Collections / Field work
Field technicians working in environmental research are a special breed. Their unofficial job description says they need good science skills; observant and patient; able to work on their own and as part of a team; and happy to rough it through all sorts of good, not-so-good and downright horrible conditions. They’re a fit, keen bunch of blokes and blokesses … and have oodles of common sense ‘cos the bush and the mountains are dangerous places.
Being a Field Technician with Landcare Research presents the opportunity to work in many of New Zealand’s most beautiful and often remote locations. But it’s not just about finding the ultimate picnic spot. There is a lot of planning, preparation and logistics that must go on back in the office before a field team can head into the hills. Often field teams are a combination of Landcare Research staff, environmental contractors and / or university students. It is the role of field techs to organize staff, equipment and transport.
The first step is to ensure that they have all the equipment they will need for the project, check it, then double check it. After all, the whole purpose for any field trip is to collect data. To find that you’re missing an essential piece of equipment once you’re in the middle of nowhere, and the helicopter has flown away, could spell disaster for the project.
The second step is making sure that you have the right staff for the job, that they have the relevant experience and correct equipment. This is all too important when you’re working in the often harsh conditions of the New Zealand back country. Staff need to be self-reliant, able to navigate through unmarked country and difficult terrain, and deal with whatever the weather Gods throw at you.
The third and often hardest step is to get all the equipment and staff in the same place at the same time. To help manage all this effectively, each trip has a Field Team Leader whose job it is to make sure everything runs smoothly, to manage the work load, oversee contactors, check data quality and manage any field health and safety issues that may arise.
Research scientists may also spend many days working in the field and need plenty of stamina as well. However they generally do not work across such a wide range of science projects as the field techs do.
However, both the field techs and research scientists all agree on the following:
Best bits — Getting to work in the outdoors in wilderness areas that few others ever get to, helicopter flights through spectacular scenery, travelling around the country to work at many different sites, catching up with the techs from other sites.
Worst bits — Working in wet bush in the pouring rain. Working in areas with an over abundance of plants such as kekie, supplejack, bushlawyer and hookgrass.
Field work goes ahead, whatever the weather
Everyone's favourite sort of field trip ... smack in the middle of a cold weather bomb, as “wind, snow, horizontal sleet and hail, wind, rain, and wind wind wind. Scientist Grant Norbury says "a tough, experienced and fun group (James Smith, Dean Clarke, Morgan Coleman, Carlos Rouco, Lisa Daglish) made all the difference to getting field work done under such challenging conditions.” Field tech Dean Clarke provides a somewhat understated account of working in Macraes Flat in Spring:
“Carlos and I set off from Dunedin hoping that the fierce southerly weather that was thrashing Invercargill wouldn’t spill over the Maungatua’s and hit the Macraes Flat field site. For those who don’t know Macraes Flat it is wide open tussock and farm country situated just north of Dunedin between the Rock and Pillar Range and the eastern seaboard. The only protection you get from the unrelenting winds and inclement weather is from the characteristic rock tors that dot the landscape, or by sheltering down behind your quad bike. It is also the site of the last strong hold for the Grand and Otago skinks that are managed by a determined bunch of Department of Conservation people based up there, with whom we stay.
“For this trip to Macraes (as part of IMI Drylands research), the team had to set up 48 grids, spread over 4000 hectares, designed to track and index common lizards, rodents, cats, weta and rabbits across landscape.
“Six of us working in pairs took five days to complete the work but as the photos show, conditions were less than ideal. One morning we woke up to find that the southerly had indeed spilt over and left us with 3 inches of fresh dry snow, perfect for skiing if one was so inclined. Alas with no ski mobiles, we did what all field techs do when confined to base camp: we drank tea and paced like caged lions. A game of scrabble also helped pass the time waiting for enough snow to melt to enable us to get back out there.
“Each day we faced very strong winds, snow flurries, rain, hail, mud, sleet and more wind which created a challenging work environment with one team spending half an hour digging through a snow drift just to get through a gate!
