Chatham Islands- New Zealand’s Wildest Outpost

800 kilometres to the east of New Zealand lie the Chatham Islands. There are 11 main islands in the Chatham Archipelago. Once joined to mainland New Zealand, these ancient islands are the final landmass in the South Pacific Ocean before Chile. They might as well be the edge of the world. The Chatham Islands are a life raft for those creatures that fall off the New Zealand mainland. Brought here by the prevailing currents, castaways cling on and adapt to their new home. They're a familiar bunch, yet unique. For those who are poor swimmers or flyers, the Chathams might be a prison. But for those who make their living following the currents of the featureless South Pacific, the Chatham Islands are a paradise. Over the course of a summer, easterly currents will transport a new generation of colonists to these shores. Locals will use every trick in the book to get a free meal. And a family of tyrants will fight to maintain their rule over the island's skies. It's the beginning of summer in the Chatham Islands. The days are growing longer and the waters warmer. Chatham Island is the biggest of all the islands in the archipelago. And in its underwater neighbourhood are many familiar faces. Blue cod, kina, paua and crayfish. But what sets this neighbourhood apart from New Zealand is that many of these creatures are descended from refugees. Brought here by a force beyond their control. Their journey, or their ancestors' journey, began 800 kilometres away. Off mainland New Zealand, a clump of kelp drifts off the South Island's Banks Peninsula. It has attracted a group of baby hapuku, which use it for shelter and food. But what the hapuku babies don't know is that their floating home is caught in a current on a one-way trip into the empty South Pacific Ocean. Unless they chance upon the only piece of land between New Zealand and South America. Some creatures don't arrive in the Chathams by chance. They choose to come here. Every summer, great white sharks flock to what has become one of New Zealand's hotspots. The sharks converge on a group of islands known as the Star Keys. And for good reason. These barren rocks host the largest fur seal rookery in the Chathams. Like the kelp raft castaways, the original seals were probably swept here by the currents. But there's little reason for them to return to the mainland. These are some of the richest fishing grounds in New Zealand. But while the seals might be quite at home here now, the great white sharks spend winter in the tropics and return to the Chatham Islands in summer. They've been satellite tracked as they travel here in a dead straight line all the way from Tonga. How great whites navigate so precisely is one of their most intriguing mysteries. At the start of summer, the male fur seal's breeding territories are well-defined on the Star Keys. This bull has claimed the rock pool as his own. Only females from his harem can relax here. In a seal colony, however, there is always another male willing to challenge. The pool bully sends a clear message to newly arriving males. This pool is mine. Underwater, blue cod play the role of bully. The job of chief bully changes from moment to moment in this community. An empty shell is worth investigating. And it becomes a battle for possession. The fight is an endless scrum, and anything edible left in the shell is consumed. Nearby, herds of kina and massive beds of paua graze on seaweed and algae. These Chatham Island paua beds provide a glimpse of what South Island reefs might have looked like 50 years ago. Both paua and kina make good eating for blue cod. So they've developed strategies to stay safe. Kina have no brain, but display creativity as they cover themselves with anything available to stay hidden. Around the paua beds, the cunning shellfish have a range of tactics to outsmart their blue cod predators. On the edge of the Chatham's archipelago lies Rangitira Island. This special sanctuary is one of a few islands anywhere in the world which has always remained pest-free. The island is covered by a canopy of thick, scrubby forest, which is a haven for some of New Zealand's rarest birds. It's likely ancestors of these birds were stranded here after storms. And unable to return to the mainland, many evolved into their own new species. Bigger tui, smaller snipes, and the rare black robin, which smashes his weta into bite-sized snacks. Still recognizable, but uniquely Chatham Islanders. Rangitira Island may be pest-free, but a tyrant rules the skies and shores here. And this little blue penguin's mate was on the menu. This is a brown skewer, the size of a small eagle, with audacity to match. These mates are two of 40, which patrol the rocky platforms on Rangitira's coast. They don't hunt fish like other seabirds. They are fundamentally scavengers and opportunists. And at this time of year, carcasses are numerous. Getting to the good bits sometimes requires teamwork. But the female, always slightly larger than the male, is not sharing. Around the sheer cliffs of Rangitira Island, numerous seabirds make their homes. White-fronted terns fish close to shore, so it's just a short commute back to the nest, where chicks are waiting. Skewers prefer scavenging, but this nest is an easy target. The parent courageously defends her chicks, while the female skewer weighs up her options. Back at their lookout, she bonds with her mate. The breeding season is underway for this pair, and soon they will also have chicks to feed, which will raise the stakes on how much food they need to find. The Chatham Islands are like a giant salvage net, catching the creatures swept from the mainland by powerful ocean currents. These same currents also bring a great bounty to the islands. The southern current is rich in nutrients from Antarctica, while the northern current is full of minerals from the rivers of New Zealand. When these currents collide, and the ingredients mix, the water turns into liquid fertilizer. In summer, when the water warms, this mixing triggers New Zealand's largest