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Thomas Mattern

University of Otago, Dunedin, New Zealand (Research Scientist)

La Trobe University, Melbourne, Australia (Honorary Research Fellow)

Global Penguin Society (Oceania Representative)

It was on a very cold, early morning sometime in the Austral winter 1993/94, that a young bloke from Germany sat in a small sea cave at Long Harry Beach, a tiny strip of sand on the northern coast of Stewart Island, New Zealand. After battling a muddy tramping track for almost a week in the hope of spotting a kiwi bird in the wild he wanted to get to the bottom of strange calls he had heard the night before. At the western end of the beach he had found a trail of odd tracks leading from the water’s edge up a narrow path to the top off the cliffs and into the bush. So here he was, looking out of his cave and over the glittering expanse of the Foveaux Strait, waiting.

With the first rays of sun the sandflies arrived fully intend on eating him alive. Suddenly he heard those calls again. And pretty close to his cave. He stopped swatting sandflies for fear of startling whatever might come walking past his hide-out. While the blood sucking insects had a party, four amazing little fellows appeared in front of the cave, craning their necks on top of their stubby, spindle shaped bodies to get a glimpse at whatever it could be that attracted such clouds of sandflies. The little fellows, walking upright almost perfectly mimicking a toddler’s gait, were Yellow-eyed penguins.

The view out of the cave at Long Harry (obviously taken with pre-digital photo gear)

The spectacle lasted but a few seconds, then the birds had reached the water and dived head first into the next wave disappearing from sight. Moments later, they reappeared, porpoising elegantly away from the coast until they were gone for good.

The young bloke kept staring at the ocean deep in thoughts. Why would a bunch of flightless birds jump voluntarily into an ocean full of sharks they could not fly away from? After years of watching penguins at the zoo or TV not thinking twice about their diving behaviour, he realized that there was something pretty strange about this concept. Pretty incomprehensible even. Once more he decided to get to the bottom of this.

Penguin Research

I did not know what a profound influence my first encounter with penguins in the wild would have on my life. Nor would I have guessed that I would return to the very same spot 15 years later to attach GPS dive loggers to the very same species – Yellow-eyed penguins – in an effort to reveal their secret marine life.

Counting more penguins in the Humboldt Penguin National Reserve, Chile than what were thought to be on the planet

I arrived there via a few detours. Keen to understand how penguins cope in their oceanic habitat, I studied the foraging ranges and dive behaviour of Little penguins using VHF telemetry for my MSc thesis with Prof Penguin Lloyd Davis at the University of Otago. A two year stint followed during which I worked with Ursula Ellenberg – my better half ever since – and Memo Luna Jorquera on Humboldt penguins (human disturbance impacts and demography) before coming back to Dunedin to do a PhD on Snares penguins. This time we deployed cutting-edge GPS dive loggers that hardly anyone had used before.

Taking a good look at Snares penguins (and vice versa)

The new technology also offered an opportunity to take a closer look at the foraging behaviour of Yellow-eyed penguins. Considering the amount of research that had been done on the species, we knew very little about that aspect of their biology. And after uncovering their principally benthic foraging strategy, and the effects seafloor alterations by fisheries can have on their foraging behaviour, I did come full circle – back to Stewart Island.

Since my last visits a lot had changed. There were hardly any penguins left at Long Harry or in fact, most of the north-eastern Stewart Island coast. And when we studied the penguins’ foraging behaviour it became clear that it’s not so much sharks they have to fear out at sea. We found that it was the destruction of their benthic habitat by dredge oyster fisheries which greatly reduces their prey diversity, and the accidental bycatch in set nets in Foveaux Strait that affect their reproductive success and survival rates, pushing the species ever closer to the brink. To this day I continue to work with Yellow-eyed penguins, most recently trialing camera loggers that will hopefully allow us to examine whether or not Yellow-eyed penguins have the behavioural flexibility to adapt to the alterations of their benthic habitat.

Being mainly based at the University of New Zealand (although currently Honorary Research Fellow at La Trobe University in Melbourne, Australia) has a significant advantage if it comes to studying penguins. There are so many of them around! Of the 18 or so penguin species six live and breed in New Zealand. And they all have adapted their own style of making their living in the ocean. And by studying their foraging ecology side-by-side we are slowly but surely getting closer to an understanding on the functioning of coastal marine ecosystems as a whole. So it makes sense to have a look at the fourth penguin species living in the subtropical waters around the New Zealand mainland – the Fiordland penguin or tawaki.

This is where we are now… just out of the starting blocks for the Tawaki Project (, twitter: @TawakiProject) supported by the Global Penguin Society and collaborating with international penguin research veterans. Over the next few years we will examine the foraging ecology of Fiordland penguins across their limited range which features extremely diverse oceanic environments. And get more of the puzzle pieces that will help us to understand what makes New Zealand such a special place for seabirds in general and penguins in particular.

Thomas at his latest Fiordland penguin study site, Jackson Head, West Coast, New Zealand