Kerry: Tides of Time - how I made the epic new RTÉ documentary

RTÉ News​

28-04-2025

Filmmaker Katrina Costello introduces her new documentary series Kerry: Tides of Time, narrated by Brendan Gleeson, which tells the multi-dimensional story of the Kerry landscape, from its earliest origins, deep in the geological past, right up to the present day - watch it now via RTÉ Player.
Making Kerry: Tides of Time has been one of the most challenging and rewarding projects I've worked on.
Like all my films, it began with a dream and a deep connection to people and place. Kerry's landscapes are striking, but I wanted to go beyond the postcard views, to spend time in the less-seen corners: the Atlantic rainforests, the mountain valleys, pockets of native woodland, and the bogs. These are the places where nature still clings on, protected somewhat by their remoteness from people, grazers, and plantations.
There wasn't a grand plan at the start, just a love for wildness and for nature. And where in Ireland is wilder than Kerry? While it felt like a natural follow-on from my last RTÉ series, The Burren: Heart of Stone, this became its own story entirely.
The place is vast. Its ecosystems are heartbreakingly beautiful, and, at times, heartbreaking in their decline. Even in remote places, the signs of stress are there.
Filming always begins with knowledge and respect: for the people, the land, and the creatures we hope to film. That deepened by spending time with the various contributors, all of whom dedicate their lives to protecting all of the above. I'm just passing through their landscape, really.
Making documentary films like this isn't always glamorous. I've slid down muddy banks, pulled out ticks, been eaten alive by midges, and yes, I've ended up hip-deep in bog holes more than once.
But I've also witnessed moments of pure magic: harriers passing food mid-air, sea eagles circling with ravens, corrie lakes glowing with colour, puffins skimming the waves, and the ever-changing dance between cloud and mountain.
My favourite moments are the dawns. Words fail those hours. Whether cloaked in mist or blazing with light, they're always full of hope.
So much filming of nature happens in those liminal, golden hours. I'm lucky to own a campervan which allows me stay close to location. I can rise before the birds or wait for that perfect twilight. It's my lifeline. There's something about wild camping that stirs the imagination in ways nothing else does. You fall asleep and wake to the sights and sounds of the natural world.
There wasn't a grand plan at the start, just a love for wildness and for nature. And where in Ireland is wilder than Kerry?
Maybe it's the hush between night sounds, or the stars, hinting at stories older than memory. In those moments, wrapped in quiet and shadow, the line between reality and myth softens. You feel part of something far greater than yourself, and it's as if the land is aware of you. If you listen closely enough, it just might speak to you.
No wonder there were so many great storytellers before electricity and the virtual world took hold. When you live that close to nature, the stories almost tell themselves.
Scenes: Nature
Some scenes were trickier to film than others. I reckon I spent close to 1,000 hours trying to film the hen harriers, one of Ireland's most endangered birds. Their numbers continue to drop, mainly due to habitat loss from large-scale spruce plantations.
We spent months with the red deer in the Kerry mountains, witnessing both the rut and the birthing season. There were endless dawns and dusks at badger setts too. We became familiar with each other, I think. As with all wildlife filming, you have to slow down. You wait. You watch. You listen. Often, I wouldn't film what I set out to, but I always came back with something. It might be a dewdrop trembling on a blade of grass, a surprise storm rolling in, or a new way of seeing an old place.
Working in bogs took some adjustment. Carrying a full kit, camera, tripod, long lens, across unstable ground meant many missteps, literally. Over time, I developed a kind of sixth sense: where to step, how to move, how to balance.
Technically, the setup was demanding. The kit I usually use weighs about 15-17 kilos, not including batteries, weather gear, or spares. It was physically tough, yes, but worth every ache for the quality of the footage.
Kerry: Tides of Time isn't just a film about scenery. I wanted to reflect on how we've shaped these places, how they continue to shape us, and what we might still protect. From overgrazed hillsides to the Skelligs during nesting season, the pressures on the land are real. But so is the hope.
I met incredible people doing vital work: Padraig O'Sullivan and the National Park rangers, individuals like Tim and Barry O'Donoghue, Eoghan Daltun, Aidan Walsh, Mary Reynolds and all of our contributors and many others involved in organic farming and rewilding.
There are fantastic community efforts too: the Meitheals clearing invasive rhododendron, the Maharees Conservation Association, Ballybunion Nature Group, and Home Tree, working to restore native forests. Their passion has left a lasting impression on me.
Sound and music were crucial
Composer Bradley Ayres created a score that held the visuals gently, letting them breathe. And Dunquin native Muireann Nic Amhlaoibh brought something otherworldly to the series. Her voice gave scenes a haunting, ancient quality, evoking a sense of wonder where words fell short.
So how did I approach this project? With commitment, careful planning, and a lot of time on the ground. It was physically exhausting, sometimes frustrating, and often slow. But more than anything, it was deeply rewarding. To spend that kind of time in one landscape, to watch it shift with the seasons, to learn its moods, and to be part of it, is a rare gift.
Kerry: Tides of Time is a tribute to the natural heritage of this place. But more than that, it's an invitation, to look again, to understand more deeply, and maybe, just maybe, to care enough to protect what we still have.