Demersal Fish and Benthic Invertebrate Assemblages in the Northwest Atlantic

December 2024 data from four regional annual multispecies trawl surveys in the Northwest Atlantic, used to characterize mesoscale biological assemblages. The analysis identified 3 to 6 predominant assemblage types per region, with indicator analyses selecting 3–34 emblematic taxa for each type. Random forest models predicted assemblage distributions from environmental covariates with high accuracy (AUC > 0.95).

Use Cases

• Apply hierarchical clustering on species occurrence data from trawl surveys to identify 3-6 predominant assemblage types per survey region.
• Use indicator analyses to identify the 3–34 emblematic taxa associated with each delineated assemblage type.
• Train random forest classification models using environmental covariates like annual minimum and maximum bottom temperatures to predict assemblage distributions.
• Project future assemblage distributions for the Scotian Shelf-Bay of Fundy region under a high emissions climate scenario (RCP 8.5) for the year 2075.

Strengths

• Analysis based on data from four distinct regional annual multispecies trawl surveys.
• Random forest classification models achieved high predictive accuracy with AUC scores greater than 0.95.
• Indicator analyses identified a specific range of 3 to 34 emblematic taxa for each assemblage type.

Limitations

• The specific number of rows (survey records) and columns (variables) is not provided in the input.
• Data is derived from trawl surveys, which may have spatial and temporal sampling gaps.
• Future projections are based on a single climate scenario (RCP 8.5) for the year 2075, representing one possible outcome.

Provenance

Source

Fisheries and Oceans Canada, Coastal Ecosystems Science Division, Maritimes region.

Collection Method

Data gathered from four regional annual multispecies trawl surveys, analyzed using hierarchical clustering and random forest classification.

Time Range

Survey years not specified; analysis published in December 2024.

Freshness

Published in December 2024, with metadata last updated in March 2026.

Geography

Northwest Atlantic, specifically including the Scotian Shelf-Bay of Fundy region.