This is my last blog wearing my RSPB hat and I have decided to look again at the impact that Invasive Non Native Species (INNS) are having on biodiversity in the UK and across the globe. This is one of the hidden killers of native wildlife-and a by-product of man’s ability to cross oceans and inadvertently transport species to new environments. Trade and carelessness have been the downfall of many island species already, and here in the UK many seabird colonies on remote islands no longer support sensitive species, because of the relatively recent arrival of American mink, rats, feral cats and even stoats and hedgehogs, which predate the hapless eggs and chicks of petrels, shearwaters and auks. This could all get much worse as we grapple with ‘free’ trade issues post Brexit. So please read on, and support efforts to maintain and enhance safeguards against further problems for wildlife caused by invasive non-natives.

Photo credit: Jim Richardson.

One of the things I love about nature is its variety. Species evolve together and this continual adaptation and counter-adaptation means one species can’t dominate all the others. This leaves plenty of species for us to enjoy!

But will this last forever? We’re constantly moving species from their native habitats to ones where they’d never naturally occur, to places where they haven’t co-evolved with the native species. This may not always matter if the non-native species don’t adapt to their new environments and can’t survive. But a number of non-native species always will survive and the really problematic ones are those that then go on to dominate their new locations.

These species are known as invasive non-natives. And they come to dominate when the native species haven’t evolved to compete against them for food, or even to protect themselves from being eaten by the invader. And by the same token, native species also often haven’t evolved to eat the invader. So without the natural population brake that competition and predation provide, the invader simply thrives, displacing many native species in the process.

This is a big problem. In fact invasive non-native species have contributed to over 60% of all recent global extinctions. They’re also currently the world’s second biggest driver of species extinctions and the second greatest threat to UNESCO Natural World Heritage Sites. In other words, invasive non-native species are something all nature lovers should care about. But what’s this got to do with Brexit?

Well, domestic laws to tackle the threat from invasive non-native species are poor and out-of-date across most of the UK. Scotland has the most recent and fit-for-purpose legislation, thanks to revisions that were made by the Scottish Parliament in 2011. But even Scotland’s modern legislation was written before the current EU standard, the EU’s ‘Regulation on Invasive Alien Species’ (IAS) was drawn up, and so is missing some of the vital elements that the Regulation provides for. This Regulation represents the best international law we currently have to protect our nature from invasive non-native species. The Westminster Government is to be congratulated on committing itself to retaining this law after Brexit, but how can this be achieved in practice? Many questions remained unanswered.

How will the regulation be made to work across all four countries of the UK without the co-ordinating function of the European Commission? How will the Government continue to co-operate with the EU on invasive non-native species surveillance and management? Will the Governments of the UK commit to regularly updating and refreshing the ‘black-list’ of banned invasive non-native species and will they manage to have a co-ordinated single list? Will the independent scrutiny and oversight of an expert scientific panel be maintained? Will the Governments of the UK commit to the essential, specific provisions necessary to protect the seabirds that nest on our wonderful offshore islands?

So one clear risk from Brexit is that we lose the strong provisions of the EU IAS Regulation. But are there any others?

Well, international trade is the most common way invasive non-native species move around the world - either when they’re traded, or inadvertently when they hitch a ride on other traded goods. Although the exact nature of our future international trading patterns remain unknown, it seems likely there will be some changes, with the risk of weaker controls than we have now. This means there’s potential for a whole new group of invasive non-native species to become established in the UK. So changing international trade is a clear risk to the UK. It may also be an opportunity.

Again, it’s not known exactly what future control we’ll have of our borders and customs. But we’re likely to have a greater control than we have now as an EU Member State. So, there’s a huge potential for the UK to become a world leader in biosecurity, for the UK to become a world leader in protecting our economy, and the environment that underpins it, from invasive non-native species. And in economic terms we shouldn’t forget that invasive non-native species already impose a burden to the tune of £1.7 billion annually, according to UK Government estimates.

Will the Governments of the UK realise and seize this opportunity? Will we start to see the resources needed to protect ourselves and the UK’s nature from the threat of invasive non-native species? Only time will tell, but you can be sure the RSPB and its partners will be working hard to make the necessary safeguards a reality.

If you are interested in non-native species and the work being done to tackle this problem, check out the RSPB's Shiant Isles Recovery Project, which is being carried out in partnership with SNH and the Nicolson family here.