High levels of plastic found in Scottish seabird nests
Four in 10 seabird nests surveyed on the uninhabited Lady Isle in the Firth of Clyde contained plastic, with varying amounts found in those different species.
In the survey, carried out in May 2018, researchers examined 1,597 nests on the island off the Ayrshire coast and found that 625 had some plastic incorporated into it. The man-made material was was found in 24.8% of Great Cormorant nests, while for Lesser Black-backed Gulls it was 25%. More than a third of European Herring Gull nests surveyed on the inhabited isle held plastic, while for Great Black-backed Gull it was 53.5% and a whopping 80% for European Shag.
Some 80% of European Shag nests on Lady Isle contained plastic (Martin Webb).
Researchers from the University of Glasgow examined the nests and suggested the plastic was washed to the island, where it was collected by birds and incorporated into the structures. It's possible that plastic could affect the quality of nests, with detrimental effects for the eggs and chicks, while there is also a risk birds could become tangled up in it, or indeed sick through ingesting it.
Dr Ruedi Nager, a seabird ecologist and senior lecturer at the University of Glasgow, said: "They end up in seabird nests, not because seabirds actively pick them up in built-up areas and carry them to their nest, but because are brought there passively by marine currents."
It mapped all nests on Lady Isle and tested whether nests with plastic were equally distributed across the island. Results showed nests on the north of the island, which are closer to the outgoing tide from the mainland, were more likely to contain plastic. This suggests the plastic in the nests originally came from the mainland and was washed up on the shore where the birds could collect it from the immediate surroundings of their nests.