C11: Productive seas: status of sensitive fish and shellfish stocks
Short Description
This indicator tracks changes in the population status (occurrence, abundance and condition) of fish and shellfish species at risk of depletion. The indicator is derived from individual species assessments based on scientific survey data; note that a subset of species may also be included in indicator ‘C6 Diverse seas: status of threatened and declining features’. Species considered at risk will be assessed to account for the impact of change in environmental conditions and human activities to identify if species are adversely impacted by human activities. The indicator is linked to the UK Marine Strategy Descriptor 1 (biodiversity) and the Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR).
Readiness and links to data
This indicator is not available for reporting in 2024 in a finalised form. An interim indicator is presented here based upon individual species assessments conducted for OSPAR common indicator “Recovery in the Population Abundance of Sensitive Fish Species”, produced as part of the OSPAR Quality Status Report (QSR) 2023. Species are assessed for evidence of a significant increase or decrease in frequency of occurrence across the assessment period (2015 to 2020) compared to a reference period. There is an aspiration to reverse any long-term depletion of species populations, so the basis of the assessment is a long-term reference period inclusive of all years prior to the assessment period for which there are robust survey data (that is 1983 to 2008). To identify whether depletion is ongoing or if signs of recovery are evident, a secondary short-term reference period is also defined (here, 2009 to 2014).
The indicator provides an assessment of change in the occurrence of species identified as sensitive to fishing. Where data allow, those species that fail this occurrence assessment will be analysed further to identify any change in abundance and condition (population age and size structure) (see Bluemel et al., 2021 for a comprehensive example using this methodology).
Indicator components
Figure C11: Long-term and short-term changes in the occurrence of sensitive fish species, Greater North Sea and Celtic Seas, 1983 to 2020
Table C11: Long-term and short-term changes in the occurrence of sensitive fish species, Greater North Sea and Celtic Seas, 1983 to 2020
| Ospar region | Time period | Declining | Mixed | Recovering | Stable |
|---|---|---|---|---|---|
| Celtic Seas | Long term (1983-2014 to 2015-2020) | 15.38 | 11.54 | 46.15 | 26.92 |
| Celtic Seas | Short term (2009-2014 to 2015-2020) | 18.52 | 3.70 | 44.44 | 33.33 |
| Greater North Sea | Long term (1983-2014 to 2015-2020) | 15.15 | 6.06 | 42.42 | 36.36 |
| Greater North Sea | Short term (2009-2014 to 2015-2020) | 12.12 | - | 48.48 | 39.39 |
Trend description for C11
In the Celtic Seas, over the long term, 4 (15%) of the 26 species assessed show a significant decline in occurrence over the assessment period (2015 to 2020) compared to the long-term reference period (1983 to 2008). In the short term, 5 (19%) of the 27 species assessed show a significant decline in the assessment period compared to the short-term reference period (2009 to 2014). A further 12 (46%) of the species assessed are recovering in the assessment period compared to the long-term reference period, very similar to the number of species (12, or 44% of those assessed) that are shown to be recovering in the assessment period compared to the short-term reference period.
In the Greater North Sea, over the long term, 5 (15%) of the 33 species assessed show a significant decline in occurrence across the assessment period (2015 to 2020) compared to the long-term reference period (1983 to 2008). In the short term, 4 (12%) of the 33 species assessed show a significant decline in the assessment period compared to the short-term reference period (2009 to 2014). A further 14 (42%) of the species assessed are recovering in the assessment period compared to the long-term reference period. When comparing the assessment period to the short-term reference period, it is evident that 16 species (48%) have been showing signs of recent recovery.
Assessment of change
No assessment of change was undertaken for this indicator as a suitable time series is not yet available in the Outcome Indicator Framework.