Our new co-ordinator, Ngaire Wallen has returned from a visit to the Chatham Islands. In this piece, she draws parallels with some of the South Pacific’s most notable island sanctuaries. She writes: 

Quite by coincidence, I have spent quite a lot of the last 12 months island-hopping.  It started with a tramp up Hirakimatā on Aotea/Great Barrier, followed by Hauturu, Norfolk Island, Tasmania, and more recently, the Chatham Islands.  Consequently, I have been pondering on these separate enclaves that so capture our imagination.  Each has a human story overlaying and impacting on their unique natural environments. 

Aside from Tasmania, firmly Australasian, the rest of these islands are all part of the recently mapped Zealandia Continent, officially the 8th Continent, finally fully mapped a few weeks ago, in October 2023.  Zealandia is 94% submerged, and like Tasmania, broke from the Gondwana landmass some 65 million years ago. 

 

Norfolk Island coastline. Surrounded by deep blue ocean, the rocky cliffs provide habitat for seasonal seabirds during nesting. Many Norfolk pine trees remain, but much of the understorey forest has been removed to create pasture for cows, which have right of way across the island except for the main shopping centre.

All of the islands have been shaped by volcanic activity at some point in their creation. Volcanoes on Aotea and Tasmania were calming down around 8 million years ago.  Hauturu and Norfolk were subject to volcanic activity around the same time, ending some 2 ½ – 3 million years ago at around the same time as the Chathams and its submersed volcanoes were pushed to the surface.

Together with the New Zealand mainland, they all started out as part of Gondwanaland, busted up and moved off, settling down around 10,000 years ago when the sea level established at about what it is now.   This separated Tasmania from mainland Australia, and Aotea and Hauturu from mainland NZ.  Since then, it is the movement of people that has shaped these once-connected but now distant islands.

Tasmania/Trowunna was settled on foot by Aboriginal tribes around 35,000 years ago.  The Palawa people are estimated to have numbered between 3 – 15,000 when, after 8,000 years of isolation, the British arrived in 1803.  By 1835 only 400 Aboriginal people survived.  20% of Tasmania is protected by UNESCO Wilderness World Heritage classification, and another 40% is either National Park or Reserve. The forests of enormous gum trees are spectacular, with their rare and endangered birds very different from New Zealand species 

Norfolk Island was ‘found’ by Cook in 1774, and within 26 years, 40% of the vegetation had been cleared.  Only 5% remains undisturbed, mostly within a 460 hectare National Park surrounding the highest peaks.  Norfolk has very similar bird life and forest plants as New Zealand, but like all island inhabitants they take on their own distinct characteristics.  Their boobook owl was once the most rare bird in the world – just one breeding female.  Two male morepork were transferred from New Zealand, she bred with them both, and numbers continue to grow.  Norfolk is excellent for observing seabirds during the summer months when they nest on the rocky cliffs.  Phillip Island, 6 kms from Norfolk, is a National Park and after rabbit removal in 1986 is again a haven for migratory seabirds.

Te Whanga Lagoon – a huge 160 sq kms of water that dominates the shape of Rēkohu, the main Island. The small exit to the ocean is rumoured to have been cut to lower the water level and make more farmland.

The Chatham Islands have a resident population of 800ish people living primarily by fishing for crayfish and blue cod, and pastoral farming.  Local residents are active in revegetation projects and various conservation projects on both public and private land, including for the taiko or Chatham Islands petrel.   Pockets of bush remain, with DOC responsible for 16 different reserves of one type or another.  Both Moriori and Māori have made Treaty Settlements with the Crown. 

Most of the main island, Rēkohu / Wharekauri, (everything has both a Moriori and a Māori name, usually written Moriori first) was cleared of forest to create farmland.   Habitats on the island vary wildly, from the enormous Te Whanga lagoon which covers 160 sq km, to wind-blown brush cover, conical volcanic peaks that rise from arid-looking flats, small areas of akeake tree that somehow cling on (it is actually an olearia and nothing like ‘our’ akeake), vast paddocks of gorse, and equally vast paddocks of grass supporting cattle, sheep, numerous horses and a few wild cattle and pigs.  Tough environment.  Tough animals.  Resilient people.   