“Overall the trip was a great success due to the long hours put in by the skilled and experienced crew. On the last day, we were even rewarded by the weather gods with a mostly wind free and sunny day!”
From Spain to Central Otago
Carlos Rouco Zufiaurre is investigating possum ecology in dryland ecosystems
Since arriving from Spain last January, Carlos has been working with Grant Norbury, James Smith, Roger Pech and Andrea Byrom studying possums in Central Otago to improve knowledge of the ecology of possums in dryland ecosystems such as grass/shrub habitats of Central Otago. Using ‘capture, mark and recapture’ techniques, the researchers have concluded that possums are abundant in this ecosystem, especially in areas of greater shrub cover.
Carlos says “We have also been monitoring the movements of 15 possums with GPS-collars during Spring and Winter of this year, obtaining interesting results about denning behaviour and night activity. We are about to embark on a larger study, funded by the Animal Health Board, to gain a more detailed understanding of habitat use by possums in southern South Island habitats, and to determine where surviving possums (and TB) aggregate after control. Our findings will increase the efficiency and effectiveness of ground control of possums in dryland habitats.
“Alexandra is 19,000 km from my hometown Seville. Spain is almost the antipodes of New Zealand so I couldn’t be any further from home! The actual habitat structure in Central Otago is not too different to what we could find in southern Spain. Unfortunately the winter down here is far from Seville’s average winter temperature of 11.5ºC!
“The presence of wild rabbits in my Otago study site reminds me of doing my PhD. Before coming to New Zealand, I worked for seven years trying to ensure the recovery of rabbit populations for endangered predators in Spain. So imagine how I felt last April when I saw the results of the Easter Bunny Hunt competition in Alexandra … 23,000 rabbits dead in one day! Despite such differences, the environment could not be better for our research and my experience in New Zealand has been very worthwhile.”
Impacts of wild horses
The Desert Road and the huge block of adjoining Crown land known popularly as “the Army Country” has long been famous for its somewhat controversial wild horses. In the late 1980s, when the horse controversy was beginning, Mark Smale and his colleagues from Landcare Research set up some permanent plots (the bread and butter work of plant ecologists).
On a recent occasion when the plots needed remeasuring, the Army was using the normal quicker route for live firing so alternative travel arrangements were needed. Exquisite autumn weather provided the opportunity for a stunning helicopter ride up the Rangitikei Gorge to the Batley Reserve, where the family kindly allowed us the use of their Lockwood bach while we remeasured cute little Round Bush (so small that the plots take up most of it) and the tussock grassland nearby. Sika deer, seen but mostly heard, were conspicuous in the manuka scrub towards the gorge and seemed to be doing more damage there than the horses.
Managing multiple mammalian pest populations
Wendy Ruscoe (Landcare Research) says that despite spending approximately $110 million per annum on the management of mammalian pests, they are still here and still threatening biodiversity conservation.
Even where pests are managed, effective control may be seriously constrained by the unpredictable responses of other pest species. For example, rodent numbers sometimes increase following possum control operations, which may lead to increases in stoat populations and a consequent decrease (through predation) of some bird populations.
In 2010, Wendy and her colleagues have completed a large-scale, multi-faceted experiment that has been investigating the driving factors in interactions between pest species and how these may affect the outcomes of pest control. Wendy says every man and his dog (literally) have worked on the project, with the key Landcare Research staff being Peter Sweetapple, Ivor Yockney, Roger Carran, Mike Perry and Sam Cave. There were eight 900-ha study sites in mixed podocarp-tawa forests across the Kaimai Ranges, Manukau Plateau, Whirinaki and Te Urewera (the last 2 requiring helicopter access).
The researchers were investigating whether:
food availability drives temporal variation in pest abundance
- removal of top-level predators results in increases of secondary pests because they are not being eaten
- removal of a pest population leads to increased competitor pest populations.
