Scottish Scallop Stocks: Results of 2025 Stock AssessmentsThis report presents the results of Scottish regional king scallop stock assessments carried out by the Marine Directorate (MD) based on commercial catch-at-age data and survey data up to 2024. Full analytical assessments are presented for the East Coast, North East, North West, Shetland and West of Kintyre assessment areas. The report also provides background information on Scottish fisheries for scallops and a description of the current management and regulatory framework. Associated data are presented for download.

]]>fisheriesshellfish abundance and biomass in water bodies2bcd8694-e5fa-4bf1-8dd9-daa1ee661ddf2026-08-24T10:53:25+01:002026-10-16T09:13:37+01:00en-GBPOLYGON ((-9.4921875 55.0555624432, -9.4921875 60.868318167864, 1.0546875 60.868318167864, 1.0546875 55.0555624432))FisheriesScottish Scallop Stock assessment 2025: Summary by areaThe file scallop_stock_assessment_summary_by_area.csv contains the summary outputs from the SAM stock assessment. It includes data from Tables A.11, A.19, A.28, A.37 and A.45 in the report.

The variables in the file are:

Area
Description: Scottish scallop stock assessment area name
Type: categorical
Levels: 5 (East Coast, North East, North West, Shetland, West of Kintyre)
Note: Data are only available for those assessment areas which have an analytical assessment.

Year
Description: calendar year of data
Type: discrete
Range: 1982, 2024
Note: Range of data differs between stock assessment areas

Recruitment estimate
Description: stock assessment estimates of the number of individual scallops recruiting to the stock at age 3 (in thousands).
Type: continuous
Range: 2825, 44990
Note: Values presented are rounded to nearest integer.

Recruitment low
Description: stock assessment estimates of the lower 95% confidence interval on the Recruitment estimate (in thousands).
Type: continuous
Range: 2086, 40626
Note: Values presented are rounded to nearest integer.

Recruitment high
Description: stock assessment estimates of the upper 95% confidence interval on the Recruitment estimate (in thousands).
Type: continuous
Range: 3266, 74097
Note: Values presented are rounded to nearest integer.

SSB estimate
Description: stock assessment estimates of the spawning stock biomass of scallops (in tonnes).
Type: continuous
Range: 3119, 21928
Note: Values presented are rounded to nearest integer.

SSB low
Description: stock assessment estimates of the lower 95% confidence interval on the SSB estimate (in tonnes).
Type: continuous
Range: 2882, 19934
Note: Values presented are rounded to nearest integer.

SSB high
Description: stock assessment estimates of the upper 95% confidence interval on the SSB estimate (in tonnes).
Type: continuous
Range: 3375, 34623
Note: Values presented are rounded to nearest integer.

Fbar estimate
Description: stock assessment estimates of the annual fishing mortality averaged over ages 4 to 8..
Type: continuous
Range: 0.042, 0.454
Note: Values presented are rounded to 3 decimal places.

Fbar low
Description: stock assessment estimates of the lower 95% confidence interval on the Fbar estimate.
Type: continuous
Range: 0.023, 0.385
Note: Values presented are rounded to 3 decimal places.

Fbar high
Description: stock assessment estimates of the upper 95% confidence interval on the Fbar estimate.
Type: continuous
Range: 0.068, 0.605
Note: Values presented are rounded to 3 decimal places.

]]>2026-08-24T10:57:17+01:002026-10-16T09:04:39+01:00text/csvcsv14372https://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/958bcbdd-a568-4acf-8ad6Scottish Scallop Stock assessment 2025: Landings by areaThe file scallop_landings_by_area.csv contains the data presented in Tables A.2, A.3 and A.4 of the report.

The variables in the file are:

Area
Description: Scottish scallop stock assessment area name
Type: categorical
Levels: 9 (Clyde, East Coast, Irish Sea, North East, North West, Orkney, Other, Shetland, West of Kintyre)
Note:

Year
Description: year of landings
Type: discrete
Range: 1982, 2024
Note:

dredge
Description: reported landings of king scallops by UK dredge fishing vessels into Scotland & Scottish vessels abroad (non-UK) in tonnes.
Type: continuous
Range: 0, 4264
Note: Values are rounded to the nearest tonne. NA indicates values not available for some areas and years. * indicates values not displayed due to data confidentiality.

dive
Description: reported landings of king scallops by UK dive fishing vessels into Scotland & Scottish vessels abroad (non-UK) in tonnes.
Type: continuous
Range: 0, 481
Note: Values are rounded to the nearest tonne. NA indicates values not available for some areas and years. * indicates values not displayed due to data confidentiality.

total
Description: total reported landings of king scallops including all fishing gears and all nations (in tonnes).
Type: continuous
Range: 0, 4536
Note: Values are rounded to the nearest tonne. NA indicates values not available for some areas and years. * indicates values not displayed due to data confidentiality.

]]>2026-08-24T11:02:14+01:002026-10-16T09:04:39+01:00text/csvcsv10341https://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/9fc33d87-7e44-4275-a76fScottish Scallop Stock assessment 2025: Catch and mean weight at age by areaThe file scallop_catch_and_mean_weight_at_age_by_area.csv contains the commercial fishery data which are used in the stock assessments. It includes data from Tables A.6, A.7, A.15, A.16, A.23, A.24, A.32, A.33, A.41 & A.42 in the report.

The variables in the file are:

Area
Description: Scottish scallop stock assessment area name
Type: categorical
Levels: 5 (East Coast, North East, North West, Shetland, West of Kintyre)
Note: Data are only available for those assessment areas which have an analytical assessment.

