Welcome to the third instalment of our work on the Shiant Isles Recovery Project from RSPB Scotland's Phil Taylor. The project is an initiative to remove non-native black rats from the isles in order to provide safe breeding sites for Scotland’s globally important seabird colonies. It is part funded by the EU LIFE+ programme and is a partnership between RSPB Scotland, Scottish Natural Heritage (SNH) and the Nicolson family, who have been the custodians of the Shiant Isles for three generations.
Shiants episode three: bedding in for the winter
RSPB Scotland is not known for shying away from a challenge, and the Shiant Isles Recovery Project is no exception.
The Shiant Isles are a set of three main islands between Skye and Harris, fortified by high cliffs and massive boulderfields and moated by six miles of the stormy Minch. They are one of our most important seabird colonies, 10% of the UK’s puffins breed there every year, along with a hundred thousand other seabirds (razorbills, guillemots, bonxies, fulmars and shags). Such is its importance that the site is designated as a Special Protection Area (SPA) and is protected by European law. However, they are also home to a population of non-native black rats which exist across each of the three main Shiant Isles (and possibly the adjacent sea stacks, which are well within swimming distance). Studies of the stomach contents of rats and role in the food chain suggest that the animals are consuming seabird eggs and chicks on the islands. They are also thought to be the reason that Manx shearwater and storm petrels are not breeding on the islands.
Seabirds on the Shiants (video by Phil Taylor)
Island eradications are not something which we conservationists are quick to jump to. However, the RSPB has led a handful of eradication operations over recent years and has seen significant recoveries in seabird populations following; in the ten years since black and brown rats were eradicated from Lundy numbers of breeding Manx shearwaters increased ten-fold, and on St Agnes and Gugh in the Scillies Manx shearwater successfully fledged chicks immediately after the rats were removed, with storm petrels following two years later.
The Shiants project was first thought about in 2008 when an RSPB study showed that the islands were the highest priority seabird colony to be restored for Manx shearwater and storm petrels. In the six years that followed, we have been collecting and considering the evidence around the islands, the seabirds and the rats, ultimately taking the decision, in consultation with SNH and the islands’ owners, that an eradication would provide benefits to both the SPA and to the potential for Manxies and stormies. With support from Tom Nicolson, SNH and with European Union LIFE+ Nature funding we therefore began a project to eradicate the rats from the islands in October last year.
We have spent this year studying the islands’ ecosystem and creating a baseline to monitor how the islands change and, although the islands’ ecology this year has been hugely influenced by the wet weather, have already found some interesting trends and relationships.
The eradication itself will happen this winter, when the rat population is at its lowest, and I have just returned from helping the team from setting up ready for what is going to be a very challenging six months.
Although RSPB experience in eradications is building and will be built yet further by the Shiants project, the sheer complexity of running an operation on the islands meant that we have sought expert advice in leading the eradication. Kiwi experts Wildlife Management International (WMIL) have been recruited to lead the work on the islands. We have been working closely with them and learning from the expert guidance of Biz Bell and her team.
The first stage of the set up was to establish two camps for the winter teams to live in. Whilst Garbh Eilean and Eilean na Tighe (Rough and House Islands) are connected by a causeway, and therefore can both be accessed by a team living in and around the bothy on Eilean na Tighe, Eilean Mhuire (Mary’s Island) is separated by 500m of treacherous sea and therefore needed its own separate living quarters. This accommodation was provided in the form of Expadacabins, flatpack sheds we helicoptered in from Harris. We started on Mary, where the ground was uneven and the learning curve steep.
Setting to with the world’s largest spirit level Robin quickly overcame the uneven ground but, as with any flat pack build, we all stood about for some time reading the instructions and trying to understand the diagrams. The first cabin took around three hours to build and more than a little brute force. Meanwhile we took delivery of a couple of tons of bait, a few hundred bait stations, and four thousand stock cubes. Four quarter ton concrete blocks had been brought in to anchor the cabin down, something very necessary on Mary, where the geography allowed very little natural shelter.
Helicopter dropping off supplies (video by Phil Taylor)
Almost as soon as we were done constructing the cabin on Mhuire, we all ran down to the boat to be shipped across to Garbh Eilean where the chopper had also delivered another two cabins in flatpack. By now the daylight was fading and so we raided the summer team’s remaining stores and settled down for dinner.
Day two was devoted to building these two cabins behind the bothy. By this time we knew the tricks of the trade and were actually able to build them both fairly rapidly – the third took just 47 minutes. As if we hadn’t had enough flat pack fun, we then also furnished one of the cabins with bunk beds, and the other with a fortress of bait buckets. Ever level headed, Robin also put together some perfectly flat decking.
Up goes a cabin! (Video by Phil Taylor)
On our final day another helicopter brought in the remaining food stores, bait, and a lot of coal. It also helped carry some of the heavy bait and equipment to caches on the top of Garbh Eilean to save everyone’s back later in the operation. By the time we left the camp was looking neat and robust, with everything lashed down and in its place - exactly what you need going into a winter in the Western Isles. We left only for a fortnight, but returned in strength. At the end of October we arrived on the islands with our colleagues, Jaclyn Pearson and Paul St Pierre from the Isles of Scilly Seabird Recovery Project and the full Wildlife Management team. This trip’s objective was to establish the bait station grid, including the rope access points. Luckily the weather for this trip was better than we even saw in the summer; we were able to make full use of the shortening days and do so without several layers of thermals.
Whilst the rope team investigated the cliffs, deciding which ledges needed visiting and which were too unsafe to have been accessed, the rest of us chased Kelvin from Wildlife Management, around the islands. He was setting up a grid of canes throughout the islands indicating where the bait stations need to be placed to effectively be accessed by rats.
The bait stations, though a fairly basic design, provide an important service. They are made of short drainage tubing, with an access hole and a spare piece of tubing used as a lid to allow baits to be placed around the islands in a way that can only be accessed by rats, out of the way of the gulls or sheep or other birds. Several hundred of these bait stations were carried around the islands and wired into the ground to stop them being blown away.
A bait station (photo by Phil Taylor)
I have spent a lot of time on the islands now, but this took me to places I’d not visited before and gave an interesting perspective on how the rats must have been using the islands. We haven’t ever recorded rats on the Galtachan, the sea stacks off Garbh Eilean, but given they are well within rat swimming distance leaving them untreated is too great a risk to the project. On a calm day we took a trip across. They are a magical spot, the tides tear through the gaps between and the soil underfoot crumbles and falls away because of the burrows dug in the summer, now vacant until next year. We placed around 30 stations through the chain.
Having done a shift as the human Stenna Stairlift, I left the team on the islands to head back to my other duties. Although this project is a real challenge, and will undoubtedly become more challenging as our days’ shorten and our weather becomes stormier, I was disappointed to be leaving and miss out on seeing the islands through the winter. These islands are a special place, and though the work can be tough at times, protecting and recovering them is always rewarding.
The team will be working on rotation for the next six months, two weeks on, one week off. Those on Mary will be sheltered in the single cabin through the winter’s storms. These are the people protecting our seabirds. I know you’ll join me in wishing them luck.