During the four years' of field work, the team experimentally manipulated pest populations, with each of the ‘treatments’ replicated over the eight study sites, by:
- controlling possums and rats with a one-off aerial 1080 baiting operation,
- using same control protocol for possums and rats but with continuous additional control of rats with toxic bait in bait-stations
- controlling stoats with continuously set traps, and
- no-treatment (no control).
On each site, the baseline population size and temporal changes of rats, mice, stoats and possums were monitored. Rats, mice and possums were live-trapped, marked with ear tags, and released during 5-night trapping sessions in November, February, May and August. Stoat populations were monitored using tracking tunnels and hair-collecting tubes, with the hair being used to identify individual stoats by DNA ‘fingerprinting’.
Additional small-scale experiments quantified how stoats (predators) and possums and rodents (primarily herbivores) modified their food intake rate with varying food availability. Ground-dwelling invertebrates were monitored using pit-fall traps before and after each control operation. Wētā were also counted in purpose-built wētā houses attached to trees.
Carrying out all this fieldwork was a huge logistical exercise and depended on skilled field staff. Mostly everyone camped or used huts for up to two weeks at a time, three sessions a year just for the monitoring. Wendy notes that they also needed a raft of permits … from Landcare Research (animal ethics approval), DOC (research permits and permits to land helicopters in some areas), consent from four iwi groups, permission to use veterinary drugs, cyanide licenses, Medical Officer of Health Approval. “Getting all these approvals was no easy task.” Wendy says they also worked with AHB to have the initial 1080 operation done (part of a job they were doing anyway), and local contractors did the continuous stoat trapping and rat control.
Results
Results of the experimental manipulations produced both expected and unexpected results.
- Removal of the top predator (stoat) from the system did not lead to an increase in the ‘meso-predator’ (rat) as hypothesized.
- However removal of possums using 1080 lead to a significant increase in the ‘competitor rats’ with rat numbers increasing to higher levels than they were prior to 1080 baiting and to higher levels than in the sites that weren’t poisoned at all.
- Similarly, on sites where both possums and rats were controlled to low levels, mouse population numbers increased to higher than they had been previously.
- Where rat populations were reduced, there was an observable increase in occupancy rates of the wētā houses by tree wētā - a favourite rat food.
The data collected from all these experiments is now being used to develop computer models of the four pest species (possums, stoats, rats and mice) and their complex interactions with each other and their environment. These models will be a significant breakthrough in predicting variation in pest abundance over time, and how secondary pests will respond to primary pest control. The models will enable pest managers to assess the relative biodiversity and economic benefits of alternative pest control strategies to protect conservation assets.
Wendy emphasises that “clearly, the benefits of pest control operations must be assessed at the ecosystem level if biodiversity assets are to be protected.”
Acclimatising in Antarctica (Tanya O'Neill)
Tanya O'Neill says "Superbly uneventful is how I would describe this year’s flight South. Smooth to the point where I found myself thinking ‘surely something is about to go wrong?’ I am not a pessimistic person by any means but after four attempts last season, firstly due to high turbulence over Canterbury, followed by bad weather at Scott Base, and finally mechanical issues with our ski-equipped Hercules mid-flight, I have reason to be a little sceptical about things going to plan first time round. But as the engines revved up for the final time on the Christchurch tarmac, I couldn’t help but smile … and not just because the ‘petrol-head’ gene I inherited from my Dad (a mechanic and Ford V8 man) gets a buzz every time an aircraft’s engines fire up and you are pushed back into your seat with force … but I smile because I am off again to one of the most mind-blowingly stunning, yet harshest continents on Earth. At that instant, as our packed to capacity US Antarctic Program Globe master C-17 lifted off the runway, I was a swirl of emotions: excited, feeling extremely fortunate, and raring to go.
