Why are we worried about invasive species?

This week would have been Invasive Species Week. One invasive species which is of huge concern in Orkney is the stoat. Here Sam Ranscombe from the Orkney Native Wildlife Project explains why.

Orkney is an incredibly special place for wildlife and although Orkney’s land area is less than 1% of the UK, 30% of Orkney land is designated for wildlife. Orkney has 20-25% of the UK breeding population of hen harrier, the UK’s rarest bird of prey, and has 15% of the UK’s population of black guillemots (or tysties as they are locally known). 

 Female hen harrier by Andy Hay (rspb-images.com)

In the spring and summer months, Orkney has the highest recorded density of breeding curlew in the UK and last but not least, the Orkney vole, an endemic sub-species of vole found nowhere else in the world. Wildlife tourism here is a vital support to local businesses and the economy, with half of tourist visits made to experience wildlife. 

 Red-throated diver by Chris Gomersall (rspb-images.com)

The Orkney Native Wildlife Project is a five-year conservation project started in 2019 as a partnership with RSPB Scotland, Scottish Natural Heritage and Orkney Islands Council with generous support from the National Lottery and the EU’s LIFE programme. Our aim is to promote Orkney’s unique and internationally important wildlife and protect it from the recent arrival of the invasive non-native species, the stoat. 

First reported in 2010, the arrival of stoats to Orkney poses a significant threat. Stoats are not native to Orkney and have no natural predators so are a particularly high risk invasive non-native species here. Feeding on small mammals, birds and eggs, stoats are a threat to Orkney’s native wildlife species including the Orkney vole, hen harrier, short-eared owl and other ground nesting birds, such as red-throated divers and waders like curlews, lapwing and snipe.

Stoat on a track with dead vole in its mouthStoat with vole

Elsewhere in the world, the introduction of stoats has had devastating impacts on island wildlife including in New Zealand where they are heavily implicated in the extinction of the bush wren, laughing owl, and New Zealand’s native thrush. We have a responsibility to ensure the same thing doesn’t happen in Orkney to our native species.

Our project aim is therefore to eradicate stoats from Orkney using trapping, to deliver biosecurity measures to prevent re-invasions and to enable local communities, tourism groups, farmers, land managers and schools to continue a legacy to protect native wildlife for the future.

 Lapwing on nest by Ian Francis

Currently the project is paused due to the COVID-19 pandemic, but removing stoats remains a priority and will help Orkney’s tourism business recover from this lost tourist season by ensuring Orkney’s native wildlife remain as a valuable and unique asset to the County. 

How to help protect Orkney’s native wildlife

If you are in Orkney we can report any stoats we see on the Stoats in Orkney Facebook page or by emailing stoatsightings@rspb.org.uk and as restrictions lift the project will have again have opportunities to volunteer including having traps on your land and helping with biosecurity on the outer islands.  Follow Orkney Native Wildlife Project Facebook or sign up for our regular blog for further information. 

And across the UK….

The UK-wide Invasive Species Week is run annually by the GB non-native species secretariat (NNSS) to raise awareness of the problems that invasive non-native plant and animal species cause in the UK when accidentally or deliberately introduced. Invasive species can cause harm to our health, way of life and economy but they also have a devastating effect on our native wildlife by feeding on them, out competing them for resources such as food or damaging the habitat they live in. 

 Water primrose. Credit GBNNSS.

There are ways we can all help reduce the spread of invasive species in the UK and there are tips and ideas on the GB NNSS website including identification sheets, free online training courses and activities for children. We can also report any non-native plants or animals seen from our homes or on our daily exercise, including species such as the water primrose, which takes over water bodies and can lead to flooding, or the Asian hornet, which predates on honeybees and other beneficial pollinators.   

 Asian hornet by Jean Haxaire.