Plastic monitoring in seabirds nests

The Mediterranean Science Commission (CIESM) launched a new initiative in 2021 to monitor marine litter in the nests of the European Shag (Phalacrocorax aristotelis). This species has the particularity to use marine litter collected at sea as nest-building material, which would make it most appropriate as an indicator of marine litter pollution in nearby coastal waters.

European Shag (Phalacrocorax aristotelis)
(photo: H. Foxonet)
Example of a nest containing marine litter items (photo: B. Cadiou)

This initiative aims to test the relevance of an original indicator of coastal pollution through a relatively simple, once-a-year monitoring using a standardized protocol across the Mediterranean basin and adjacent coasts. The resulting index could then be used as a tool for the protection of threatened MPAs and coastal habitats.

The first pilot survey conducted in 2021 in four countries covered a total of 452 nests in 25 colonies / sub-colonies of European shags (see map above and click on each dot for details).

Of all the polluted nests assessed, two third included plastics, mostly consisting of plastic bags, fishing gear and ropes, and a diversity of debris of various origins and colors.

The next annual survey will see a geographic extension of the field sites.
If your institute is interested in participating, please contact us.