Conservationists fear a highly pathogenic bird flu is to blame for a growing wave of mortality in UK seabirds, which were already facing severe pressure from climate change and overfishing.
The H5N1 avian influenza has killed wild birds including cranes in Israel, Dalmatian pelicans in Greece, knots (a type of shorebird) in the Netherlands and now several UK seabird species, primarily gannets. More than 383,000 bird deaths from the virus have been counted by the World Organisation for Animal Health (WOAH) since October 2021.
About 16,500 of a population of 43,000 Svalbard barnacle geese, which migrate between Scotland’s Solway Firth and Norway’s Svalbard, are estimated to have died during the recent winter, says James Reynolds at the Royal Society for the Protection of Birds, a UK charity.
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“But the epicentre now is…. in Shetland and in the Northern Isles [of Scotland] and it’s also showing up in the Western Isles and around mainland sites,” says Reynolds.
“Wildlife has been particularly affected this [bird flu] season,” says a spokesperson at WOAH. “We are seeing significant mortality in a wider range of wild birds and in various geographical areas, which is unusual.”
Birds have had to cope with avian influenza for thousands of years. However, the illness currently devastating wild birds – predominantly caused by the H5N1 virus – is a recent issue that has its origins in intensive poultry production in east Asia. The flu was first spread through the movement of poultry and is now spreading through the migration of wildlife.
While the flu is unwelcome in wildfowl such as the Svalbard barnacle goose, it is a particularly acute threat for seabirds because they tend to be long-lived species with low reproductive rates. “So even once this wave of disease passes, it’s going to take the populations much longer to recover compared with quite fast-breeding species like geese,” says Stuart Butchart at the non-profit BirdLife International.
The loss of seabirds in the UK has global ramifications because the country is home to so many of them: about two-thirds of the world population of gannets and great skuas are in the UK.
Conservationists say the flu’s impact compounds existing long-term, human-caused pressures. “It’s particularly concerning for the seabirds because they’re being impacted already by fisheries, climate change, disturbance and other threats,” says Butchart.
Reynolds says in the short term, better monitoring and surveillance of flu in wild birds is needed, along with swift removal of carcasses to avoid more birds being infected. The Scottish government has called an urgent meeting for next Monday to see how the RSPB and authorities can better coordinate a national response to the unfolding disaster.
The risk to human health is seen as low. However, people are advised not to touch birds they suspect of being killed by flu. If they find one, they are asked to call a UK government helpline.
Butchart says the loss of wild birds could still have a “huge impact” on the poultry industry by forcing chickens, ducks and geese to be kept indoors, a step which he says will have “massive economic consequences”. UK consumers have only been able to resume buying free-range eggs since 2 May, after UK bird flu control measures introduced last November were relaxed.
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