Ospar Commission
OSPAR's Quality Status Report 2023 Friday Ocean Findings Issue 37
Marine food webs describe the interconnectedness between different species and habitats. They can be used to illustrate and understand the relationships between predators and prey, the way in which energy flows through marine ecosystems and the way in which ecosystems function.

Our 2 food web Indicator assessments and the pilot assessment featured in this week's Friday Ocean Findings contribute to our 2023 Quality Status Report which, when viewed together, build a picture of the overall condition of the marine environment of the North-East Atlantic and progress towards achieving our vision of a clean, healthy and biologically diverse North-East Atlantic Ocean, which is productive, used sustainably and resilient to climate change and ocean acidification. The results will also be used by OSPAR Contracting Parties to inform policy decisions.

We hope you enjoy these Indicator Assessments. Please contact us with any comments at [email protected]
Proportion of Large Fish (Large Fish Index)

Long-term declines are evident in the Greater North Sea and Celtic Seas. No change was found in the Bay of Biscay and Iberian coast or Wider Atlantic. The recoveries noted in IA2017 stalled prior to 2020 and thresholds were not met in the North Sea or West of Scotland subdivisions.

Changes in Average Trophic Level of Marine Consumers

The Mean Trophic Level (MTL) showed contrasting trends in the four sub-divisions of the Bay of Biscay and Iberian Coast over recent decades. Although signs of recovery of top predators and mesopredators are observed in most sub-divisions, there were downward trends in some local areas.

Pilot Assessment of Primary Productivity

Primary production sustains the functioning of marine food webs. Over the long-term (1997-2019) primary production was stable in the Greater North Sea, Celtic Seas and Bay of Biscay and Iberian Coast. Significant decreases occurred between 2015 and 2019, likely driven by reduced nutrient availability and climate change, which may disturb higher trophic levels.

Further information

For more information on OSPAR's work please visit our website.

OSPAR Commission
https://www.ospar.org/ | [email protected]
Telephone: +44 (0) 20 7430 5200
The Aspect, 12 Finsbury Square, London, EC2A 1AS, United Kingdom
To unsubscribe from this newsletter, please email [email protected]