By Bill Morris
In 2003 I was employed on Stewart Island as part of a group of commercial divers tasked with controlling the spread of the invasive seaweed undaria pinnatifida in those waters. For weeks on end, in biting southerly snow or summer sun, we would swim the lines at the Big Glory Bay mussel farms and examine every mooring, ship bottom and wharf in Paterson’s Inlet, Halfmoon Bay and Bluff harbour. If we found an undaria specimen, we’d carefully prise it off, trying to get every last piece of its root structure before destroying it. It was a war without end – every time we’d return to an infested site, there’d be more plants to collect. Undaria spores settle on a suitable substrate and germinate into gametophytes that can lie dormant, and therefore invisible, for years before sprouting into the delicate brown ribbons of the young undaria plant.
Undaria is a species of kelp native to the shores of Korea and Japan, where it is known as wakame and highly prized as a food. In Japan you might find it floating in your miso soup – the Japanese have long recognized its health benefits and have farmed it for hundreds of years. However, the algae has another less-endearing propensity – it is a ferociously successful marine invader. Undaria has a history of finding its way across the globe, establishing itself in the marine environments of other countries and easily shouldering out the native species. Within a few years, entire underwater environments can be changed – complex ecologies of sponges, algaes, and other marine life overtaken by a waving forest of the dark brown undaria fronds. The Global Invasive Species database lists undaria pinnafitida as one the 100 world’s worst invasive species. Undaria has no trouble moving around the sea – ships’ hulls provide a perfect substrate for the algae and vessels left stationary in an undaria-growing area will soon be trailing a brown lacy veil of undaria that will grow into bulky plants many metres in length if left unchecked. Undaria’s tiny spores can also be taken up in ballast water and carried across vast ocean distances.
It is believed this is how undaria arrived in New Zealand, where it was discovered in Wellington harbour in 1987. Since then, it has been accidentally carried around much of the coast and become well-established in a number of harbours from Gisborne to Stewart Island. In some places, like the Marlborough Sounds, undaria has displaced much of the native kelp and now clogs the reef systems. It causes a major headache for marine aquaculture as it binds up mussel lines and makes harvesting a much more difficult job. When I started working on Stewart island, the mussel farms in Big Glory Bay were free of almost entirely free of undaria. When the mussels were young, the lines were clean, white and held only the tiny mussel spat. As time went on the lines grew heavy and sagged deeper into the green-black gloom of the bay. The lines aged and foliated – native algaes, barnacles, sea squirts and sponges sprouted everywhere on the artificial reefs they provided, building leafy marine cities where little fish and crabs found refuge. One day, the aquaculture company imported a new batch of spat from the Marlborough Sounds – as soon as we dived in to give it its monthly check, we knew we had a major problem – the otherwise clean new lines were sprouting tiny undaria fronds everywhere. Those spat had been thoroughly checked and cleaned before being brought south, but the algae had resisted.
In 2004, the Department of Conservation abandoned its war on Stewart Island’s undaria infestation as too costly and ultimately futile. Today, the focus is on preventing its spread to other more remote corners of New Zealand’s waters, in particular Fiordland, the Chatham Islands and the sub-Antarctic Islands. This involves regular checks of boat hulls and underwater surveys of mooring lines and anchorages in those places. In 2010 a single undaria plant was found in Breaksea Sound in Fiordland. The relevant authorities have combined forces to stop it spreading from there – Fiordland’s utterly unique marine environment is at stake if they are unsuccessful. However, given undaria’s invasive proficiency, this too may prove to be a lost cause.
Since undaria established itself here, there have been calls from various parties to be allowed to harvest it commercially. It has been grown commercially in France since the early 1980’s after its accidental introduction there in 1971. Most of the demand for seaweed as a food source is in Asia, which is mostly able to meet its own demands. However, with New Zealand’s growing Asian population, a local market for fresh wakame does exist here. In addition, farmed seaweed has commercial value as a fertilizer and fish food and the hydrocolloids that can be extracted from the algae and find uses as gelling and thickening agents. Research has shown the heath benefits of eating seaweeds – they are rich in many minerals and antioxidants and may reduce cholestrol, boost immune systems and reduce joint pain. And so, just a few weeks ago, the Ministry of Agriculture and Fisheries announced it would lift the ban on commercial farming of undaria in three places – Wellington, Banks Peninsular and Marlborough. Operators will now be able to cultivate and harvest the algae in these areas, which are already infested with it.
