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Today’s blog is written by Claire Smith, Senior Policy Officer – Avian Influenza, on the the spread of Avian Influenza and the RSPB's call for a moratorium on the release of captive game birds this year in the UK.
To help limit the catastrophic spread of Avian Influenza, the RSPB is calling for an immediate moratorium on the release of captive bred gamebirds and Mallards for shooting in the UK this year. The call is for the UK and devolved governments and the shooting industry to take a precautionary approach to limit the spread of avian influenza in wild birds and reduce the risk of viral re-assortment leading to new strains of the disease.
Every year over 40 million Pheasants and Red-legged Partridges and 2.6 million Mallard ducks are reared in captivity and then released into the UK countryside to be shot for sport. Many of these birds are imported from Europe then held in pens to mature prior to release. Others are reared in game farms across the UK. Releases will start in July and August but prior to that birds may be moved from game farms to release pens which are often un-roofed with access to wild birds.
Following the lifting of the housing order in England and Wales (which required poultry to be kept inside) gamebirds are now permitted to be released across the country, with the exception of temporary 3km and 10km disease control zones put in place following an outbreak in captive birds. Additionally, last week Natural England announced restrictions on releasing gamebirds on or near to protected areas to reduce the avian influenza risk to birds of conservation concern breeding on these sites.
Whilst RSPB welcomes these restrictions, they do not go far enough. They only apply in England and we are disappointed that Mallards have not been added to the General Licence.
Defra’s risk assessment on the spread of Highly Pathogenic Avian Influenza (HPAI) from Pheasants to wild birds concluded the release of captive bred Pheasants had a very high likelihood of infecting one or more wild birds with HPAI near release sites and that “that the release of these gamebirds could provide an additional source of susceptible birds which could serve as a reservoir of H5N1 and present a mechanism to maintain the virus in Great Britain over the late summer/early autumn in the months leading up to the arrival of large numbers of migratory wild birds.” Released Pheasants could also represent a “population where viral re-assortment could occur.”
As symptoms can take several days to develop infected, birds may not be spotted before being released and after this are considered by Defra to be ‘wild birds’ with no legal obligation on a shoot to then report an outbreak. Feeding sites attract wild birds promoting infection and transmission and infected gamebird carcasses can transmit infection to raptors and other scavengers.
The risk assessment also recognises the issue of ‘limited data on pheasant numbers and the locations of release sites…’ which will hinder the enforcement of preventing gamebird releases in disease control zones.
Whilst Defra focused on Pheasants as constituting the largest numbers of released gamebirds in the UK, RSPB has concerns about the role of Mallard releases in the spread of HPAI which we have flagged with Defra and the UK Statutory Nature Conservation bodies.
Mallards are particularly susceptible to infection with H5N1 and ducks are known to shed the virus for long periods, often whilst asymptomatic and therefore once released, pose a risk to wild birds using waterbodies, including at designated sites. Flight ponds used for wildfowling will also attract wild birds due to feeding, habitat improvements and decoy ducks.
RSPB called for a moratorium on gamebird releases last year which went un-heeded. Since 2021 there have been 10 outbreaks in gamebird rearing premises. One in Scotland, five in England and four in Wales. This includes the most recent at Bettws Hall Game Farm, near Newtown, Powys.
Defra’s statistics on HPAI in wild birds show 70 positive tests in Pheasants in 2022 from August to December, with a peak occurring in October. These have occurred predominantly in England, with 9 positive tests in Wales and 4 in Scotland. In Northern Ireland, there have also been at least two positive tests in pheasants (not included in Defra data).
There are many transmission routes involved in the spread of Avian Influenza and as we see increased outbreaks at Black-headed gull colonies across the UK. RSPB is calling for an immediate moratorium on gamebird releases to try and reduce the risks to our wild bird populations. You can read more about our other asks in a previous blog here and more about bird flu and RSPB’s work here.