Juvenile Pacific Salmon Abundance Estimates in Strait of Georgia 2010-2020

Spatial estimates of juvenile Pacific salmon abundance were generated from 1,588 fishery-independent survey sets conducted between 2010 and 2020. The dataset provides predicted catch per unit effort (CPUE), its year-to-year variation, and prediction uncertainty for five salmon species at a 0.5 km resolution. These results, produced by Fisheries and Oceans Canada using a spatiotemporal generalized linear model, illustrate habitat use across summer and fall seasons to support marine spatial planning.

Use Cases

• Model spatiotemporal patterns of predicted catch per unit effort (CPUE) for five Pacific salmon species across summer and fall seasons.
• Analyze year-to-year coefficient of variation (CV) of CPUE to identify areas with stable versus variable juvenile salmon abundance.
• Compare binned biscale measures of mean CPUE vs. CV to distinguish consistently high-abundance habitats from 2010 to 2020.
• Support marine spatial planning by mapping the 0.5 km resolution predictions of juvenile salmon distribution in the Strait of Georgia.

Strengths

• Model outputs are based on 1,588 standardized fishery-independent survey sets conducted over 11 years (2010-2020).
• Provides continuous estimates at a high 0.5 km spatial resolution for the majority of the Strait of Georgia.
• Covers all five species of Pacific salmon with predictions for both summer (June-July) and fall (September-October) seasons.
• Includes multiple analytical outputs: mean CPUE, year-to-year coefficient of variation, and binned biscale measures.

Limitations

• For pink salmon, the analysis only includes even-year surveys due to their two-year life cycle, creating a data gap for odd years.
• Predictions are based on a model (sdmTMB) and are synthetic estimates, not direct observational counts.
• The survey dataset is limited to sets lasting 12-50 minutes at depths ≤60m, which may not capture all habitat conditions.

Provenance

Source

Fisheries and Oceans Canada

Collection Method

Estimates generated using a spatiotemporal generalized linear model (sdmTMB) applied to standardized mid-water trawl survey data.

Time Range

2010 to 2020

Freshness

Data covers 2010-2020; metadata was last updated in March 2026.

Geography

Strait of Georgia, Pacific Region of Canada