Another fascinating possibility recently raised by US research is using genetically engineered microbes capable of metabolizing the sugars in seaweeds to create biofuel. Unlike land-grown biofuel crops like corn and sugar cane, seaweed cultivation does not take up valuable arable land and there is the potential to create huge amounts of clean fuel from a relatively small area of ocean.
Turning an invasive species into a commercial venture raises interesting questions around the philosophy of conservation in New Zealand. From my own experience with undaria I know the difficulties of stemming the onward rush of a invading species in a marine environment. On the land, pine trees and gorse can be controlled in small areas, but in general their steady march across our native landscapes continues largely unchecked. Rabbits, deer, pigs, possums, stoats and cats continue to ravage our grasslands and forests despite millions and millions of dollars and many years of effort spent fighting them. When deer numbers exploded out of control and their sheer numbers began causing immense damage to alpine and bush areas, government-paid cullers were hired to try and stem the tide, however ultimately it was a lucrative commercial industry for venison that was most successful in significantly reducing deer numbers. The experience with deer shows that commercial interests can have a positive impact in reducing pest numbers. Obviously in the case of undaria, commercial farming will do nothing to slow the spread of the algae around our coastlines – it is more about making the best of a bad situation.
The sheer volume of ocean, land and air traffic today means we are essentially powerless to stop the continued spread of plant and animal species from other parts of the world. But then species have always migrated around the world, even without the assistance of people. Long-distance dispersal has transported plants, birds and insects to many utterly remote islands. Natural environments, in biogeographical time-frames, are in a constant state of change and flux. The extent to which we try and halt this flow in our time is the dilemma our governments and the regulatory bodies charged with protecting our landscapes must face.
What are your thoughts?
By Bill Morris
Last weekend I headed over to South Westland to do some research for a TV show. I have spent quite a bit of time in the area between Haast and Jackson’s Bay over the last few years and always love returning there, no matter what the weather! Historically and scientifically, South Westland is a world apart from the rest of New Zealand. It is a fringe land – for most of its history beyond the reach of road and rail; a kingdom of rain and sandflies, greenstone, tumultuous rivers and long wild beaches shot with veins of gold-bearing black sand.
The people of South Westland are resilient pioneering types, many of who are descended from the area’s first pioneers and who have survived to make their home in this wild area.
South Westland is shaped first and foremost by the Alpine fault. The fault here is no abstract concept on a geological map, it is a highly visible battle line between two continental plates whose violence has thrown up the mountains that stand over the landscape and the lives of the people who live here. The mountains are what separates this land from the rest of the world, the mountains that provide the wealth of the region, mountains that make the rain and mountains that funnel that rain into the big, austere rivers that emerge out onto the coast.
During the Ice Age, this whole area was covered by an enormous glacier that emerged and merged from the separate valleys and would have reached the sea as one enormous wall of ice. Upon its retreat, six large rivers poured out of the mountains; scouring, sorting and carrying the crumbling debris from the interior. In the relatively fast (geologically-speaking) time span of just 6000 years, they built up the 10 kilometre-wide floodplain upon which the commerce and history of this region has largely unfolded.
The reason for the rapid advancement of the floodplain is simply the vast amount of material that pours out of the mountains here. The two biggest contributers of sediment are the Haast and Arawhata rivers, which between them produce over 13 million tones of suspended sediment each year, making them two of the most productive rivers in New Zealand.
Once this material has reached the coast, it is subject to the slow power of the sea, which shifts it north along the coast, forming long spits, bars and dune ridges. From the air, the remnants of old dune ridges are clearly visible and now form barriers that hold unusual patterned wetlands.
The floodplains today hold vast pakihi swamps and largely pristine native forest. The rainforest in this region is astonishingly rich. A couple of years ago, I made a video on the region with Emeritus Professor Sir Alan Mark and Katharine Dickinson in the area. Sir Alan, a tireless campaigner for New Zealand’s natural heritage, was instrumental in gaining UNESCO World Heritage status for the area which protects it from future exploitation.