"Not to mention tired. So what is involved in getting to Antarctica with the New Zealand Antarctic Programme? Firstly you have to secure logistic funding through the New Zealand Government and get your science approved. This is of course limited. Once that is in place the ‘Event Planning’ team at Antarctica New Zealand (crown research institute) get the ball rolling and everyone venturing South must have an up-to-date First Aid certificate, as well as Medical and Dental Clearance. I don’t envy the local GP performing my medical exam, some four pages long, I ventured out about 3 hours later having been poked and prodded, as well as a trip to med-lab for every imaginable test in the book! The day before departure all party members arrive in Christchurch to be kitted out in some very swish field clothing. So stylish we Kiwis are told to guard it with our lives when we visit our neighbours in the nearby US base of McMurdo Station as the primaloft orange and black jackets with cool Antarctica NZ penguin and fern logo have gone walk-about in the past!
"Touching down at Pegasus airfield on the Ross Ice Shelf is an awesome experience. The first thing one notices getting out of the plane isn’t the obvious cold, as you have been wearing your ECW gear (extreme cold weather - able to keep you toasty warm at – 40 oC) since you left Christchurch, rather it is the glare. Polarised sunglasses are a must. Next you notice the absence of greenery, trees, and for that matter anything that will give you a handle on scale, and therefore distance. The landscapes are vast, infinite, and somewhat indescribable – photos do not do them justice. Kiwi’s are greeted by staff from Scott Base, and quickly shuttled from the ice airfield to that familiar set of green buildings New Zealander’s have called home since the late 1950s.
"You quickly settle into life on Base. It’s a bit like school camp; things like mealtimes need to be structured to work. Everybody pitches in with the dishes. Breakfast is between 6 am and 8 am, lunch 12 noon, and so on. Bread is baked daily, something like 10 loaves of bread each morning (nobody is a fan of the crusts, so I am in my element!). Scott Base is a tropical 18 oC all year round. This is achieved by heating the outside air, which consequently drops the humidity indoors to an extremely dry <10%. Vaseline Intensive Care is scattered all over Base; and the blokes are quick to use it too! Another consequence is excess static, there are metal strips beside the Base phones, computers etc, and you have to discharge yourself (i.e. voluntarily give yourself a massive shock!) before touching electrical equipment. There are home comforts like a zippy café-style coffee machine (another vice of mine), and a cupboard full of home-baking. Scott Base has a bar with pool table, a well-equipped gym with treadmills, exercycles, and a bit of weights gear; and has the most beautiful lounge area in the world, with views out to the flagpole, the Ross Ice Shelf and aptly named White and Black Islands beyond.
"It’s not all luxury resort-style living, Base is but a hub full of scientists and artists on fellowship programmes, eager to get out into the field to start the programmes they’ve been planning for months and months. Antarctica is not named the most inhospitable continent for no reason, the weather forecast must be factored into every move, even a trip up nearby Observation Hill (a high point on Ross Island which Scott’s Party climbed and waited for their leader to return from the Pole) requires a trip to the sign-out book, an estimated time of return (they will come searching!), and extra clothing as even the most perfect day and quickly change.
"The first couple of days focused on reconnaissance, a lot of walking between Base and neighbouring McMurdo Station, up and around Observation Hill, and up Crater Hill, the site of the brand new wind turbines, which will play an important role in decreasing fossil fuel reliance at both stations. Born and raised in the Manawatu, wind turbines on the skyline remind me of home!
"The real science is set to start as I begin sampling disturbed and adjacent undisturbed sites to get handle on how soil properties change with human disturbance. "
Waikato University student Tanya O’Neill was studying for a PhD, looking at the impact human activity is having on Antarctic soils. In a series of stories, she shares some of the highlights and lowlights of life on the ice. Tanya was awarded the Murray Jessen Scholarship from Landcare Research.
Animal monitoring trip in Whanganui National Park
Roger Carran (Landcare Research) with a story of a 16-day field trip that got a lot more challenging than expected.
The aim of this trip was to establish lines of chew cards and tracking tunnels in several areas within the park to gauge animal abundance prior to an upcoming ‘low sow’ 1080 drop covering about 32,000 hectares of Whanganui National Park.
The trip was planned and organised by Landcare Research (in collaboration with DOC Whanganui) as part of the on reducing the amount of toxin being applied to the landscape whilst maintaining the effective kill rate of possums and rats.
