Buried treasure
Buried treasure
The threat to Niue's most precious asset (4 minute preview, 8 minutes full article)
The island of Niue is so remote that wherever on the coast you stand, the sea stretches unbroken to the distant horizon. It could be the clearest of clear days and you would see nothing but ocean. When I was there, at times the water was shaded a deep, almost unnatural, blue. Other times, it was grey, fading to a haze which blended with a cloudy sky. But it was almost always empty.
If you travelled north for 650 kilometres, you’d pass between some of the islands which make up American Samoa. If you travelled west for 430 kilometres, you’d pass between the islands which make up Tonga. To the east, you’d need to travel more than 700 kilometres before you reached the most remote of the Cook Islands, Palmerston. Travelling south, you’d miss the Chatham Islands by several hundred kilometres, and would eventually meet the Ross Ice Shelf.
I find it hard to imagine what the first arrivals must have thought when they found Niue. They would have known it was there before they saw it, because Polynesian navigators could find islands beyond the horizon by looking at the waves, as well as clouds and seabirds. But what did they think of it once they could see it? Were they disappointed about the lack of lagoon and beaches? Were they delighted by the size of the land area? Were they simply relieved to see solid ground?
If there was one thing they were hoping to find, it was surely water. But, at first glance, Niue doesn’t look promising. Although it’s not much smaller than Aotea/ Great Barrier Island, which has dozens of flowing streams, Niue has none. The coral rock is simply too porous.
The new arrivals would have had a tough search, but they probably knew what to look for based on their experience of their ancestors elsewhere in the Pacific. The rain which falls on Niue and other coral islands doesn’t simply run off into the ocean. It permeates down through the tiny holes in the rock until it meet seawater. But, because it’s less dense than the seawater, it doesn’t mix, but instead floats on top, forming what’s known as a freshwater lens, a buried treasure of cool, clear, lifegiving water. There’s a cave called Anapala where you can walk down over 150 steps and reach a pool of fresh water which used to be the water supply for a nearby village. (I’ve linked to a video here.) So there is water on islands such as Niue, but it’s neither abundant nor accessible.
Anapala was one of the places I would have loved to have visited on Niue, but it wasn’t a site which needed surveying for invasive weeds, so I never saw it. My travels on the island were dictated by where there were weed control programmes and where we might find newly arrived species. I did see some interesting spots, but they probably wouldn’t make it to the average guide book.
I spent one very hot day tracking back and forth across an area of shrubland which held the island’s only infestation of giant sensitive plant – which gets its name because the leaves fold up if you touch them. I couldn’t find a video of the exact species, but here is one showing a related, much smaller, species. It’s a fascinating plant, but it’s also a serious problem which has spread from its native range in Brazil to tropical areas worldwide. It forms thickets of scrambling, savagely-spined stems, and the seeds survive in the soil for years. There were no thickets left on Niue, but for some years the local staff had been checking the area every few months for new seedlings.
However, the recovery from Cyclone Heta had seen the time and energy of the island’s residents diverted to more urgent priorities, such as rebuilding the damaged infrastructure and reestablishing crops in fields which had been flattened. The site hadn’t been checked since the cyclone, so a group which included locals and the visiting weed survey team did a painstaking search. We found a number of small plants, and some were starting to form seed pods, so we pulled them out and bagged them before they could perpetuate the problem.
Another site we visited was an agricultural research station. There were all sorts of plants there, keeping the botanists of the group happy. Among the treasures was a thriving ylang-ylang vine. The flowers of this species can be used to produce an essential oil used for perfume. Although the plant we saw wasn’t flowering, there were fruit present, so there clearly had been flowers. To my knowledge, nobody on Niue is producing ylang-ylang commercially, but we also saw vanilla vines, and vanilla is exported from Niue. We also saw beehives – honey is another of Niue’s important exports.
Over the years, there had been many attempts to develop different agricultural industries on Niue, including cattle farming. I’m not sure whether this was beef or dairy farming, but I really hope it was beef, because an island with a scarce water supply and shallow soils over highly porous rock is just about the worst place I can imagine to put a dairy farm.
One crop which was showing signs of success was also one of the oldest on the island. The nonu, also known as noni and nono, depending on which Pacific Island you are on, is a large shrub related to coffee and New Zealand’s Coprosma. It’s thought to have originated in northern Australia and south-east Asia, but it was one of more than 60 plants sometimes carried by Polynesian explorers. In New Zealand, we are most familiar with the kūmara, because that’s the species which grew best in our temperate climate. However Polynesians also carried several different kinds of taro and yam, various tree fruits, sugar cane, gourds, timber trees, fibre plants and many more.