The Farne Islands cared for by The National Trust in the North Sea. Credit: Nick Upton / National Trust.
The Farne Islands cared for by The National Trust in the North Sea. Credit: Nick Upton / National Trust.

Avian flu: devastating impact on wild seabird colonies

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National Trust reports impact at five sites (compared to one in 2022)

More than 7000 seabirds have died from Avian flu in coastal areas around England, Wales and Northern Ireland, says The National Trust. The losses have occurred during the course of the year.  

Areas impacted include: the Farne Islands, Long Nanny and Cemlyn with fatalities also being seen in Brownsea, South Wales and Northern Ireland.

The charity adds the spread of the virus is having a, ‘devastating impact on wild seabird colonies at National Trust sites.’

It says it saw the disease at just one of its sites last year and that this year has already seen the virus impact five of its colonies. It’s concerned that the disease could have a devastating impact on rarer species if it continues to ‘go unchecked.’

Experts say kittiwakes, large gulls and rare Arctic terns are most impacted by the disease on the Farne Islands this year. This is compared to Guillemots, Kittiwakes and Puffins which suffered the most in 2022.

The team say a ‘devastating percentage’ of rare Arctic terns have perished at Long Nanny – with a minimum of 8% of breeding adults and approximately 40% of chicks succumbing to the disease.

The charity says 40% of this year’s breeding Arctic tern adults and 55% of breeding Sandwich tern adults have died at Cemlyn in North Wales. 

They add that ‘bird flu poses a significant threat to seabirds such as Arctic terns and there is a serious risk of population decline across breeding sites if we can’t combat the disease.’

The charity’s noted that Blakeney Point on the north Norfolk coast is the only one of its significant sites for seabirds to escape disease relatively unscathed – with a good breeding year for Little terns.

‘Bird flu: a major issue for seabirds’

‘Bird flu is still a major issue for our seabirds, and it has not only been distressing for our teams to witness how it has spread to other species and sites this year, but we know how upsetting it has been for visitors too,’ says Ben McCarthy.

Ben is the Head of Nature Conservation and Restoration Ecology at the National Trust. 

‘Working with our teams on the ground as well as national partners such as British Trust for Ornithology, we are monitoring our key sites and building a better evidence base to help understand how best to tackle the disease.’

‘But what we urgently need is long term coordinated research across key sites so impacts on our internationally important seabirds can be mitigated.’ 

‘It is apparent that this disease is likely to remain shifting from species to species and we must swiftly develop a coordinated approach to monitoring and implementing conservation measures across national governments, statutory agencies, researchers and conservation organisations to stand any chance of protecting our important populations of seabirds.’

‘This disease adds to other pressures impacting our seabirds, a key indicator of the state of our seas.’

‘The impact we are now witnessing due to climate change, including warming seas, stormier weather impacting breeding sites, and the availability of the fish the birds feed on all compound the pressures on these magnificent species.’ 

‘We need to see urgent Government action to tackle the climate and nature crisis.’

Farne Islands: remaining closed for remainder of season

The National Trust has added that the Farne Islands will remain closed to visitor landings for the remainder of the visitor season. The measure will allow rangers to deal with the impacts of the disease. Sail around boat tours of the Farne Islands will continue.

This will include catching up with habitat management work to help ensure the best breeding conditions possible for birds returning next year.

In 2022, the conservation charity saw the disease rip through many species of seabirds on the Farne Islands, off the coast of Northumberland. The site saw the virus cause the deaths of more than 6,000 birds.

This year the number of dead birds picked up on the Farne Islands is just over half that number. The ranger team are engaged in the regular collection of dead birds to try to stop the spread of the disease. 

The charity says it’s a ‘much bleaker picture for other sites with five additional notable areas for seabird colonies impacted.’

Rangers wearing PPE clear bird carcasses from the Farne Islands in August 2022. Credit: National Trust Images.

These areas include Long Nanny, on the Northumberland coast, Cemlyn in Anglesey, North Wales, Brownsea off the south coast of Dorset, Pembrokeshire coast in South Wales. Some areas on the East and North coasts of Northern Ireland are also affected.

Teams are ‘anxious’ to see what impact disease has on returning seabirds

‘Migrating seabirds such as Kittiwakes, Puffins and terns return to the Farnes each year in March for the breeding season,’ says Harriet Reid, Area Ranger on the Farne Islands which is cared for by The National Trust. 

‘This year we were anxious to see whether we’d once again witness the tragic impact of the disease on the returning seabirds after the disease hit us hard last year.’ 

‘As soon as we became aware of the presence of avian flu within the bird population, we did everything possible to restrict the spread of the disease and closed the island to visitors.’

‘This meant less disturbance for the vulnerable colonies, and we took the decision to pick up dead birds to try and counter the spread of the disease.’ 