The field team for this trip consisted of a real mix of Landcare Research staff, contracting staff, a couple of guys from Vector Control on the West Coast, and DOC staff based in Pipiriki. All in all we had an awesome crew of strong, competent and experienced bushmen.
Our first study sites were located in the middle of the park up the Whanganui River, so we based ourselves at John Coull Hut, approximately a one-hour up-river via jet boat from the DOC base at Pipiriki. Just before we arrived, there had been torrential rain (which lasted for the first couple of days of the trip) so the river was well up —we had an exciting trip upstream. Whole trees and bloated dead animals floated past. We got up to the hut without hiccup and tied the boat up to the trees sticking out of the water.
The work plan was for each person to be dropped off by jet boat at various points along the river in the morning. Then they were to navigate their way to a specific start point and establish three ‘chew card’ transect lines each before returning to a point on the river where the boat could pick them up. Accessing the park from the river is always a challenge. In many (if not most) places, the river cuts its way through steep sided gorges of soft and slippery Papa clay, making climbing out of the river almost impossible. So, finding appropriate access points was important, and of course these changed with the changing water levels as well.
Everything was running smoothly on the first morning. Everyone managed to negotiate the access points from the jet boat and the rain was easing up. In fact, we all had the work done in record time. It looked like it was going to be a trouble free day ... 'till we found out that one of our contractors had managed to cut his left index finger 90% of the way off with a Svord machete, very nice, very sharp.
From an H&S scenario, things worked in text book fashion. Everyone was carrying radios specifically programmed to the DOC frequencies, spare batteries, EPLOBs (emergency locator beacons), personal tracking devices, GPS’s, maps, compass, and in this case more importantly — first aid equipment. Uncannily, the contractor had just completed a first aid refresher course three days beforehand, and he managed to tape his fingers together and call for help. The DOC jet boat driver came and got him within a matter of minutes, having already called Emergency Services and DOC base to get a helicopter on its way. He was flown out to Hamilton Hospital and had surgery that afternoon to reattach the finger. Everyone did all the right things and the doctors reckon he’ll get 100% use of his hand and finger back, which really is amazing!
So there, we were one team member down. DOC and Landcare Research had in the meantime already organised for another contractor from the West Coast to join us for the remainder of the trip and was there the next day, this time without a machete. The weather fined up and the chew cards lines went out without any more incidents.
The forest and landscape surrounding the Whanganui River is steep and thick. However, the ridges are open and very easy to travel due to the high numbers of goats. Any form of understory has been long since munched by goats; you often come across small groups as you walk through the bush. Introduced over 200 years ago and reproducing at a rate of two sets of twins a year, they’ve stripped the vegetation with gusto.
After putting out all the chew card lines along the river, we split the team into two groups and moved to separate locations. One group headed back into the park near Ruatiti accessing the lines via quad bike, and the other group moved around to Whakahoro. Here we had a lot of interaction with different interest groups using the park; hunters, kayakers, horse trekkers and farmers. It’s always interesting to gauge people’s opinions on conservation and surrounding issues. Once we’d established all the lines, we headed back to Pipiriki to repeat the whole process all over again, bringing in and replacing all the ‘chews cards’ that had been out for a week to see what animals had been chewing them and get a score for the relative animal abundance in the study area.
Return trip to Whanganui National Park
Grant Morriss (Landcare Research) picks up the story.
Aerial 1080 baiting was completed in November 2009 and the monitoring crew were back in to check the results the next month. Roger Carran was unable to come on the trip but Grant Morriss led a crew of 5 experienced contractors assisted by local DOC staff. Unlike the first trip there were no severed appendages and things went remarkably smoothly. Many dead possums were observed while servicing the chew card lines, and the native birds heard and seen alive after the poisoning included robin, tomtit, whitehead, tūī, falcon, grey warbler, bellbird, and fantail. Bats were observed on twilight at the John Coull hut and a kiwi was also heard.