Off shore, the Open Bay Islands are remnants of a limestone outcrop that survived the ancient glacier’s onslaught. Today they are a Maori-owned wildlife reserve, home to fur seals, muttonbirds, Fiordland crested penguins and an endemic species of skink. There is even a tiny population of endemic leeches on the island. The islands are the most species-rich pieces of land on the West Coast.
In 1810 a party of sealers were marooned on the Open Bay Islands for four years, and the remains of their hut can still be found there – the oldest European building relic in New Zealand.
South Westland is a fascinating and addictive area to explore. Check out my video for more insight thanks to one of the area’s greatest champion, Sir Alan Mark…..
…in which my travels in the sub-antarctic region of New Zealand continue.
After years of looking at pictures of remote Campbell Island, I was surprised to find it on arrival neither as cold nor as inhospitable as I had thought. Rather my impression was of a lush, rain and windswept landscape reminiscent of the South Island high country, only at sea level. Climbing off the zodiac at the wharf, we were immediately met by a harrumphing sea lion bull and a couple of rare Campbell Island teal. These endemic flightless ducks were thought to be extinct on Campbell Island until they were rediscovered living on tiny Dent Island in 1975. DOC has since done a lot of work to help the species recover, including a long-running breeding programme. Seen close-up, they are incredibly charming ducks – unafraid of people and possessing a sort of feathery meekness that is sort of irresistible. I’m an instant fan.
Flush with the awareness of actually being on Campbell Island, we tramp through tall, soaking poa tussock, past a pile of elephant seals slumped in a ditch who looked up sleepily at us. Elephant seals molt their fur during the summer and at this time they are vulnerable to the cold, so to conserve energy they find a comfortable spot and park up for a few weeks, often huddled together to keep warm.
Campbell Island is devoid of trees, save for one Sitka spruce, planted in 1907. With its nearest arboreal companion almost 200 miles away on the Auckland Islands, the spruce is now somewhat famous as the “loneliest tree in the world.” The most common tall foliage on the island is a thick tangled dracophyllum scrub, through which it would be almost impossible to pass were it not for the tracks that have been cut through it to give access to the distant corners of the island. Dracophyllum, whose Latin names translates as “dragon-leaf” and which is named for its prehistoric appearance, is common and widespread throughout New Zealand, Australia and New Caledonia. New Zealand has more than 30 varieties that range greatly in form from tall bushes to tiny cushion-plants. Research shows that the species most probably spread to New Zealand via wind-blown seeds long after the country had broken away from Gondwanaland. Upon arrival in New Zealand, the species initially found itself part of a very small gene-pool, thus mutations were common and the pressures of natural selection severe. In a relatively short time, therefore, the plant evolved in many different directions to fill a number of niches on the mainland and on offshore islands like Campbell, where it forms a kind on miniature forest across much of the island. It is believed the dracophyllum longifolium sub-species predominant on Campbell Island is only a relatively recent immigrant, arriving there by wind or sea around 7000 years ago.
Campbell Island is thought to have erupted from the sea 6-11 million years ago, so it’s probable that may of its species spread here via dispersal – travelling on the wind and ocean currents to fetch up on its remote shores. As in all of the subantarctic islands, many of the plant, insect and bird species here are endemic.
In 1894 Campbell Island was offered by the government for lease for sheep farming. In those days, high wool prices made such an option attractive, despite the 700 miles of ocean that separate Campbell Island from the nearest commercial port. Farming continued under various leases until 1929, when a slump in wool prices, coupled with a decrease in shipping access to the island made Campbell Island’s last farmer destitute. He returned to the mainland, leaving his 5000 sheep to wander the island for the next 60 years. The stock were progressively culled out and the last of them removed in 1992.
What followed in 2001 was an incredibly ambitious programme to eradicate rats from Campbell Island. The rats had been introduced sometime after 1810 and in the intervening decades had destroyed most of the native birdlife on the island. The programme involved four helicopters and 120 tons of poisoned bait and against the odds was a complete success. As a result, the island is now completely free of introduced animals.
Among the bird species that had been persecuted by rats was the Campbell Island snipe. (coenocrypha aucklandica perseverance) The snipe was not even known to exist until 1997 when a group of scientists searching for Campbell Island teal on the inhospitable, rat-free, finger of rock called Jaquemart Island discovered a few living there. The bird was named after the brig Perseverance that discovered Campbell island in 1810 and wrecked there in 1828. Ironically, it may have been the Perseverance that first brought the Norwegian rat to the island.
