Isolated from its closest neighbour Auckland Island 660 km of wild, deep Southern Ocean, the last landfall before Antarctica, Macquarie Island is a wildlife refuge like no other.
Despite its tiny size and extreme topography, the island supports a thriving populous of Elephant Seals, Fur Seals, Royal, King, Gentoo and Rockhopper Penguins, Wandering Albatross and Giant Petrels, as well as numerous other seabirds and marine animals. With no land, nowhere to breed, for 5000 kms to the east and west, seals haul out to give birth and mate on the island and non-breeding visitors rest from their endless swim. Seabirds fly thousands of kilometres to nest and rear their young on the plateau and rock stacks. Countless generations of penguins have thronged the beaches, raising chicks who inevitably gravitate back to their birthplace to continue the family line.
Four species of penguins nest on Macquarie Island, with numerous colonies on the northern and eastern beaches and even up in the caves and tussock grasses on the beach terraces. Over 2 million birds land on the island each year to breed and raise their young.
Royal Penguins Eudyptes schlegeli are endemic to Macquarie Island, and although closely related to Macaroni penguins only breed on Macquarie Island and have a distinctive white chin. Like most penguins, Royal Penguins share the parenting of their young and feed mainly on fish, squid and small crustaceans. Royal Penguins are by far the most numerous birds on Macquarie Island, with an estimated population of over 850,000 breeding pairs. Despite their large concentration on the island, the Royal Penguin is currently listed as Vulnerable to Extinction under the International Union for Conservation of Nature (IUCN) Red List due to its restricted breeding habits – any threats to the island are a direct threat to the penguin population.
King Penguins Aptenodytes patagonicus were heavily harvested for oil in the 19th century, but thankfully the species has recovered well on Macquarie Island and there is a substantial breeding population that is still increasing in size. They look very similar to, and are closely related to the ice-dwelling Emperor penguin of Antarctica. King Penguins breed on a number of Subantarctic islands, and their diet consists mainly of lantern fish. King Penguin chicks do not fledge in the first year, spending the winter on Macquarie Island with their parents returning from their own winter feeding grounds to keep the chick nourished. Like other penguins, King penguins go through an annual ‘catastrophic molt’, replacing all their feathers over a short period. A penguin will feed heavily at sea then stay on land for up to 3 weeks until the molt has finished. King penguins are listed as a species ‘of least concern’ by the IUCN, which means it is not facing serious threats and is expected to keep thriving in the Southern Ocean.
Gentoo Penguins Pygoscelis papua spend all year on Macquarie Island, feeding not too far offshore and returning to land nearly every day. They are deep divers, able to plunge up to 200 meters below the surface in pursuit of prey. Rock cod, squid and amphipods make up most of their diet, all of which are abundant in the deep Macquarie Trench, just offshore from the island. Gentoos prefer ice-free areas, especially for nesting. They build their nest out of grass, feathers and other materials, rather than brooding their eggs on their feet like King Penguins. They are one of the most widely distributed penguins and can be found around the Southern Ocean. The subspecies Pygoscelis papua ellsworthii prefers a colder environment and breeds as far south as the Antarctic Peninsular.
Rockhopper Penguins Eudyptes chrysocome are the smallest crested penguin, only reaching a diminutive 50 cm in height. Their name describes their movements on land – hopping and bouncing across uneven rocky Subantarctic island beaches and nesting grounds, rather than waddling. Like all penguins, their powerful streamlined wings are superbly effective flippers for propelling them through the water in pursuit of prey, or away from predators. Rockhopper penguins breed on a number of Subantarctic islands and have been declining throughout their range in recent years – it’s not currently known why. The main suspect is a warming ocean, caused by climate change. This affects the penguins’ food sources – mostly small crustaceans – and also their breeding behaviour. This drop in Rockhopper numbers has resulted in the species being listed as Vulnerable to Extinction by the IUCN.
Like all birds, penguins have unique calls. This website has links where you can listen to the calls of different species of penguin.
Southern Elephant Seal Mirunga leonina. Towering over thousands of penguins, the Elephant Seal is impossible to miss. Males can weigh in at up to 3000kg, with the biggest males called Beachmasters. They are named after the male’s large proboscis which is used to vocalise their presence and ward off breeding competitors.
Watch a fierce breeding battle between two Beachmasters on this video.
Elephant Seals haul out on the island in September, males coming ashore first. Females come ashore several weeks later to give birth and suckle their pups, then mate again before heading out to sea to feed through winter. Elephant Seals head south from Macquarie Island for winter, feeding on squid and fish along the ice shelves of Antarctica. They have amazing biological adaptions to their blood and muscle that allow them to dive over 1500m deep, and stay submerged for up to two hours. Elephant Seals were targeted by sealing gangs throughout the 19th century for their rich blubber, but made a good recovery after sealing was banned. It has been noticed in recent decades that their numbers are dropping, but the cause is unknown. Some factors could be the increase in competition for food from other seal species, or effects of climate change. Despite this, Elephant Seals are listed as a species ‘of least concern’ by the IUCN, which is hopeful for the seals’ future.
Three other species of seal breed on Macquarie Island: the endangered Sub-antarctic fur seal Arctocephalus tropicalis, the Antarctic fur seal Arctocephalus gazelle and the New Zealand fur seal Arctocephalus fosteri. There was a thriving fur seal population on the island when it was first discovered in 1810, which was wiped out by 1820. It’s still not known what species of fur seal were on the island then, and if they were of a now extinct species. Fur seals began returning to the island in the 20th century, and now have established breeding grounds. There is some evidence that the three species of fur seals on Macquarie Island interbreed. A 2009 study looked at the possible causes and impacts of interbreeding, and suggested it may be a consequence of the ongoing impacts from the age of sealing.