Chew cards were put out on the same lines used for the pre-poisoning and left for 7 nights before being collected and read. It was soon apparent there had been good reductions in rodent and possum interference on the chew cards. A 97% reduction in possum activity was recorded in areas where only 250g/ha of 1080 bait had been cluster-sown, which was better than the reductions measured in the standard sown blocks where 2kg/ha 1080 bait had been used. Reductions in rat activity were high as well with 98-100% reductions in the cluster and broadcast-sown blocks.
These results have contributed to formulating ongoing research into reducing sowing rates with aerial 1080 baiting with very good possum and rat reductions achieved in 2010 with cluster-sown rates as low as 167g/ha. Further operations are planned in 2011 with many thousands of hectares treated with lower sowing rates than is currently the standard.
Footnote: The contractor who almost cut his finger off on the first trip had a few months off work but now has full use of that finger. He has been back doing field work by Landcare Research since the incident.
Antarctic soils
Jackie Aislabie is a microbiologist and an Antarctic expert; she leads a research programme on on soils and micro-organisms that live in that very challenging environment.
The total ice-free area of Antarctica comprises less than 0.4% of the continent. The ice-free regions, of which about 90% are soil forming, are located mainly on the continental coastline, particularly on the Antarctic Peninsula and in the McMurdo Dry Valleys in the Ross Sea Region. Approximately half of the ice-free ground occurs in the Ross Sea Region, including the largest continuous expanse of ice-free ground, the McMurdo Dry Valleys. The soils are cold desert soils and depth to ice-cemented permafrost is > 70 cm. However, in coastal areas depth to ice-cemented permafrost is often < 70 cm and soils.
Antarctic soils are characterised by extremely low soil temperatures, with an average mean annual temperature ranging between –15°C and –40°C, and low soil moisture. Antarctic soils are diverse, mainly due to differences in land-surface age (which ranges from a few thousand to millions of years), parent material, topographic position, and local climate variation.
The prevailing soil conditions create a harsh environment for plant and animal life. Only a few plants and animals have managed to colonise and survive in ice-free regions. Microbes, however, are distributed throughout soils of the Ross Sea region, with highest numbers detected in moist coastal areas compared with dryer inland soils.
Ice-free areas are the most biologically active terrestrial sites on the Antarctic Continent. They are also the focus of human activity and continue to attract scientists and increasing numbers of tourists. The majority of the operating scientific research stations are located in ice-free regions. Click here to see a great photo gallery of soil scientists at work in some truly amazing landscapes!
Adélie Penguin Research
Scientists have been studying Adélie penguins (Pygoscelie adeliae) for over 50 years. Antarctica is one of the last places in the world where animals can be studied in a habitat still largely unmodified by man. It is thought that data on changes to penguin populations may reflect the impacts that humans and natural factors, like climate change, may be having on the marine ecosystem.
Landcare Research, in collaboration with a US research team, has been studying Adélie penguins in the Ross Sea region of Antarctica.
The Ross Sea is one of the most biologically productive regions of the Southern Ocean.
More than 38% of all Adélies (5 million penguins in 38 colonies) are found here, even though this region has less than 10% of the total Antarctic coastline.
Click here to find out more about what the scientists (and penguins) are up to.
Environmental protection of the Ross Sea region of Antarctica
Jackie Aislabie (Landcare Research) has spent many years working in Antarctica, and the image gallery that she and her colleagues have compiled provide a fascinating insight into many field seasons working on a variety of research.
Jackie and her team have been increasing fundamental knowledge and understanding of Antarctic soils - including soil climate and distribution, microbial diversity, and vulnerability to human activities. She currently leads a programme entitled “Environmental Domains Classification for the Ross Sea region”.
Ice-free areas of Antarctica (most of which are soil forming) are the most biologically active and vulnerable terrestrial sites in the continent. Much of the ice-free area in Antarctica occurs in Ross Sea region. New Zealand as an Antarctic Treaty partner is committed to the comprehensive protection of Ross Sea region and its dependent and associated ecosystems. Achieving this goal requires an understanding of the biogeographic character of terrestrial ecosystems in the Ross Sea region. To meet this need we are aiming to develop an environmental domains classification for Ross Sea region.
