The UK has lost more than three-quarters of its great skuas on surveyed sites since bird flu struck, according to the first report quantifying the impact of H5N1 on seabird populations.

The deaths have happened over two years, since the outbreak of H5N1 in 2021. The UK is internationally important for seabirds, home to most of the world’s 16,000 pairs of nesting great skuas.

Jean Duggan, a policy assistant on avian influenza for the Royal Society for the Protection of Birds (RSPB), said: “To have that level of loss in a population we have international responsibility for is quite catastrophic.