Another dividing line swishes by, another town holding a world of interesting diversions is avoided, another intriguing landscape is no more to us than a speculative conversation. The South Island is big. We’re only here for a week. Result: driving and lots of it! From the moment the ferry docked in Picton late on Wednesday afternoon, the progress has been relentless, first to Saint Arnaud that evening where we camped by Lake Rotoiti in the Nelson Lakes National Park. Then to near Westport the next morning where the first of our South Island sites was located.
And that’s when Plan A started to go a little awry. We’d planned to sample a site called Anderson’s Pakihi, but when we got there the fringing scrub was thick and in the most accessible part of the site the vegetation was not what we were looking for ... the wire rush was conspicuous by its absence. We found it on the far side of the site on some higher ground alongside a house, but behind a high deer fence. There was nobody at home so our access was again foiled. It’s always a little tricky to know what to do in these circumstances, but given our schedule a quick decision was needed. That decision saw us saying goodbye to Plan A and hello to our new friend, Plan B. So onwards we plodded south, this time towards our next site at Okarito, just north of Franz Josef Glacier.
We weren’t too worried about passing over Anderson’s Pakihi because in the North Island we had learned about an alternative site near Dunedin. The reason we’re on this crazy trip trying to cover so much ground in two weeks is because we want our samples to cover a gradient over the full range of different types of rainfall received across New Zealand. Rainfall, specifically the oxygen isotopes in rainfall, differs depending on where it has originated from. So rainfall in the north of New Zealand that comes more from the sub-tropics has a different isotopic signature to rainfall in the south that will generally be blown in on the Westerly winds. It’s these differences that are driving our site selection and as it turns out, the new site near Dunedin gives us greater variability than Anderson’s did. Amazing what you can learn on the ground that you can’t sat at a computer on the other side of the world!
So we put the new site, Swampy’s Summit, in our pockets for later in the week and headed to Okarito. Another three and a half hours on the road saw us get there late on Thursday, but with a few hours of light remaining, we decided to press on and get some South Island samples in the bag to boost morale. This we did with great efficiency as the late evening sun sunk towards the horizon and coloured the vegetation a deep golden brown. Okarito was by far the wettest site we had visited so far, again a good thing in terms of capturing a range of environments in our samples. Not such a good thing however for the comfort of my feet as I took a step on an innocent looking patch of ground only to disappear down to my thigh!
The next day was a mammoth road trip, about 600 km from Franz Josef Glacier down to Invercargill, but got us within firing distance of our penultimate site at Otautau. The sampling here went off without a hitch the following morning; a friendly local farmer was happy for us to use his track along to the edge of the bog, access was easy save the jumping of one ditch and the wire rush was abundant. Again it was a very peaceful spot, with the only sounds the calling of birds flitting around in the blue sky above and snowy mountains on the distant horizon. So with a spring in our step, we headed off towards Dunedin, ready to bag our sixth and final site and toast a successful trip.
And that’s where Plan B started to go a little awry. On a cold, blustery Sunday morning, we could be found walking up to Swampy’s Summit high above Dunedin, well wrapped up against the elements, climbing the last two kilometres along the dirt road past the locked gate that marked the edge of the scenic reserve. Clouds rose up the hill side and blew about us, from time to time obscuring the expansive views of the town and surrounding countryside laid out below us. We made the summit and found the bog. The wire rush, however, had once again decided on a disappearing act. We recognised plenty of the vegetation we were used to seeing on our previous sites but search as we might, there was none to be found. So it was with a sense of frustration that we retraced our steps and tried to decide what to do next.
The problem was, there were a lot of potential versions of Plan C. We could head back south or way up north in search of other sites, but neither was very practical either due to site access issues, further risk of missing wire rush or simply having too far to travel in too little time. In the end we decided on a Plan C that brought our fieldwork trip to a rather stuttering end; Rewi will sample another site in the North Island when he goes there in a couple of weeks for another project. So we’ll end up with our six sites and fingers crossed the results we need to test the hypotheses of our project, but not quite in the way we envisaged.
We always know travelling the length of New Zealand in such a short time would be a rush and indeed it proved to be just that, but worth every hectic minute. Personally it has been a wonderful learning experience and the chance to engage with the local iwi at Tangonge was a real privilege. As with most scientific projects, the real work begins when the samples arrive back at the lab in the UK. The hours of lab work and analysis is really where we earn our daily bread and I’ll post updates as the project develops to let you know how we are getting on. In the meantime, please get in touch if you have any questions.