducted biennially, covering the mainland coast north of Milbanke Sound and the Haida Gwaii region. Data is collected by Fisheries and Oceans Canada in collaboration with the Pacific Halibut Management Association using chartered commercial vessels.

Use Cases

• Analyze catch counts by species relative to fishing location (latitude and longitude) and depth to map species distribution.
• Model species abundance indices using effort data including soak time, hook spacing, and number of hooks counted per set.
• Examine biological data such as length, sex, weight, and age for sampled catches to study population demographics.
• Relate trip-level information like vessel, year, and trip dates to set-level catch data using the unique trip and set identifiers.

Strengths

• Data originates from a long-term, coordinated survey series with a consistent methodology using size 14/0 circle hooks baited with squid.
• Surveys follow a random depth-stratified design within 2 km by 2 km sampling blocks, providing structured spatial coverage.
• The survey series provides fishery-independent data specifically for assessing species in untrawlable, hard-bottom habitats.

Limitations

• The dataset excludes inlets and protected waters east of Vancouver Island, limiting geographic coverage of the broader region.
• Catch data is recorded as counts only, lacking weight measurements for individual catches in the catch table.
• Biological sampling (e.g., length, sex, age) is not available for all caught individuals, leading to potential data gaps.

Provenance

Source

Fisheries and Oceans Canada

Collection Method

Standardized longline surveys conducted from chartered commercial fishing vessels, following a random depth-stratified design within 2x2 km blocks.

Time Range

2006 to present, conducted every second year (biennially), with a gap in 2013.

Freshness

Data is updated as of March 2026, with surveys conducted biennially.

Geography

Northern British Columbia coastline, including mainland coast north of Milbanke Sound, Dixon Entrance, and east and west coasts of Haida Gwaii.