This indicator will track the health of our seas using metrics based on the size, structure and function of different feeding (trophic) levels in marine food webs. The indicator will focus on pelagic (water column) habitats and populations of key species groups within the food web. The indicator will also link to and complement C9 ‘Healthy seas: Seafloor habitats functioning’. These show whether ecosystems are healthy and are being used sustainably. Currently, the metrics within this indicator are being developed for the UK Marine Strategy Descriptors 1 (biodiversity), 4 (food webs) and 6 (seafloor integrity) 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 2023 as development is required. Research is underway to further develop the food web metrics that constitute this indicator. Analytical methods and some data on food webs are available.
A pilot assessment of feeding guilds has been published as part of the OSPAR Quality Status Report 2023. These feeding guilds were applied to assess change in fisheries-independent survey data, revealing spatial aggregations of feeding guilds, and regions of change over time indicative of change in ecosystem structure and function. Ongoing developments include the collation of more stomach content data to further resolve predator diets. Stomach content data are publicly available from International Council for the Exploration of the Seas (ICES) Fish-stomach data portal (Fish stomach (ices.dk)) and the Cefas Integrated Database and Portal for Fish Stomach Records. Fisheries-independent survey data are also available from ICES Database of Trawl Surveys (DATRAS)