The UK's largest conservation charity has called for a moratorium on the release of gamebirds amid an "unfolding catastrophe" affecting wild birds. 

The Royal Society for the Protection of Birds (RSPB) warned that the release of birds for shooting could see cases of avian flu spread rapidly across inland areas. 

Populations of birds across Scotland have been devastated by the worst outbreak of the virus in the UK to this date. 

Seabirds and coastal colonies have been particularly hit by the highly pathogenic variant - with great skua reaching a global extinction risk. 

Nature Scot previously confirmed the population of great skua, also known as bonxies, has already decreased by 85% in Orkney. 60% of the world population of this species breeds in the UK.

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Globally important colonies have seen both adult birds dying and a "near total" failure in breeding. 

The RSPB is concerned the release of millions of pheasants and ducks which are reared to be shot could bring the outbreak to less affected areas.

Director of policy Jeff Knott said: "In recent months we have witnessed an unfolding catastrophe taking place on our wild birds.  

"It has been emotionally tough to witness, but we are not helpless and there are many positive actions that we can take to help them weather this storm and reduce the risk of exacerbating this crisis.

Every year around 55 million pheasants and red-legged partridges and 2.6 million mallard ducks are released in the UK for shooting. 

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The RSPB emphasised this represents more than the total biomass of all UK native birds.

It urged for the release to be stopped for this year to limit the impacts of the avian influenza outbreak.

This would be done on a precautionary basis as the spread of the virus from pheasants to wild birds is yet to be scientifically confirmed. 

According to the UK Government’s Animal and Plant Health Agency (APHA), transmission between pheasants and wild bird is possible as different pathogens have been shown to spread between the animals.

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Mr Knott added: “In recent months we have witnessed an unfolding catastrophe taking place on our wild birds.

"It has been emotionally tough to witness, but we are not helpless and there are many positive actions that we can take to help them weather this storm and reduce the risk of exacerbating this crisis.

"This disease originated in poultry in Asia before passing into wild birds. It is another human pressure on beleaguered wildlife across the world and in the UK specifically.

"We must all now take responsibility and do everything we can to limit the impact in the immediate term, and to implement and fund species conservation programmes to build resilience in our wildlife for the future.”

However, the British Association for Shooting and Conservation (BASC) claims that the industry "all necessary actions to reduce the transmission of avian flu are taken". 

Glynn Evans, BASC head of game and gundogs, said: “For a national conservation charity, this political grandstanding campaign shows a fundamental lack of understanding of avian influenza, the Government’s strategies to combat it or how gamebird release is managed. The RSPB has failed to present a single piece of evidence to support their call and has chosen to ignore the substantial role shooting plays in the countryside.

“Shooting is worth £2 billion to the UK economy, providing the equivalent of 74,000 full-time jobs. It is a significant contributor to conservation, rural jobs and the local economy.

“This year’s outbreak of avian influenza is of serious concern and BASC and other representatives of the shooting sector have been working closely with Defra, the devolved administrations and a wide range of stakeholders to ensure all necessary actions to reduce the transmission of avian flu are taken. The RSPB would better serve their members by doing likewise.”