Since the rats have been eradicated, the snipe has recolonized the main island, and while still exceedingly rare, are now making a gradual comeback from the brink of extinction.
Stumbling through tussock, we were lucky enough to see one of these amusing and very friendly birds on the path ahead and I was able to snap this picture…
My travels of Campbell Island will continue in the next blog post….
A return to local broadcast for Dunedin’s esteemed natural history film company, NHNZ.
This film features incredible HD footage shot using the company’s ultra-fancy Phantom camera and tells the story of the unusual evolution of some of New Zealand’s most famous wildlife
Two foreign vessels fishing for the valuable Antarctic toothfish in the New-Zealand administered Ross Sea have met with trouble in recent months, sparking costly rescue missions and posing a real risk to the last untouched marine ecosystem on Earth.
Here’s the story so far ….
And for more information on the Ross Sea and the implications of fishing activity there, visit
Fighting our way around inquisitive/aggressive bull sea lions on the beach, we make our way to across Enderby island, walking through lush meadows of bulbinella rossii, which has just finished flowering.
On the northern side, tumultuous swells crash and break against the volcanic fringes of the island. It was on these jagged shores that the Derry Castle met her fate in 1877 – the seven survivors straggling to shore and surviving bitter hardships for several months. They broke into the castaway depot set up for just such an occasion, to find it contained only a bottle of salt, having been raided previously by a sealing gang.
Enderby Island is a pest-free haven for sub-Antarctic wildlife and every step brings new discovery – pipits and the occasional snipe scurrying about in the tall tussock grass; Auckland Island cormorants and Sooty albatross nesting together on a rugged, exposed cliff face, sea lions in tall grass and yellow-eyed penguins shuffling out of the sea and up across grassy slopes to seek refuge in the stunted rata forest.
To enter the Enderby rata forest is a special experience -like walking into a cool, green, woody cathedral, its floor littered with blood-red rata flowers amongst the sprawling mega-herbs. Sea lions enter the forest along with peguins, while Auckland Island tomtits flit amongst the branches.
Endemism is a recurring theme amongst the fauna in the se sub-Antarctic Islands. An endemic species is one which naturally occurs in one particular place exclusively. While many of the bird species on the Auckland Islands resemble their counterparts on the mainland, their long time in isolation has seen them evolve in subtly different directions. Consequently, birds like the Auckland Islands tomtit, the Auckland Islands cormorant and the Auckland Island flightless teal are considered separate sub-species that occur only on these wild islands.
The rate of evolution on islands has been shown to be very rapid compared to evolution on the mainland at least for a short initial period as species quickly evolve to accommodate environmental niches on islands that are different from those experienced by their mainland counterparts.
A common theme of island evolution amongst birds and insects is the loss of flight capability. Birds on islands usually lose the ability to fly because they are no longer being hunted by land-based mammals. The Auckland Islands teal is closely related to the Brown Teal endemic to the New Zealand mainland, but unlike that species, which retains some flight capability, both these two sub-species have completely lost the ability to fly. The Auckland Island teals appear to have taken that particular evolutionary path to its conclusion.
The Auckland Islands teal were once plentiful, but suffered the fate of flightess, ground-nesting birds everywhere with the introduction of mammalian predators. Thanks to the extermination of introduced pests, the species has now recovered to some degree on Enderby Island.
Over the next few weeks, I’ll be writing about my recent trip to some of New Zealand’s sub- Antarctic Islands with Heritage Expeditions. The first installment is in the Auckland Islands….
South! And it’s good to feel the sea rolling under me again. The Spirit of Enderby is bound for the Auckland Islands, 465 kilometres south of Bluff; lonely volcanic skeletons crumbling into the Southern Ocean – isolated snags in the furious 50’s, tiny specks of dry land between the mainland and Antarctica.
After two lively nights being thrown around by a good-sized westerly swell, the other passengers and I finally awoke to find ourselves in Port Ross at the northern end of the group. The Auckland Islands are the remnants of two large volcanoes that erupted from the Campbell plateau 10-25 million years ago. It is thought they were “hot-spot” eruptions, volcanoes that occur in a place where the continental plate is sliding across an unusually hot portion of the Earth’s mantle caused by massive plumes of magma that boil up from the Earth’s core.