The conservation reserves are only a tiny portion of the land mass, as shown on the map.  Something to ponder on perhaps, to secure a future for the unique flora and fauna?

Just to the south is Pitt Island (Rangihaute/Rangiauria), 2nd largest of the group, largely cleared of it’s forest cover and currently home to 38 people.   Further south again are the much smaller South East (Rangatira/Hokorereora), 3rd largest, and Mangere (Maung’ Rē/Mangere) 4th largest islands, both uninhabited, both DOC reserves, where only permitted visitors can land.   

Perfect volcanic cones dotted across the northern part of Rēkohu. Submerged when they were active volcanoes, the land was thrust upwards about 3 million years ago.

Rangitira is only 2.18 sq kms in area but provides habitat for a staggering 66 species of birds.  Designated a reserve in 1954, the last farming stock was removed in 1961 and restoration began.  The NZ shore plover and Chatham petrel breed only here, and it is one of the refuges of the heroic black robin.  An assortment of endemic birds that are recognised as separate species to their mainland NZ relatives – oystercatcher, red-crowned parakeet, tomtit, shag, and tui move between islands.  Surprisingly, tui became extinct on Rēkohu in the 1990’s and have since been successfully translocated from Rangatira.

Mangere is smaller again, at 1.13 sq kms.  Just a big rock really, once cleared for farming, until purchased by the Crown in 1966 with stock finally removed in 1968.  It too provides habitat for the black robin and other rare species.

Closer to home, Aotea/Great Barrier Island has a population of some 850 people, many of whom support conservation projects on the island.  Ngāti Rehua Ngātiwai ki Aotea are the recognised mana whenua of the Island.  It is 60% managed by DOC, and provides habitat for some very rare birds – black petrels nest only on Aotea, while pateke, kakariki and NZ dotterels are among our endangered species that make their home there.

Remnants of what once covered the islands – akeake trees – we know them as olearia – cling on in the fierce winds, but not when left standing alone. The akeake is usually the dominant species in replanting projects.

Hauturu was designated a Nature Reserve in 1895, the highest level of protection afforded by law, “an action that saved much of its natural biodiversity from human exploitation, but led to the eviction of the mana whenua, Ngāti Manuhiri, in an act that caused lasting pain and deprivation.”  (Hauturu, pg 20).   A deed of settlement in 2011 saw ownership pass back to Ngāti Manuhiri, who then immediately gifted all but a 1.2 hectare reserve back to the Crown.  Hauturu is staffed by DOC.   The island is the only natural source population for hihi/stitchbird, and the only known nesting site for storm petrels.  It provides a safe haven for many species of other birds that have started to spread back to the mainland, such as bellbirds and kaka, or act as source populations for translocations to other safe havens, such as kakariki, or as part of national recovery programmes like the kakapo.

What do I conclude from all of this?  Islands provide an environment where differences become accentuated – plants and animals adapt to survive in what can be remote, harsh habitats.  It is no different for people.  We have used islands as exciting new places to make a future or as a prison from which there is no escape – it all depends which side of the bars you are on.  Tasmania, Norfolk, Chathams, Hauturu –  all have a history of conflict, loss, and redemption.  We have fought over them, we fight for them.  Perhaps it is something to do with their fiery birth from deep within the Earth.  

As refuges for rare and endangered species of birds and plants, we need to protect our island habitats as best we can.  The islands I have visited in the last 12 months are all separate now, but once they were part of an enormous whole.  We have lost sight of the “wholeness” of nature, overstating our importance while diminishing the species we share our environment with.   In her book, ‘Braiding Sweetgrass’, Environmental Biologist Robin Wall Kimmerer muses on the consequences of scientific language with regard to the environment, which “has serious consequences for public dialogue about the environment and therefore for real democracy, especially the democracy of all species.  For what good is knowing, unless it is coupled with caring?  Science gives us knowing, but caring comes from someplace else,” (pg 345).

Let’s start caring, now that we know.

 

Chathams Map showing land in private ownership, and the meagre areas of conservation land. Unlike New Zealand there is no Queen’s Chain so beaches are mostly private land and inaccessible.



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