plankton bloom. So huge, it's visible from space. The arrival of the plankton bloom turbocharges the food chain. Sootyshear waters and Buller's mollymauks nest here in their thousands, and spend their days filling their bellies. A pair of Buller's mollymauks catch a blue cod, but a bigger white-capped mollymauk claims the fish as its own. The water's surface might not be the safest place to sit, though. The great white sharks are always lurking, and always hungry. During the plankton bloom, the seabirds return to Rangitira Island every day with bellies full of food. And of course, the skewers are always ready to exploit any bird's mishap. It's the male's job to patrol the couple's territory. He stakes his claim with a territorial display, and then begins a foot patrol around the borders of his clifftop patch. This is the nest where his mate will lay their eggs any day now. Next door, the neighbours nesting on the rocky knoll have a different arrangement when it comes to their partnership. There's a male and a female. Some female skewers take multiple male partners, up to seven. This is just a threesome, so pretty ordinary by comparison. The third territory on this Rangitira hillside is inhabited by a lone female. Her mate or mates are currently absent, and she's been left incubating freshly laid eggs. One of the rocky knoll males has his eye on her. It's common for skewer to steal each other's eggs. The female calls in distress, and two males respond. The raider attacks again, and now the eggs are exposed. The raider circles back to claim his prize, but he's attacked by the two males. The female joins the aerial assault, and the threesome sees off their rival. Today there was safety in numbers, but in a skewer community, constant vigilance is the only way to keep all the nests safe. Every evening at dusk, peak hour begins on Rangitira island. Thousands of sooty shearwaters are the first to return from hunting at sea. A crash landing is the only way through the canopy. The shearwaters make a beeline to their burrows, where hungry chicks wait. Then the storm petrels arrive. Each night, thousands of them also have to crash through the canopy. If they can't escape, they'll die, and become an easy meal for scavenging skewers. Night vision cameras reveal what happens on the pitch black forest floor. Little blue penguins have their own obstacles down here. These young penguins are on the cusp of adulthood, but they've still got a few things to learn about the birds and the bees. The male knows how to begin the courtship ritual, but quickly runs out of moves. Chances are, these two won't be having any chicks this summer. This blue cod has good reason to look grumpy this morning. The sides of his face crawl with blood-sucking sea lice, so he starts his day attempting to dislodge the parasites. Next up is breakfast. He'd love some power, but they're clamped down tightly. However, the cod knows of another creature that can help him out. Starfish are skillful hunters, and their arms have the strength to break a power's grip on the rock. The target moves surprisingly fast on its muscular black foot, but the starfish's tiny tube feet propel it just as quickly. The power clings on with all its strength, but the combined force of hundreds of tube feet is stronger. The starfish breaks the power's hold. But its victory is short-lived. For the power, this is death by a thousand nips. Halfway between New Zealand and the Chatham Islands, a kelp raft drifts slowly eastwards. It's been 40 days since these baby hapuku were swept from the mainland. They've grown and look a little more like their parents now. Young hapuku can spend up to four years drifting on the currents, so long as their raft stays intact. They'll continue their journey. At the Chatham Islands, the currents circulate the plankton bloom, enticing hungry summer visitors. The largest of the visiting predators lurk around the star keys, honing in on the scent of the seals. It's as if they sense just what is occurring in the seal colony above. The population has almost doubled in the last week, as all this summer's pups are now born. Some seal pups congregate at the nursery pool. The braver ones try out swimming, while their mothers are at sea hunting. This female bonds with her weak old pup, which is completely dependent on her for food and protection. It's always right after giving birth that the females are ready to mate again. Suddenly, the pup is in danger of being squashed by the bull. Fur seals mate just once every season, and the male's hormones drive his aggression. However, it's when the female resists and bites the male's neck that he's provoked to complete fertilization. And she can reunite with her pup. Pilot whales are another visitor to the Chatham Islands during summer. Contrary to their name, these five-meter-long mammals are not whales, but dolphins. Their leader is the pilot, and wherever the pilot goes, the rest of the pod will follow. This pod's leader is also their matriarch, and every whale here is a descendant of the elder females. They've come to the Chathams to hunt arrow squid, but since they're nocturnal, the whales take the opportunity to rest. They sleep hanging vertically in the water, one eye open. Like all dolphins, only one side of their brain sleeps at a time, because they need to surface for air. Pilot whales are not the only Southern Ocean wanderers to regularly visit here. In the Chathams Archipelago, there's an isolated rock known as the Pyramid. 