I’m crouching in a windowless stone cell, peering at a ball of fluff stuffed into a crack in the floor. The cell is a beehive hut, or clochán; 1,400 years ago, it offered sleeping quarters to monks. The fluff is a baby seabird – to be precise, the chick of a European storm petrel. As my eyes adjust, I make out the glint of a tiny eye. After dark, the parents will return with food. For now, the chick sits tight.

Storm petrels nest only on remote, uninhabited islands, so seeing a chick is a rare privilege. I give the bird its privacy and crawl back outside – gasping anew at my surroundings. I’m high on a vertiginous rock outcrop in the Atlantic, just south-west of Ireland’s south-west corner.

Around me are the drystone walls of an ancient settlement, inhabited by monks from the sixth to the 12th century, who subsisted on seabirds and hid from marauding Vikings. The sea far below me is a ridiculous blue, its wrinkled surface sparkling with a confetti of gannets.

This otherworldly location is Skellig Michael. To the monks who once prayed from its summits, it was the very edge of the known world. Today, Star Wars fans know the island’s rugged cliffs as Luke Skywalker’s sanctuary on the planet Ahch-To. Conservationists – perhaps more worried about our own galaxy – know it as one of Ireland’s two Unesco world heritage sites and, since April, as the jewel in the crown of Ireland’s first marine park.

The Kerry Seas national park (Páirc Náisiúnta na Mara, Ciarraí) encompasses 70,000 acres of precious marine and coastal habitats off Ireland’s gorgeous Kerry coast. It embraces numerous sites of rich cultural heritage and outstanding biodiversity. The latter includes internationally important seabird populations, plus everything from basking sharks and sunfish to dolphins and whales.

Guide Catherine Merrigan is very protective of the birds. It was the puffins that first brought her here 20 years ago: about 8,000 of them breed on Skellig Michael, though for my visit, in early September, they’re back out at sea. But she’s equally taken by the Manx shearwaters and especially loves the nocturnal calls of the storm petrels. “It’s a gorgeous noise – like a kind of techno-humming,” she says. “Not like the manxies: they’re awful!”

I’m here on a day trip with Skellig Coast Adventures (from €50 adult, €25 child for a 2½-hr tour). “You’re lucky – it’s a pet day,” announced the skipper’s mate, Ger O’Sullivan, noting the balmy conditions as the Celtic Victor struck out from the little harbour at Portmagee. Before reaching the island, we passed Little Skellig, home to Europe’s third-largest gannet colony. Thousands thronged the ledges, with thousands more circling the waves. “Two days ago, we found three humpback whales out here,” Ger told me. I scanned the horizon for spouts.

In truth, whales have dominated my thoughts since I arrived two days ago. Ireland’s south and west coasts have gained a reputation as a top whale-watching location, with both minke and fin whales regularly seen in summer, and autumn being peak season for humpbacks, their showier cousins. Sightings are as good as anywhere in the British Isles. But this is the sea: you can never order anything up.

To maximise my chances, I started my trip in Kinsale, just east of the marine park, where humpbacks often appear offshore. Conditions were choppy as I headed out with Carroll O’Donoghue of Kinsale Angling Charters (€55 for a half day). “It’s not ideal for whale-watching,” he told me, “but you never know.” He was right: no whales. Nonetheless, we found a pageant of seabirds, a pod of common dolphins and, to my amazement, a school of bluefin tuna – the huge fish ploughing after shoaling mackerel.

Further out, Carroll’s sonar screen also revealed something bigger than any whale: the wreck of the Lusitania. One of the world’s largest passenger ships was just 18km off Kinsale when, on 7 May 1915, it was sunk by a German U-boat with the loss of 1,197 lives. Carroll told me how once, while listening for whale song with a hydrophone, he picked up a clanging sound from the wreck. “A loose hatch,” he told me, “but it was pretty spooky.” Quite.

After Skellig Michael, I drive north around the stunning Kerry coastline to Dingle. Rough weather is keeping boats in the harbour today, but at the OceanWorld Aquarium I find a fine selection of local fauna. Among the blue lobsters, seahorses and octopuses is a loggerhead turtle named Molly, who washed up on a local beach with an injured flipper. It’s a reminder of just what surprises the sea can turn up.

That evening at Dick Mack’s bar brings an impromptu session, with guitars, a cello and a lusty chorus of regulars working through songs from Van Morrison to Oasis. In the morning, I drive out along the panoramic Dingle peninsula, with mist spilling over the mountains inland and cloud shadows scudding over a slate-and-silver sea. There are hidden coves, proud headlands and iron-age ruins – and as each bend unveils another fabulous Atlantic vista, I comb the horizon for whale spouts.

Just off the peninsula’s western tip lie the uninhabited Blasket Islands. And immediately opposite them, on the mainland, I find the Blasket Centre. Opened in 1994, this impressive facility tells the extraordinary stories of the community that once inhabited these remote outposts: their privations, their literature and, finally, their evacuation in 1954 with many emigrating to the US. “It’s in 50 years’ time that this place is going to be important,” says manager Lorcán Ó Cinnéide, explaining the centre’s mission to preserve and celebrate the islands’ natural and cultural heritage for future generations. He’s delighted that they now form part of the new park.

Late afternoon finds me just off Great Blasket, the largest island. The weather has improved, and I’m out with Brendan Curtin and Liz McCooey of Aqua Terra Boat Tours (tours from €50 adult, €35 child). As we rock in the swell, gazing up at the abandoned stone dwellings, an eerie wailing hangs on the breeze.

The lament of lost souls? In fact, it comes from the grey seals hauled out on the beach – maybe 150 of them. Others periscope through the surf to check us out.

We return over a silk-smooth sea, the evening sun gilding the basalt cliffs behind us. The light is perfect for spotting whale spouts, but nothing’s happening today. Except, suddenly, it is. Manx shearwaters sweep in, seemingly from nowhere. Kittiwakes join them, circling and dipping.

Ahead, the sea is detonating with diving gannets. Shoaling sprats, thinks Brendan. He heads for the action and, as he speeds up, dolphins join the frenzy, leaping and weaving at our bows. Suddenly, dead ahead, a long gleaming back, like a submarine. A minke whale! Not a humpback – not today – but still, a whale. There she blows! I don’t shout it – but I want to.

The trip was provided by Tourism Ireland, with car hire from Hertz. The Royal Valentia Hotel has rooms from £120BB; the Dingle Skellig Hotel has rooms from £158 BB; the Blue Haven, Kinsale, has rooms from £129 BB