Year
Description: calendar year of data
Type: discrete
Range: 1982, 2024
Note: Range of data differs between stock assessment areas

age
Description: king scallop age class.
Type: discrete/categorical
Range: 3, 10+
Note: The maximum age class is labelled '10+' and includes all scallops at age 10 and older.

Catch
Description: estimated number of king scallops caught in the commercial fishery (in thousands).
Type: continuous
Range: 0, 7334
Note: Values are rounded to nearest integer. NA indicates values not available for some areas and years.

Mean weight
Description: mean weight of an individual scallop caught in the commercial fishery (in kg).
Type: continuous
Range: 0.107, 0.324
Note: Values are rounded to 3 decimal places.

]]>2026-08-24T11:04:31+01:002026-10-16T09:04:39+01:00text/csvcsv54614https://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/f8251c8b-35e1-4dcf-972dScottish Scallop Stock assessment 2025: Survey catch rate at age by areaThe file scallop_survey_catch_rate_at_age_by_area.csv contains the research vessel survey data which are used in the stock assessments. It includes data from Tables A.9, A.17, A.26, A.35 and A.43 in the report.

The variables in the file are:

Area
Description: Scottish scallop stock assessment area name
Type: categorical
Levels: 5 (East Coast, North East, North West, Shetland, West of Kintyre)
Note: Data are only available for those assessment areas which have an analytical assessment.

Year
Description: calendar year of data
Type: discrete
Range: 1993, 2024
Note: Range of data differs between stock assessment areas

age
Description: king scallop age class.
Type: discrete/categorical
Range: 3, 10+
Note: The maximum age class is labelled '10+' and includes all scallops at age 10 and older.

Catch.rate
Description: research vessel survey catch rate of king scallops (in numbers per hour per metre dredge width).
Type: continuous
Range: 0.071, 15.599
Note: Values are rounded to 3 decimal places. NA indicates values not available for some areas and years.

Survey
Description: Research vessel/survey name.
Type: categorical
Levels: 4 (Alba, Aora I, Aora II, Clupea)
Note:

]]>2026-08-24T11:06:32+01:002026-10-16T09:04:39+01:00text/csvcsv46373https://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/dbf06ed2-5483-48c0-8a81Scottish Scallop Stock assessment 2025: Abundance and fishing mortality at age by areaThe file scallop_abundance_and_fishing_mortality_at_age_by_area.csv contains the estimates of stock abundance and fishing mortality at age from the SAM stock assessments. It includes data from Tables A.13, A.14, A.21, A.22, A.30, A.31, A.39, A.40, A.47 and A.48 in the report.

The variables in the file are:

Area
Description: Scottish scallop stock assessment area name
Type: categorical
Levels: 5 (East Coast, North East, North West, Shetland, West of Kintyre)
Note: Data are only available for those assessment areas which have an analytical assessment.

Year
Description: calendar year of data
Type: discrete
Range: 1982, 2024
Note: Range of data differs between stock assessment areas

Age
Description: king scallop age class.
Type: discrete/categorical
Range: 3, 10+
Note: The maximum age class is labelled '10+' and includes all scallops at age 10 and older.

Abundance
Description: stock assessment estimates of the abundance of king scallops (number of individuals in thousands).
Type: continuous
Range: 364, 44990
Note: Values presented are rounded to nearest integer.

Fishing mortality
Description: stock assessment estimates of the annual fishing mortality.
Type: continuous
Range: 0.0003, 0.7118
Note: Values presented are rounded to 4 decimal places.

]]>2026-08-24T11:08:30+01:002026-10-16T09:04:39+01:00text/csvcsv57792https://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/80fc7350-31a1-46f7-b55eScottish Scallop Stock assessment 2025: Estimated parameters by areaThe file scallop_estimated_parameters_by_area.csv contains the parameter estimates from the SAM stock assessments. It includes data from Tables A.12, A.20, A.29, A.38 and A.46 in the report.

The variables in the file are:

Area
Description: Scottish scallop stock assessment area name
Type: categorical
Levels: 5 (East Coast, North East, North West, Shetland, West of Kintyre)
Note: Data are only available for those assessment areas which have an analytical assessment.

Parameter
Description: parameter identifier as used in the SAM stock assessment
Type: categorical
Levels: 37
Note: The parameter identifier can have a different meaning for different assessment areas.

Parameter estimate
Description: parameter value estimated by the stock assessment on log scale.
Type: continuous
Range: -10.1793, 2.1493
Note:

Parameter sd
Description: standard deviation of the parameter value estimated by the stock assessment on log scale.
Type: continuous
Range: 0.0465, 0.8855
Note:

Exp parameter
Description: parameter value estimated by the stock assessment transformed to natural scale.
Type: continuous
Range: 0.000040, 8.578790
Note:

Low
Description: lower 95% confidence interval of the parameter estimate on the natural scale.
Type: continuous
Range: 0.000030, 6.531840
Note:

High
Description: upper 95% confidence interval of the parameter estimate on the natural scale.
Type: continuous
Range: 0.000060, 11.267210
Note:

]]>2026-08-24T11:10:43+01:002026-10-16T09:04:39+01:00text/csvcsv10046https://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/a252b093-8680-439f-b37eReport: Scottish Scallop Stocks: Results of 2025 Stock AssessmentsAccess the report on the Scottish Government publications

]]>2026-10-09T10:44:48+01:002026-10-16T09:13:37+01:00htmlhttps://data.marine.gov.scot/dataset/scottish-scallop-stocks-results-2025-stock-assessments/resource/1b6c2902-8c63-40b2-928aDKANhttps://data.marine.gov.scot