Guest blog: In this week’s blog we welcome Emily Williams, Senior Marine Policy Officer with RSPB Cymru, who joined Biosecurity for LIFE in the Western Isles as part of her sabbatical this summer.

I sat in my office (aka. the spare bedroom) in March, planning my sabbatical. Two years on since the first lockdown, I had long been dreaming of far-away seabird islands.

When Biosecurity Officer, Sarah Lawrence showed me a map of a tiny dot (North Rona) dwarfed by the surrounding Atlantic, it ticked a lot of boxes! I jumped at the opportunity to join the Biosecurity for LIFE team for a week, at the end of June.

North Rona and Sula Sgeir SPA

Locating North Rona on the map

We were headed to the Western Isles. Lewis would be our base. From there, the hope was to visit some of the most remote islands in the United Kingdom, including the Flannan Isles, North Rona, and Sula Sgeir. Surveillance stations had been installed on these islands by Biosecurity for LIFE last year. Our plan was to locate them again and check for signs of invasive non-native mammalian predators. However, as the trip grew closer, our role became multi-purpose. The devastating impacts of Highly Pathogenic Avian Influenza (HPAI) on seabirds were now apparent. Given the vast distances (North Rona being over 70km from Lewis), it was unlikely anyone else would be heading there soon. Therefore, we were also tasked to undertake an HPAI assessment for NatureScot, which involved looking for and recording all moribund and dead seabirds as part of our work.

We needed a decent weather window to get out to and land on these far-flung islands, so endless checking of the weather forecast became the norm. An unsettled start to the week gave us a good amount of preparation time. We checked the incursion response hub in Stornoway and disinfected our equipment and footwear (we would be following strict HPAI protocols). Once everything was prepared to go, the team started my training early, with an introduction to the new biosecurity board game! This had been designed by school children, for use in education settings. After playing late into the evening, it was clear that trying to free islands from rats (or rat tokens), is not an easy task. Biosecurity is essential.


Playing the Biosecurity board game until late at night. Photo credit: Emily Williams

The Flannans!

On the morning of the 29th June, we gathered to board the SeaTrek boat to the Flannans. We were joined by Barvas Estate and NatureScot. After an hour and a half of horizon staring, we arrived at Eilean Mòr! Safely ashore, we started the climb up the island; pausing for breath in PPE layers whilst watching the puffins that greeted us. Then it was straight to work checking the surveillance stations for rodent sign.


Walking across the island in PPE. Photo credit: Emily Williams

Sarah checking a surveillance station. Photo credit: Emily Williams

Thankfully, we only found signs of rabbit in the surveillance stations (and on the outside). See if you can spot the rabbit chew marks below...

Picture6flannansrabbit chew

Surveillance station with rabbit chew marks. Photo credit: Emily Williams

Having checked all the surveillance stations, we also laid out some temporary tracking tunnels and camera traps around the lighthouse. Whilst we found no rat sign here in the stations, we had received a recent report of a potential rat sighting at this location. We deployed intensive surveillance equipment to increase the chance of detecting a rat if one were present.


A tracking tunnel set up by the Flannan Isles Lighthouse. This was laid against a wall, as rats prefer to run along linear boundaries. Photo credit: Emily Williams

Biosecurity checks complete, we were waiting for the boat when we spotted a fin in the water. One fin quickly became many, and we were treated to a spectacular show from at least 20 bottlenose dolphins. They continued to jump and play as we re-joined the vessel. It was a magical wildlife moment!

20220629 162827

Emily watching bottlenose dolphins. Photo credit: Sarah Lawrence

Having seen no obvious sign of HPAI on Eilean Mòr, we travelled the short distance over to Roaiream, to observe the gannet colony from the boat. We were apprehensive, not knowing what would await us given the sad situation at other gannet colonies around Scotland.


Sarah doing HPAI checks. A maximum of ten, spaced-out deceased gannets were counted across the colony. Photo credit: Emily Williams

We recorded 10 gannet carcasses among the colony – the probable impact of HPAI, although we were relieved not to find high numbers of casualties among this colony.


Emily and Connie watching the gannets overhead at Roaiream. Photo credit: Sarah Lawrence

North Rona and Sula Sgeir

The following day, we reconvened at the jetty to start our early morning trip up to North Rona and Sula Sgeir. We were joined by Barvas Estate, NatureScot, and North Rona’s grazier. A four-hour journey on the comfortable SeaTrek vessel, I marvelled at tales of how others had made this journey in harsher conditions.