Seals and penguins are the most visible wildlife to a tourist in the island, but they represent only a few of the native animals that nest, breed and live in this isolated refuge. The plateau and rock stacks around the island are filled with nesting birds each spring and summer, from majestic albatrosses to tiny Fairy Prions. Over 30 bird species are known to breed on the island and another 60 are regular visitors.
Four species of albatross nest on the islands, the most abundant being the Light-mantled sooty albatross Phoebetria palpebrata, that nests on the steep tussock slopes going up from the beaches to the high plateau.
Grey-headed albatross Thalassarche chrysostoma and Black-browed albatross Thalassarche melanophrys both only breed at a small number of sites in the south west region of the island, including the Bishop and Clerk Islets.
Wandering albatross Diomedea exulans nest mainly on the islands plateau and breed every 2 years. Their long breeding cycle is thought to play a role in the dwindling numbers of this majestic bird, which is listed as Vulnerable to Extinction by the IUCN.
Albatrosses and many other seabirds spend years at sea on the open ocean, only returning to land to breed. Very little is known about their lives away from land, and there are research programs around the world looking to fill in the gaps in our knowledge like the Global Seabird Tracking Database. This global project is collating datapoints from around the world about seabirds and their distribution, combining information from over 120 research institutions.
Albatrosses and other large seabirds, like Giant Petrels, are seriously threatened by the thriving fishing industry in the Southern Ocean. The main threat comes from the practices of long-line and trawl fishing, where the birds are unwanted by-catch. Thousands of large seabirds die as by-catch each year, and the international community is taking steps to reduce this toll through the Agreement on the Conservation of Albatrosses and Petrels, which seeks to mitigate the threats to albatross and petrels from human activity, primarily from the fishing industry.
The Southern Giant Petrel Macronectes giganteus, and the Northern Giant Petrel Macronectes halli breed on Macquarie Island. Both species have declined significantly in recent decades, impacts from the fishing industry are thought to play a part.
Oher large birds that call Macquarie Island home include the fierce Subantarctic Skua Catharacta skua that scavenges carrion and preys on live small birds, and the no less voracious Kelp Gull Larus dominicanus, which has been known to eat its own eggs and chicks in times of need.
There is another endemic bird to be found on the island, a subspecies of the King shag Phalacrocorax albiventer purpurascens aka Leucocarbo atriceps purpurascens. This bird breeds only on Macquarie Island and is closely related to the striking Blue eyed cormorant Phalacrocorax atriceps.
The island’s biodiversity does not end with its large birds and mammals. Although no reptiles or amphibians have been recorded, there is a healthy terrestrial invertebrate community of approximately 300 species, with an estimated 10% thought to be endemic. These include a native land snail and two species of slugs. Fourteen nematode species have been recorded, and it appears that the freshwater invertebrates in the lakes and wetlands of the island can be found on other Subantarctic islands, indicating they likely travelled to the island on the legs, feet and feathers of migrating birds (Macquarie Island World Heritage Area Management Plan 2006).
Endemic invertebrates are not just found above sea level. In and beyond the islands tidal zones are rich and diverse communities of marine invertebrates including starfish, molluscs, sponges and amphipods, to name a few. Many of the species that have been identified so far appear to be endemic to Macquarie Island, especially molluscs. Dense swathes of kelp and algae, anchored in rocky substrate provide a comparatively sheltered environment from the ever-present West Wind Drift, or Antarctic Circumpolar Current. Surviving in this shelter from the inexorable current may play a role in the type species found here – the amphipods and isopods most commonly found in the waters around Macquarie Island do not go through a free-swimming larval stage, but brood their young instead. This would ensure more young survive and thrive in the sheltered environment around the island, rather than be washed out into the open ocean.
Any invertebrate young that do get washed out to sea would be quickly eaten by the fish and squid inhabiting the deep waters around the island. The Macquarie Trench is rich with marine life, providing nearly all the food required by the animal population of the island. Antarctic Toothfish, Patagonian Toothfish, Lantern fish and numerous species of Squid thrive in the cool, nutrient rich waters, and can escape the lines and nets of Macquarie Island Toothfish Fishery within the 12 nautical mile bounds of the Nature Reserve.
The largest predator in the Macquarie Island Nature Reserve is undoubtedly the Killer Whale Orcinus orca, or Orca. With a mouthful of sharp teeth, Orcas are top tier predators feeding on Elephant Seals, Fur Seals, large squid and even other whales. They are skilled and canny hunters, and often hunt in family groups, or pods, aided by excellent communication between individuals. Orca communication has been extensively studied, and it has been proposed that they even have local dialects. Orcas are found around the globe, from the poles to the tropics and while they do not have any natural predators, they are threatened by human activities like fishing and pollution. More information is needed to determine the health of the global Orca population, but it is hoped their adaptability will ensure their survival.
Macquarie Islands’ charismatic and abundant wildlife has been bringing people from across the globe to its shores for over 200 years. Until the early decades of the 20th century, seals and penguins were relentlessly harvested for oil and skins resulting in the extermination of fur seal colonies, and possibly an entire species. Scientific interest, and expeditions dedicated to studying the island, took off in the 20th century, followed by students and tourists keen to experience this unique natural wonder. Today, the island and its wildlife is protected by international, federal and state laws and agreements that ensure protection from exploitation and encourage both research and sustainable tourism, to better understand the amazing wildlife of Macquarie Island.