‘Removing the seabirds as soon as we find them, does seem to have made a difference.’

The team note that the number of dead birds picked up on the islands is down by 39% on last year.

‘Currently there is little solid guidance and we’re fighting against time to prevent a long-term impact on some populations, particularly those species which are already struggling due to other pressures such as climate change. Last year it was the Guillemots and Kittiwakes that were most impacted.’ 

The National Trust say there is currently no way of protecting seabirds against the spread of the disease.

This year, more than 1,300 Arctic terns died with the ranger team collecting 1,066 chicks and 263 adults, as well as19 Little tern chicks and 10 adults.

‘Heartbreaking to witness so many birds… succumb to the disease’

‘We started to see birds showing signs of the disease in late June and it was absolutely heartbreaking to witness so many birds, particularly Arctic tern chicks, succumb to the disease,’ says James Porteus.

James is the Area Ranger at Long Nanny which is home to Britain’s largest mainland colony of Arctic terns.

‘What is really concerning is the number of both Arctic and Little terns that we have lost in relation to the respective populations that typically return here to breed.’ 

‘At least 8% of the breeding population of Arctic tern adults died this season, along with roughly 40% of the Arctic tern chicks. Similarly, the losses of Little terns equate to 13.5% of the breeding adult population.’

Ranger working at Long Nanny after a suspected outbreak of bird flu. Credit: Kate Phillips

‘This is extremely worrying, especially when you consider that these fragile seabirds are already having to deal with a whole host of other challenges including the impacts of climate change and extreme high tides wiping out nests at critical times during the breeding season.’ 

‘This year’s losses could take years to recover from, and that’s before we consider how this indiscriminate disease might impact the colony once again next year.’ 

Working hard to give them ‘best possible chance’

Cemlyn in North Wales has seen more than 1200 dead birds collected by the team. The site is owned by the National Trust but is cared for by the North Wales Wildlife Trust. More than 700 were Sandwich terns and the majority were chicks. 

‘Last year our seabirds escaped bird flu, so it has been really distressing to see its impact here, over the past few months,’ says Chris Wynne, Senior Reserves Manager for the North Wales Wildlife Trust. 

‘Hazardous migrations bring them back to only a small handful of sites on Anglesey where they are vulnerable to predation, weather and human disturbance.’ 

‘Everyone involved, and it takes an extraordinary partnership of agencies and individuals, works hard to give them the best chance possible.’ 

‘Overall, the past few years have seen the populations bounce back from significant local issues and we were hopeful that the populations would continue to maintain this recovery.’ 

‘But this is a significant setback for them; and we are anxious what the 2024 season will bring.’

‘We will continue to maintain Cemlyn as a breeding site and work with Welsh Government and Natural Resources Wales to give terns and all seabirds the best chance they can have.’

South Wales is also impacted. On the Pembrokeshire coast, hundreds of dead wild birds were washing up on beaches and confirmed as having Avian flu in July. 

Dead birds were found on three beaches cared for by National Trust Cymru. A total of 201 birds were picked up. Guillemots were impacted the most. 

Just over 1,000 birds have been recorded by all agencies together in the region. The numbers are now steadily decreasing.

At Brownsea island, in Dorset, 650 birds perished with the vast majority being chicks or juveniles. The National Trust and the Dorset Wildlife Trust Rangers collected 243 Black-headed gulls, 223 Common terns and 166 Sandwich terns.

In Northern Ireland, The National Trust rangers collected 21 dead common terns from Cockle Island, a breeding colony just off the coast of Groomsport which is typically home to breeding seabirds each summer.

In 2021 and 2022, there were only 13 breeding pairs of common tern on the island. The charity says these losses will have a major impact on the population.  

Blakeney Point: a ‘good year’ for chick numbers

The one National Trust site that appears to have escaped the disease relatively unscathed was Blakeney Point which is on the north Norfolk coast. It’s home to an important breeding colony of Little terns. 

This year the rangers and volunteers recorded 96 pairs and a minimum of 49 chicks successfully fledged.

This is the highest number of chicks for this small seabird since 2020, making this a ‘good year’ for this characterful seabird which had previously been struggling due to predators such as foxes, rats and birds of prey.

It also faces the additional problems associated with high spring tides washing away nests and disturbances caused by people and dogs.

‘It’s always satisfying when you reach the end of the nesting season and you know a species has done well,’ says Duncan Halpin, National Trust Ranger at the site.

‘We are able to maintain a 24/7 presence on Blakeney Point throughout the breeding season thanks to our team of dedicated volunteers and employ a range of approaches to give Little terns and other shorebirds the best chance of breeding.’

‘We also set up a remote monitoring camera, which allowed us to keep an eye on the colony at all times of the day and night.’

‘This helped us keep track of how the birds were getting on, and what threats, such as rat and gull predation, and human disturbance, they were facing.’  


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