Rat's the way to do it

Maybe it's because of their location – out of sight, out of mind – but UK Overseas Territories (UKOTs) are often overlooked.   Thirty-three bird species on UKOTs are threatened with extinction – that's more than on the entire European continent – so I don't need to tell you how important they are.

Henderson Island is in the deepest depths of the South Pacific. It's a hotbed of biodiversity and has wildlife that's found nowhere else on Earth. It's one of the 14 UK Overseas Territories, meaning us lot over here are responsible for it.

For a long time now there's been a big problem blighting Henderson Island and all of its flora and fauna.  Typically it's a problem caused by us humans (aren't they always?) and that problem is rats.

Since they were introduced by Polynesian settlers the rats have been tucking into whatever wildlife they can get their teeth into.  Their favourite meal, it seems, is petrel chicks, including the endemic Henderson petrel. The little blighters feast on the chicks soon after they've hatched, and as rat numbers have dramatically increased, petrel numbers have plummeted, dropping from millions of pairs 800 years ago to just 40,000 now.

Picture credit: Richard Cuthbert

An eradication programme to rid the island of its rats and save the wildlife on Henderson has been mooted for a while now. Huge costs and complicated logistics were the main barriers, but we've been working hard to find solutions. Today I'm happy to be able to say it's going to happen this summer. In fact, the boat has already set sail!

Thanks to a unique international partnership and a generous contribution from the UK Government (Henderson Island is the UK's responsibility, after all, remember) we've been able to stop talking about it and start doing it.

This project has been close to heart of the Environment Secretary, Caroline Spelman, who announced funding for this project at Nagoya last year. She is continuing to support it, saying today: “Defra’s support for this important project proves our determination to protect endangered species, no matter where they are in the world. People introduced the rats which are threatening the survival of the Henderson petrel and now we’re trying to make amends before it’s too late.”

Sharing one set of equipment, two helicopters, a wealth of technical knowledge and an eager group of experts, the partnership will complete a three-island restoration project, covering 27,000km and reaching Henderson in August. Colleagues are referring to it as a 'voyage of conservation' – and I think that sums it up perfectly!

Once the rats are gone, we expect petrel numbers to increase quickly. But excitingly, it's not just the Henderson petrel that will benefit.  This is a full-scale island restoration and the whole ecosystem will be altered for the better.

Invertebrates, marine turtles and other birds that were either threatened by the rats or competed with them for food will begin to prosper once more. Plants and flowers – some of which can only be found on Henderson - will flourish with all the extra bird poo around to act as a fertiliser!

What's even more exciting is the prospect of what we might uncover following the removal of the rodents and after the island has begun to regenerate.  I’ve heard noises about the possibility of discovering stuff we didn't even know existed on Henderson. But we'll have to wait and see about that.

In the meantime we can look to two islands that went through the restoration process around 14 years ago – Oeno and Ducie.  Like Henderson, their petrel numbers were dwindling.  Just a handful of the birds were circling above while the rats below enjoyed tasty chick morsels on a far too regular basis.  Now, though, it’s a different story.  Find yourself lucky enough to be in one of these places, raise your eyes up and you'll be greeted by the sight of thousands of birds turning the skies black. The sight of success.

I hope the skies turn black above Henderson again one day, too.