The tītī – the muttonbird – is the
sooty shearwater that still darkens the skies above the Foveaux Strait each autumn, migrating from the Arctic to the Antarctic, touching New Zealand only to nest in burrows on remote islands. It is a marvel of endurance – a small, dark torpedo that lives on the wind and the waves. Now imagine it bigger. Heavier. Slower on the ground but more powerful in the air. That was the giant shearwater, and it was the phantom of the coast.
Size and colonial intensity made it special. Shearwaters are seabirds that spend most of their lives at sea, returning to land only to breed. They nest in burrows – deep tunnels dug into soft soil or sand dunes. They come ashore at night, under cover of darkness, to avoid predators. For millions of years, that worked. The giant shearwater, being larger, would have dug deeper burrows, laid larger eggs, and raised bigger chicks. Its colonies would have been louder, smellier, more chaotic than anything that remains today.
It did the same things shearwaters do everywhere – but on a grander scale. It flew hundreds of kilometres out to sea to catch fish, squid, and krill. It skimmed the waves on stiff wings, tilting and banking, using the wind to cover vast distances with almost no effort. It returned to its burrow at night, regurgitated oily fish paste to its single chick, and then turned around and flew back to sea. It was a machine of oceanic efficiency.
Slowly. Shearwaters are long-lived – decades – and lay only one egg per year. The chick takes months to fledge. A giant shearwater would have taken even longer, investing more energy into each offspring. That strategy works when the colony is safe. It fails catastrophically when rats arrive.
Rats and humans destroyed it. The kiore (Pacific rat) arrived with Polynesian settlers around 1300 AD. Rats climb. Rats swim. Rats dig. They found the shearwater burrows – thousands of them, each containing a single egg or a helpless chick – and they ate everything. A rat can wipe out an entire colony in a single season. The adult birds, evolved to fear the darkness but not the ground, were helpless. They could fly. Their chicks could not. Māori also hunted shearwaters – as they still hunt
tītī today – for food and oil. The giant shearwater, being larger, would have been a prized catch. A few centuries of hunting, combined with relentless rat predation, and the giant was gone.
The
sooty shearwater survived because it nests on small offshore islands that rats reached later or not at all. The giant shearwater, which may have nested on the mainland, had no such refuge.
Today, the
tītī still flies. But it is smaller. Quieter. Its colonies are fewer, its burrows emptier. And somewhere, on a windswept headland that used to shake with the cackling of giants, there is only the sound of the wind and the sea – and the phantom that used to own the night.