5,000 Chatham albatross converge here to breed over summer every year. Although they cruise from South Africa to Peru, the Pyramid is the only place in the world where Chatham albatross gather to breed. Sometimes, both parents will leave a chick alone while they hunt at sea. Not a wise choice, as this island has its own pair of resident skewers. A passing shadow excites the chick, though the neighbors ignore it. The skewer has spied the vulnerable chick. That was a close call. Both parents quickly position themselves in vigilant mode. All around the Pyramid, Chatham albatross mates share intimate bonding rituals. But sometimes, enough is enough. It's probably time to go fishing instead. Easier said than done on this steep incline. Over on Rangatira Island, tiny skewer chicks are also starting to hatch. These babies are born with attitude, which challenges skewer parenting skills. At the Clifftop Nest, there's always one parent watching over the offspring. However, these two chicks have been left alone, which isn't entirely unusual. Baby skewers hatch with their eyes open, covered and down, and ready to run. Birds like this are referred to as precocious. There is one place the skewer chick's parents could be. There's no fresh water on Rangatira Island, so skewer often take a short flight to Pit Island, about 20 minutes away. There's a freshwater stream here, which attracts skewer to carry out an unexpected ritual. It's a little-known fact that these ruthless scavengers are extremely fastidious about their cleanliness. As the skewer parents remove all traces of their gruesome lunch, their two chicks sit alone in the nest, vulnerable to danger from above. The Chatham Islands were named Reekohu by their Moriori discoverers, referring to their misty skies. This phenomenon results when warm currents meet cold waters. But the Chathams are infamous for a range of extreme weather, and sneaking in behind the clouds of mist comes a storm from the south. The residents must batten down the hatches. Fur seals race back to their land-based colony. Kinna crawl to their home scars, a pocket in the rock carved by the movement of the kinna's own spines, and crayfish hunker down in their crevices. The swells bring with them all the flotsam of the ocean, including a raft of bladder kelp. The next morning reveals the damage from the storm. The huge, shallow lagoon at the heart of Chatham Island has become a prison for a swarm of jellyfish, which were blown in at the height of the storm. The strength of the swells has also ripped power from their rocks, and now they're stranded. The cleanup crew arrives, ready for the feast. During the storm, one pilot whale was separated from her pod. Now she swims through the shallows, lost and confused. But the rest of her family might have suffered an even worse fate. Chatham Island is one of the most notorious places in New Zealand for pilot whale strandings. It's believed that the broad, shallow beaches disrupt the whale's sonar, which causes them to swim into water that's too shallow. The lost female hears a familiar call. It's another member of her pod. Together, they follow the clicks and whistles towards the rest of the pod. The matriarch leads the whales to the safety of the open sea. For the skewers on Rangatira Island, the aftermath of the storm brings an extra bounty. Many seabirds were killed trying to land during the gale force winds. And now this is a scavenger's paradise. The clifftop nest parents take turns flying off to tuck into the windfall. And of course, they're not eating just to stuff their own bellies. The chicks are almost a week old now, and know exactly how to tell their parents they're hungry. Seems like it's time for dad to go stock up again. Meanwhile, the precocious little chicks rule the roost. The chicks won't fledge for another couple of months, but this little one is getting lots of practice in already. The male returns from topping up his resources, and the chicks are primed. Dad pre-digesting their food makes it easier for the chicks to eat. Dinner time at the skewer household is not for the squeamish. These chicks are fortunate to have such experienced parents taking care of their every need. Other chicks on Rangitira Island have not been so lucky. At Chatham Island, a raft of bladder kelp ends its rudderless journey. The crew of tiny colonists who came with it have dispersed now. But there's plenty of evidence of what their future may hold for them. Hapuku thrive in the Chatham Islands, and many of these adults likely made the same journey when they were babies. Down on the power beds, blue cod, as always, are on patrol. Seeking starfish they can rob, but this starfish isn't sharing. Blue cod have learned that when power are fleeing, they're at their most vulnerable. Sometimes it seems like a game for these well-fed blue cod. Eventually, the gang grabs a victim, and a food fight concludes the morning's work. The blue cod's antics attract attention. School sharks hunt unwary cod. This one has managed to get a bite out of someone, and now there's a scent of flesh in the water. That always attracts the biggest predator. He can taste the particles of food, but the sauce eludes him. Great white sharks are known for their blubber-rich diet of marine mammals. But this is not the whole story. The majority of their diet comes from fish and squid. Great white sharks are curious beasts, and often snap at anything. Seaweed isn't an option for a true carnivore, but cod are. This great white shark will just as happily settle for a nice fillet of fish. At the hilltop nest on Rangitira Island, the two skua siblings flourish with the devotion of both parents. Because the adults timed their breeding to match this time of plenty, no one will go hungry. Skua chicks learn early that bullying and coercion equals food. Skills that will serve them well in the future. Skuas might be the tyrants of the Chatham Islands, but the adults are remarkably tolerant when it comes to acting as the target for their chicks' life lessons. Elsewhere in their range, brown skuas rarely raise two babies. But here in the Chatham Islands, both chicks often survive to fledging. Thanks to the plankton bloom and the visitors it attracts, these chicks have had the best possible start in life. As summer draws to a close, the oceanic visitors begin to leave the islands. The pilot whales follow their matriarch out to sea. This is a society that truly values its elders. The old females share with their pod a lifetime of experience. And it's likely that regular returns to this unique corner of our big blue backyard will be passed down in their map for their future.