A huge whirl of puffins greeted us on arrival. Overseeing all was a white-tailed eagle, perched atop the hill. A juvenile: it must have travelled some way to get there!

With our PPE back on and after landing safely on the island, we started searching for the biosecurity surveillance stations. It didn’t take long before we ran into North Rona’s resident sheep.


Sheep on North Rona. Photo credit: Emily Williams

Whilst one of the surveillance stations had disappeared on the island and needed replacing (fur in surrounding boxes suggested it had been dislodged by one of hundreds of grey seal pups born here in the winter), the other stations were in excellent condition. We found a small number of carcasses belonging to birds that may have been victims of avian influenza – including 4 great skuas (bonxies). Despite the small numbers, we were saddened to find the number of bonxie territories dramatically reduced since our 2021 visit to North Rona with the MarPAMM Seabirds Count team; a sign that avian influenza has passed through North Rona.

With over 20 surveillance stations checked and refreshed with new wax chew blocks, we returned to the boat and headed over to Sula Sgeir. Only Tom, Sarah, and Connie were to land on this densely populated seabird colony, to minimise disturbance. As they travelled over to check the surveillance stations, we sailed around the perimeter of the island, checking for signs of HPAI. We saw a couple of deceased gannets across the site, thus suggesting that HPAI had not so far had a severe impact at this colony. And what a stunning colony it was...

Sula Sgeir from the sea. Photo credit: Emily Williams

Sarah, Tom, and Connie re-boarded the boat an hour later and we were really pleased to hear that no rat sign had been found. So began our long journey back to Lewis. It was several hours before we would see land on the horizon again.

Wrapping up the week

Safely back from our travels, there were a few more things to do before we said farewell to the Western Isles. First and foremost, we needed to disinfect all equipment and footwear.

Tom and I disinfecting equipment. Photo credit: Sarah Lawrence

The next day, we were excited to visit Uig Gala Day, where we had kindly been offered a stall. We had a super time talking to the local community about biosecurity, playing the boardgame with children and eating the delicious cakes on sale! It was the perfect way to end a most memorable trip.


Biosecurity for LIFE stall at Uig Gala Day. Photo credit: Emily Williams

Many thanks to the Biosecurity for LIFE project team for having me! And thank you to SeaTrek for getting us to these fantastic islands. For more on North Rona, Sula Sgeir and the Flannans, why not explore the project’s previous blog articles?

Routine checks of the surveillance stations on North Rona, Sula Sgeir, and the Flannan Isles will be required long-term (in perpetuity!), as the threat posed by invasive non-native predators such as rats will continue to be a concern to breeding seabird populations forever. We’re keen to build a network of “regular” visitors to these islands, who may be willing to check the harmless wax blocks inside surveillance stations for signs of chew marks. If you have come across this blog in anticipation of a future trip to these islands, and you may be able to make a quick check of some surveillance stations while you’re passing – please get in touch and we can send you some instructions.



April 2023

Skomer Biosecurity Incursion Response

Guest blog: In this week's blog we welcome Lisa Morgan, Head of Islands and Marine Conservation at the Wildlife Trust of South and West Wales to talk about how they responded to a shipwreck on Skomer Island last December and the biosecurity risk this posed.

June 2022

How Biosecurity for LIFE is responding to the current avian influenza outbreak

Tragically, this year our seabirds are facing an unprecedented and widespread outbreak of Highly Pathogenic Avian Influenza (HPAI). The disease originated in poultry in Asia, passed into wild birds, and has led to multiple serious outbreaks, including the loss of 1/3 of the Solway wintering barnacle goose population last winter. A wide range of seabird species have been confirmed as infected and we are seeing large die offs of several species at their breeding colonies.

May 2022

From the edge of the world - biosecurity on St Kilda

Here we welcome Sue Loughran, St Kilda ranger with National Trust for Scotland to tell us about biosecurity ‘From the edge of the world’. In the last few weeks we have been working with Sarah Lawrence (Biosecurity for Life Project Officer) to improve our measures for the islands of St Kilda, but what does “biosecurity” actually mean? How do we carry it out? How can everybody play their part?