Fish Density Maps for Newfoundland Shelves from 1981 to 2017

Fisheries and Oceans Canada provides average relative density maps for fish functional groups and species in the Newfoundland and Labrador Shelves Bioregion. The dataset spans 37 years from 1981 to 2017, derived from multispecies research vessel surveys. It includes eight functional groups and 40 individual species, with data processed into 4x4km resolution rasters.

Use Cases

• Model spatial distribution patterns for eight fish functional groups, such as small benthivores and piscivores, using the 4x4km resolution raster data.
• Analyze long-term biomass trends for 40 mapped species, including dominant and at-risk species, using the standardized kg/tow values from the composite dataset.
• Assess habitat importance for marine spatial planning by mapping persistent areas of high and low density from the kriged average relative density surfaces.
• Compare fish community structure between the Engel (pre-1995) and Campelen (post-1995) gear time series using the filtered core strata data.

Strengths

• Covers a 37-year time series from 1981 to 2017, providing a long-term ecological perspective.
• Includes data for eight defined functional groups and 40 individually mapped species, including at-risk categories.
• Spatial data is processed into a continuous raster with a standardized 4x4km resolution.

Limitations

• Survey data is split into two separate time series due to a gear change in 1995, complicating direct temporal comparisons.
• Analysis is limited to core strata, excluding most deep water and inshore sets which may bias the density maps.
• Data is aggregated into average relative density maps, so original raw catch records per tow are not provided.

Provenance

Source

Fisheries and Oceans Canada, Science Branch, Newfoundland and Labrador region.

Collection Method

Derived from stratified random multispecies research vessel surveys, with biomass (kg/tow) data processed via log transformation and ordinary kriging.

Time Range

1981 to 2017, inclusive.

Freshness

Data covers up to 2017; the metadata was last updated in March 2026.

Geography

Newfoundland and Labrador Shelves Bioregion, specifically NAFO Divisions 2J3KLNOP and 2H.