(Other examples of hot-spot vulcanism are the Hawaii and Society Islands, including Tahiti. However research suggests that this explanation may not be true for all supposed “hot-spot” volcanos. Many mid-plate volcanoes, such as the Pitcairn Islands, may in fact be formed when the plate that hosts them begins tearing in the middle as a result of enormous friction along one of its edges.)
In the time since their eruption, the Auckland Islands have been heavily eroded by wind, rain and glaciers and the sea has gradually crept in to form long fiords and harbours in their sides. One of these harbours, Port Ross, separates Enderby Island to the north and it is to Enderby that we make our first landing of the trip at Sandy Bay.
The Auckland Islands have a long history of failed settlement, starting here on Enderby. Remnants of Polynesian cooking have been found at Sandy Bay indicating Maori explorers reached this far south in around 1200AD as part of the great Diaspora that saw them settle the New Zealand mainland. It’s incredible to think that people could find their way to this tiny speck of inhospitable land in this vast ocean so long ago – it also begs the question – why? With hundreds of thousands of hectares of relatively benign land to colonize, what drove these ancient navigators this far south? Were they forced off the mainland by hostile tribes, or was it simply the desire to keep exploring beyond the limits of the known world? We will probably never know, just as we will never know who exactly these people were and what eventually happened to them.
Another group of Maori, exiled from the Chatham Islands found their way here in 1842 and were later incorporated in the Enderby Settlement in 1849. This settlement was an ill-concieved attempt by a well-known British whaling firm to set up a whaling station and agricultural base that only lasted a few years until a lack of whales, ill-discipline and the harsh weather conditions forced its closure. There were two subsequent attempts at farming sheep and cattle on the islands, both of which were abandoned after just a few years in the face of storms and poor growing conditions.
Today, the islands are empty of people, although the years of settlement have left their mark in terms of introduced pests. The main Auckland Island is crawling in pigs and cats that have had a major impact on the island’s flora and fauna. Bizarrely, however, despite numerous shipwrecks and years of habitation, rats, which have caused so much damage on the mainland and on other sub-Antarctic islands, never made it ashore on the Aucklands.
While the main island is still plagued by these animals, the much smaller Enderby Island is today pest-free. This is largely due to eradication programmes that have removed mice, as well as the rabbits and cattle which had been originally left there to provide a food source for castaways.
(The last Enderby island cow, which somehow escaped the bullets of the eradication team, was rescued by a team of rare breeds enthusiasts, taken back to New Zealand and made part of a Massey University cloning programme. Today a handful of these cattle, both cloned and naturally bred from a cloned ancestor, are all that’s left of what had evolved in isolation to become a unique breed of cow, well suited to the harsh conditions on Enderby.)
Our zodiacs run up onto Sandy Bay where we immediately find ourselves admidst hundreds of Hooker’s sea lions – this is the largest remaining breeding colony for these animals in the world. Piles of silky-gold females and wrinkled pups crowd the sand while the big, noisy males charge around, fighting and grunting amongst each other. Amidst it all, skuas and giant petrels skulk around looking for scraps of placenta to feed on. It is a scene of ritualistic chaos that has been played out here in the Auckland Islands for millions of years
The males are jostling for position among the females –the dominant bulls control harems of up to 15 females and seemingly spend most of their time fighting off challengers. For some, control of a harem may last only days or even hours as one false move sees them ousted by a stronger or smarter competitor. Female sea lions, which spend most of their lives pregnant, will mate and hold the fertilized egg dormant in their bodies for three months, before conceiving once they’ve had time to feed and fatten in preparation for the nine-month gestation of the next pup.
