Shetland nature reserves see increase in seabirds
There has been an 83 per cent decline in great skuas since 2018.
Great skua populations have risen, but remain low.

A census of seabirds in Scotland’s Shetland Islands has found that many of its seabirds had seen an increase in population on the previous year.

The statistics revealed that populations of the great skua at the Shetland National Nature Reserves (NNRs) had increased since 2023, although they still remained significantly lower than before the outbreak of avian influenza in 2022.

This year’s census at the Hermaness NNR found 220 breeding pairs of great skuas, compared to 208 breeding pairs in 2023. Despite this slight increase, this is a 77 per cent decline since 2018 – the last census completed before the avian influenza outbreak. In 2018, there were 955 breeding pairs of great skuas.

Similarly, a count at the Noss NNR found just 80 pairs of great skua, compared to 69 in 2023. This is still an 83 per cent decline since 2018, when 476 breeding pairs were counted.

Conservationists at NatureScot are also concerned for the status of gannets in the Shetland Islands, as this species was also impacted by the avian influenza outbreak.

Although no formal count was carried out this year, gannet numbers are believed to be higher in 2024. However, NatureScot estimates that the conservation of this species has been set back 20 years by the outbreak.

In 2021, there were 29,562 gannet nests at the Hermaness site. This dropped to just 18,739 nests in 2023.

There was only one positive case of avian influenza among the seabirds during the breeding season, however there were a small number of positive H5N5 cases among black-backed gulls and great skuas at the end of the season.

Juan Brown, NatureScot operations officer, said: “This year’s seabird census reveals the ongoing impact of the avian flu outbreak in 2022 and the painfully slow recovery of these populations which are likely to take years, if not decades, to reach pre-outbreak levels once again.

“In contrast to recent years, the small number of positive avian flu tests we have had this year have all been the H5N5 strain of the virus, rather than H5N1.

“While we don’t yet know what the impact of H5N5 will be on wild bird populations, we are keeping a close eye on the situation and encourage people to report all sightings of sick or dead birds using the GB online reporting system. Sightings will help us track the spread of the virus and assess impacts on wild bird populations.”

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