South Island
Māui's Canoe
The South Island of New Zealand has more than one name. It has, at various times, been called Te Waka a Māui, Māui's Canoe. It has also been called Te Waipounamu, The Waters of Greenstone, or Te Wāhi Pounamu, The Place of Greenstone. For a while the island was referred to as The Middle Island. And yet again it has been called New Munster.
However you call it, the South Island is separated from the North by the Cook Strait, which James Cook discovered in 1769. Abel Tasman may disagree and say that he discovered it in 1642, although he thought it was a bight (a broad bay) and not a navigable strait. Of course, they're both wrong. The Strait was discovered at the dawn of time by Kupe the Navigator, who chased Te Wheke-a-Muturangi, a giant octopus, across the strait, finally catching and killing it in Tory Channel. He then returned to Hawaiki and convinced others to join him on his next expedition.
There is much more to be said about Kupe, not all of it good. Even less of it meets with unanimous agreement. But the fact remains that the South Island has been inhabited by people for at least 800 years, as is evidenced by charcoal cave drawings at over 500 sites in the central region of the island. Some of these drawings are of creatures like the Moa, and we'll talk more about that later.
Prior to human habitation, during the last Ice Age, the North and South Islands were joined and there was no strait, Cook or otherwise. That is because sea levels were 120 meters lower then, which is about how deep the Cook Strait is. In fact, all of New Zealand, the Lord Howe and Norfolk Islands, New Caledonia and several smaller islands to the south all sit on a shelf that rises almost a mile above the sea floor. Since 2017 this shelf has been considered its own continent, even though it is 94% underwater. The continent of Zealandia is roughly half the size of Australia.
Now let's go much further back, long before the last ice age, to the Creataceous Period, 85 million years ago. We find that Zealandia, Australia, Antarctica, and all of the rest of the future continents are joined into the huge super continent Gondwanaland, and there is not even a Tasman Sea. At that time biota could flow freely across all continents, although all of the larger biota were dinosaurs.
Going forward in time now, by 70 MYA the continents begin to split up. Antarctica drifts south; the Antarctic Circumpolar Current starts up making Antarctica permanently frozen. Australia begins drifting north with a clockwise rotation; it is drifting so fast that when GPS technology is invented it will have trouble keeping up. And Zealandia drifts away from everything. And then it starts to sink.
By 20 MYA Zealandia is totally underwater. Any biota it had inherited from Gondwanaland has drowned. But then a curious thing happens. Zealandia is actually an Aulacogen - a place where the continental crust is being constantly created, destroyed, and rearranged. And the practical upshot of that is that after a period of sinking, there is a period of rising.
Over the next twenty million years, New Zealand becomes increasingly more and more above water. But it is so far away from any other land that the only things to be found here have blown in on the wind or the waves. So there are no snakes in New Zealand. There is only one indigenous mammal - a miniscule bat (although there are reports of a platypus-like creature the Māori call waitoreki). The bulk of the indigenous land animals are birds, although over the years, with no land predators, a lot of the birds have given up flying and live on the ground, growing larger in the process. And the largest of these was the Moa.
When people started arriving in New Zealand in the 14th century there were nine species of Moa, a very large flightless bird. The smallest species was about the size of a turkey; the largest species could forage 3.6 meters, or 12 feet, above ground and weighed a quarter of a tonne. Estimates of the Moa population prior to the arrival of people vary from as few as 58,000 to as many as two and a half million. Within two hundred years they were all extinct.
In fact, since the arrival of people, over 50 native species of flora and fauna have become extinct in New Zealand, partly due to pressures exterted directly by the people themselves and partly due to the pressures brought to bear by introduced pests, such as rats. Some indigenous species have learned to adapt to humans and their pests: a brown kiwi, for instance, will kick a stoat that is attempting to steal its eggs or chicks (although stoats still manage to kill 15,000, or six out of every ten, of North Island Brown Kiwi chicks every year). But a lot of New Zealand's indigenous critters are simply ill-equipped to deal with land based mamallian predators. Because there weren't any, until people started showing up, some eight hundred years ago.
The settling of New Zealand by both Polynesian and European populations tended to start in the north and progress south, and the disruption of indigenous species tends to be greater to the north and less to the south, and least of all on the uninhabited islands to the far south.
So that's a bit of the back story to New Zealand generally, and the South Island in particular. It's a little more rugged than the North. Possibly for that reason it was settled very slightly later than the North and, on average, less densely. While the South Island is quite a bit bigger than the North - it is in fact the world's 12th largest island - it is home to less than a quarter of the nation's inhabitants. And so therefore it has a little more authentic biota than the North.
Time to check it out.