The large number of sea lions here is deceiving –this species is in real trouble. What we are witnessing here at Sandy Bay would once have been a common sight around New Zealand, but over 700 years of hunting have left the mainland almost totally devoid of breeding colonies. (A single female – affectionately known as “Mum” has recently started breeding in Otago)
Worringly, numbers of sea lions returning to breed at the Auckland Islands are steadily decreasing. A recent DOC report found that the major cause of the decline is most likely to be the impact of squid fishing in the area. Squid are a major food source for sea lions, and when fishing boats, (many foreign, but catching New Zealand quota,) rake the sea with their giant trawl nets, they not only deprive sea lions of a food source, but also catch a significant number of feeding animals as well. If unable to escape the trawl net, the sea lion will drown in it. Vessels are now required to use sea lion exclusion devices that provide an escape route for the trapped and frightened animal to escape the net. However, while this certainly allows more sea lions to escape, it is unclear whether they are able to do so without sustaining fatal injuries first. What is clear is that sea lion numbers in this, their most important breeding ground are dropping, while at another, smaller, colony on Campbell Island, they are not. The only relevant difference between the two locations is that the Auckland Islands hosts a squid fishery, while Campbell doesn’t.
Despite these findings and although the Department of Conservation has upgraded the status of these sea lions to Nationally Critically Endangered, the government is now proposing to lift an existing quota on accidental sea lion deaths for the fishery, thus removing any protection for the animals in favour of giving free rein to the multi-million dollar global squid industry.
Keep an eye for unfolding developments in the news.
Next week in this blog, I’ll take you on a walking tour of the incredible Enderby Island and introduce you to some of the locals.
This week I’ve been editing footage of Jay O’Callahan’s fascinating “Forged in the Stars” story from ScienceTeller 2011. “Forged in the Stars” is a story that encompasses the history of NASA’s space voyages, from the Apollo Moon Missions in the sixties to the present day.
Listening to Jay’s story makes you realize that as we scurry about our busy Earth-bound lives, most of us seldom take the time to gaze into the vastness of space, to reflect on the incomprehensible mystery of the universe and to think of the astonishing feats of exploration that have opened up our understanding of it.
As I write, the two Voyager probes, launched in 1977, are well into the fourth decade of their lonely sojourns across the solar system, now dutifully reporting from far beyond Pluto, where the influence of the Sun’s powerful magnetic field and solar winds finally begins to falter. And I thought my 1978 Ford Cortina was doing well to still be on the road! Ahead of the Voyager probes lies true space – the vast emptiness between star systems. Once they escape the heliosphere (which may be in a few months or a few years), we will for the first time be able to make physical observations of the universe and its physics, free from the Sun’s raging influence.
I vividly remember opening a National Geographic back in 2004 and being astonished at the incredible images being gathered from the twin Mars rovers Spirit and Opportunity. There in glossy color was a real alien landscape – a muddy brown sky and barren rocky ground that could have been one of Earth’s deserts – except that it was not even on this planet. The rovers were only expected to last a few months, but six years later Opportunity is still trundling its rocky way across Mars, still teaching us more and more. It has now travelled 34 kilometers across the planet and lasted 30 times longer than it was expected to. (Spirit got bogged in sand in 2009 and finally became unresponsive last year.)
Meanwhile, just a couple of weeks ago, a rocket blasted off from Cape Canaveral carrying the next generation of Martian explorer. The Curiosity rover is five times larger then Spirit and Opportunity and carries ten times more instruments. It’s scheduled to land on Mars in August 2012 and will begin assessing the planet for evidence of past or present life. Within the next two decades it is possible we will witness a manned mission to Mars and part of Curiosity’s job is to help prepare the way for that.
In March of 2011, the Messenger spacecraft successfully locked into orbit around Mercury – the first space probe to do so and in August, the Juno spacecraft was sent winging its way to Jupiter, around which it is planned to go into orbit in 2016.
Meanwhile, transmitting orbiters are in place around the Sun, Venus, Mars, Earth’s moon and Saturn and in 2015 the New Horizon will fly past Pluto and into the Kuiper belt – the huge, shadowy ring of asteroids that marks the outer fringes of our solar system.
Then of course, there are the failures – usually stunningly expensive ones; an inevitable reality of space exploration that Jay O’Callahan alluded to in his ScienceTeller SCITED talk. Japan’s PLANET-C probe was unsuccessful last year in going into orbit around Venus and instead headed off on an unplanned detour around the Sun. Mission controllers will now have to wait another six years before trying again. And in 2011 the ambitious Russian probe Phobos-Grunt, which had been intended to land on the Martian moon Phobos and then return to Earth with rock samples, failed to escape Earth’s orbit. Controllers have now lost contact with the spacecraft and it’s expected to crash to Earth again in January.
We live in exciting times – the exploration of space is a fast-paced action adventure; unfolding before our eyes.