“We don’t really think about it. We’ve always felt quite independent as a band,” Stornoway’s frontman Brian Briggs tells me. I’ve asked him whether they relish being different. It’s not often you go backstage to find a band playing hacky sack, dressed in some of the most fetching bird-based jumpers I’ve seen this year. It’s also not often you hear a band like Stornoway, who blend folk instrumentation with pop melodies and lyrics about hiking, saltmarshes and being the beta-male.

“I think we’re quite honest with the songwriting about who we are and we don’t pretend to be rock stars because we’re not,” he says. “In terms of our lives and what we’re like as people there’s no massive egos in the band or anything. So that comes through I guess. There’s this honesty to it, but also a sense of fun about it. We don’t take ourselves too seriously. I think that diversity of moods comes through in the album.”

He’s talking about their latest record Bonxie, which shot into the top 20 the week it was released. It’s a record I was dubious about hearing. Their debut, Beachcomber’s Windowsill’s charm was its naivety, while the follow up Tales from Terra Firma chronicled Briggs’ marriage – about as mature a subject as it’s possible to explore. I just couldn’t place where they’d go next. Where do you go for inspiration once your love’s requited and the honeymoon’s over?

“The last record was definitely quite a personal one,” Briggs admits. “There was marriage and a bit of death. It was quite heavy really, and emotionally quite powerful. This one’s more outward looking and more open and diverse in terms of its subject matter. It’s a bit of a sunnier album and a bit of a simpler, fresher, poppier one.”

It’s also a record that fully explores a theme that’s been present in their music since the off: the great outdoors. Briggs has an Oxford University PhD in ornithology, something that’s reflected in the album’s incorporation of 20 different bird calls, using each one as an instrument in its own right.

“It’s pretty subtle and on a lot of the songs it’s really subtle. There’s a couple of moments where it’s much more obvious, but they’re only momentary and it doesn’t really have a big impact on the song. It’s just a bit of an atmosphere. Our thinking is just to try and help immerse the listener in the settings for those songs because a lot of them are set in the outdoors.

“It’s combining my two passions really, the natural world and music. Because my background is in wildlife conservation and I’ve been able to bring that in quite a lot with this album. Partly because of having moved to South Wales – somewhere a bit wilder than Oxford – to write it, but also because it seemed to fit with this slightly less personal focus, so I was able to feed more from the outdoors in terms of the inspiration for it all.”

And it doesn’t end there, they’ve just announced three intimate gigs in RSPB sanctuaries where Briggs tells me he’s hoping for some “real birdsong in the background”. It seems strange, then, that the 20 calls weren’t part of the record from the start, but were rather added at a later date behind the back of producer Gil Norton (Pixies, Foo Fighters). “The bird thing? We had to put that on after he’d gone”, Briggs laughs. “I don’t think he’d have been too into the idea.”

The result is an album that feels vast and spacious. From opener Between the Saltmarsh and the Sea (“it’s kind of like With or Without You but without Bono,” Briggs claims, “we’ve replaced Bono with a marshy brain-like habitat.”), through flawless pop gem Get Low, to the stunning Road You Didn’t Take and modern-day sea shanty Josephine. I was wrong to be dubious, it’s arguably their best work yet. And they’re fast becoming one of the most consistently brilliant bands around.