Sea and Icelandic Scallop Survey Data from Magdalen Islands (1998-2024)

Fisheries and Oceans Canada has conducted scallop research surveys around the Magdalen Islands since 1985, with detailed biometric data available from 1998 to 2024. The dataset includes three files containing biometrics, individual sizes, and abundances/densities per tow, collected using a lined Digby scallop dredge at depths of 25-35 meters. Data is updated every one to two years, though specific row and column counts are not provided in the input.

Use Cases

• Analyze sea scallop stock status using biometric data on species, size, weights, and sex from 1998-2024.
• Model scallop population densities per tow from 2009-2024 to assess abundance trends in fishing area 20A.
• Compare size distributions of Placopecten magellanicus and Chlamys islandica using individual size data from 2009-2024.
• Investigate potential correlations between scallop biometrics (e.g., size, weight) and their recorded densities from survey tows.

Strengths

• Long-term temporal coverage with biometric data spanning 26 years from 1998 to 2024.
• Standardized collection method using a lined Digby scallop dredge towed for approximately 500 meters at consistent depths of 25-35 meters.
• Data cleaning has been performed to remove aberrant values, and the dataset is updated every one to two years.

Limitations

• Missing data is present in various columns, requiring caution and potential imputation for analysis.
• Abundance and density data for the period 1998-2008 is not included in the main files and is only available upon request.
• The dataset focuses on a specific geographic area (south of the Magdalen Islands, fishing area 20A), limiting broader geographic inference.

Provenance

Source

Fisheries and Oceans Canada

Collection Method

Sampling with a lined Digby scallop dredge at randomly selected stations from a fixed grid, along transects at depths of 25-35 meters.

Time Range

Survey conducted since 1985; detailed biometric data from 1998-2024; size and abundance data from 2009-2024.

Freshness

Updated every one to two years; last updated March 24, 2026.

Geography

South of the Magdalen Islands, fishing area 20A, Canada.