Arriving at the penguin colony ten minutes early, I waited on the visitor centre's veranda. A man bounded up the steps and walked straight past me with a brief “G'day”. He tried the toilet door: it was locked. “That's no bloody good,” he said, racing towards a derelict shed. He never came back.

There's nobody here 'cept me and my penguin

There's nobody here 'cept me and my penguin

I spent a happy hour or so at the penguin colony. My guide, Georgie, took me to a cabin where visitors peer down tubes into dimly lit nests. It was quite something to stare at nesting penguins from such a close distance.

“Blue penguins are the smallest of all penguins. Unlike other species, they typically lay two eggs and most of them hatch,” Georgie explained. “Right now, we've got well over 200 eggs, and the first have already hatched. Males and females take it in turns to sit on the eggs during the hours of daylight: while one's out at sea, the other is here. That carries on until the chicks are two or three weeks old. After that, the chicks need so much food that both parents go to sea during the day to get food. You can hear the chicks greeting their parents as they get back in the evening – it's adorable!”

Penguin chicks grow incredibly quickly. They weigh about 45 grams when they hatch, rising to a kilogram within five weeks, the same weight as their parents.

There are actually two managed colonies of blue penguins in Oamaru, the one that's open to visitors and another in a wildlife reserve. Both have around 130 breeding pairs.

The story began after the harbourside quarry closed in the 1970s. A few penguins ventured ashore and burrowed under and around the abandoned machinery. They'd clearly decided this was a good place to create a new colony, away from the old stick in the muds they left further down the coast.

The biggest snag was the daily trip out to sea and home again: the quarry was on the other side of a track used by cars and lorries and a fair few got squashed.

There was a lively debate about the future of the quarry and the penguins that now called it home. At first, the Council wanted them out of there and even put up penguin-proof fencing. Finally, however, the matter was settled: the quarry was cleared of rusting machinery and set aside for the penguins. In 1997, a Penguin Protection Advisory Committee was established, and a visitor centre opened in 2001.

In the wildlife reserve, the penguins fend for themselves, making their own burrows and steering clear of tourists. In the managed colony, they get to live in purpose-built burrows. Each is a wooden box with an entrance tunnel angled upwards from the ground and then back down to the bare earth. Inside the box, the penguins do what comes naturally, digging a hollow in the ground. They line their nests with whatever they choose to drag in from outside.

The managed colony

The managed colony

Every box is monitored weekly and every penguin is tagged. Some are equipped with GPS monitors, which reveal that they travel around 50 kilometres a day during the breeding season, seeking out sprats which they partially digest and feed to the chicks back home.

When I first visited the colony five years ago, there was just one grandstand overlooking the rocks at the water's edge. At dusk, we watched groups of penguins – known as “rafts” - struggle up the rocks and line up on the side of the track before, at some invisible signal, scurrying to the safety of the quarry.

Today, there are two grandstands and the site has been reconfigured to be entirely penguin-friendly. The track has been diverted, which means the penguins get from the sea to the nest with no risk of being mown down by passing motorists.

Breeding and survival rates are more or less the same in the managed colony and in the wildlife reserve, so being a tourist attraction doesn't seem to have caused any harm to the penguins' prospects. That's just as well, because visitor numbers have risen to around 75,000 a year and are set to rise even further in the years to come. In fact, it's Oamaru's top attraction.

Georgie left me to wander round the site at my own pace. I read every word of every panel and loved every rain-soaked moment of it, apart from the bit about what happens to the newly-fledged chicks. They get eaten, God damn it. Or they starve to death. Or they get lost at sea and drown. The survival rate is around 30% in the first year.

Later, I asked Georgie about that. “The thing is,” she explained, “the chicks spend their whole early lives being fed in a nice warm burrow until one day it's time to go to sea. Their parents don't show them what to do or how to hunt: once they're out there, they're on their own. Some don't get the hang of feeding themselves. Others get snapped up by seals, sea lions or even sharks.” A bit of a bugger, really.

Those that do survive have to find somewhere to live. Breeding pairs nest in the same place year after year, and if they avoid being eaten, they typically live six or seven years. That means the vacancy rate in established colonies isn't all that high and penguins have to find new places to live - which explains how the quarry colony started in the first place.

Some displaced penguins find their way into other colonies around New Zealand. One ambitious penguin even got as far as Wellington, New Zealand's capital city, where she now works in a vegan cafe. Others look for nesting places closer to home, leading to sightings round the shoreline and warnings to check under parked cars and porches first thing in the morning. One pair of penguins is currently raising a brood at the back of a wool store in Harbour Street. Others have been seen brazenly walking around the Victorian precinct after dark, staring at strangers.

Before leaving, I went back to the viewing shed and peered at the brooding parents. I breathed in the heady aroma of penguin shit, which reminded me of chicken sheds back home. One of the simple pleasures of life.

On my way out, I thanked Georgie profusely and asked how long she'd been in her job. “About a year. I studied tourism at university but somehow ended up working in a bank. It was OK, but after seven years I found it – well, not boring exactly ...”

“Repetitive?” I suggested.

“Yeah, that's it. Same customers, same transactions, same conversations. I just fancied a change. I went to the UK and Ireland for a while and when I got back, I saw this advertised and knew I had to go for it.”

“You don't find this a bit repetitive, too?” I asked. “Tours on the hour, every hour; same commentary, same questions from the visitors?”

“No, actually. It's different from one tour to the next, and it changes with the seasons too.” She paused. “And there are penguins. What could be better?”

These penguin boxes are hidden in plain sight somewhere near the harbour ...

These penguin boxes are hidden in plain sight somewhere near the harbour ...