Environmental domains analysis (EDA) is a systematic environmental classification framework that allows similar environments (including small distinctive environments that are otherwise easily overlooked at the continental scale) to be grouped based on their environmental character regardless of their geographic location.
An environmental classification of Ross Sea region (within the context of our Antarctic-wide classification) will utilize a suite of environmental variables including climate, landform, soil, and biology data. We will gather and collate available data, along with that derived from our new research on soil attributes, climate and microbial diversity and abundance. As data is freely available for research purposes Antarctica provides an ideal opportunity to develop the next generation environmental domains analysis.
Antarctic - an extreme environment for soils
The total ice-free area of Antarctica comprises less than 0.4% of the continent, with the largest continuous expanse of ice-free ground in the McMurdo Dry Valleys. About 90% of the ice-free regions have formed soils, characterised by extremely low soil temperatures (average annual mean ranging between -15oC and -40oC) and low soil moisture. Antarctic soils are diverse mainly due to difference in land-surface age (a few thousand to millions of years), parent material, topographic position and local climate variation. Landcare Research has a rich history of Antarctic soils research dating back to the old Soil Bureau days, including soil distribution and climate, bacterial diversity, and vulnerability to human impacts (i.e. oil spills and trampling). Jackie Aislabie (Hamilton) leads the current soils research there.
In some areas, permafrost may be several million years old
Antarctic soils comprise a surface pavement and a seasonally-thawed active layer over permafrost, which is defined as soil that remains at temperatures <0oC for two consecutive years. The surface pavement is a layer of weathered gravel, stones or boulders (strong winds blow away the fine materials). Beneath the surface pavement is the active layer, often loose and unconsolidated material ranging in depth from 17 to 55 cm. The colour of the subsurface varies according to the age of the soil and parent materials.
Permafrost underlies all exposed ground surfaces, except for those heated by volcanic activity. Near the coast the permafrost is usually ice-cemented because of greater precipitation. At inland sites, particularly the dry valleys, the water content of the permafrost (generally <5%) is insufficient to cement the soil particles together, and described as ‘dry permafrost’. In some areas, permafrost may consist almost entirely of ground ice believed to be up to several million years old.
Low fertility
The soils typically have low levels of carbon and nitrogen (<2%) and are low in clay and consequently have little pH buffering capacity. A notable exception are soils under penguin rookeries, which have a carbon content of around 20% and total nitrogen around 10%.
Soil pH ranges from highly alkaline (pH 9) in soils of coastal regions (chlorides from wind-blown sea water predominate) to weakly acidic (pH 6) in inland soils at high elevation (nitrates and sulphates predominate). The salts in older, drier soils commonly occur as a firm layer about 5-15 cm below the soil surface, with salt encrustations common under surface pavement rocks.
Soil conditions are harsh for plant and animal life
The prevailing soil conditions create a harsh environment for plant and animal life. Only a few plants and animals have managed to colonise and survive in ice-free regions. Microbes however, are distributed throughout soils of the Ross Sea region with higher numbers detected in moist coastal areas compared with dryer inland soils. Ice-free areas are the most biologically-active terrestrial sites on the Antarctic continent.
Impact of human activity
Ice-free areas are also the focus of human activity and continue to attract scientists and increasing numbers of tourists. The majority of scientific research stations are operating in ice-free regions. There has been long-standing concern about the potential long-term impacts of people on these fragile soils.
For his PhD research, Malcolm McLeod (Landcare Research) has been mapping soils of the Wright valley and determining their vulnerability to human impacts. The team’s collaborators are Dr Megan Balks (University of Waikato), Professor Jim Bockheim (University of Wisconsin), Dr Cathy Seybold (United States Department of Agriculture).
A new approach to biodiversity protection: local scale to landscape scale
All over New Zealand, there is a huge groundswell of interest in pest control for biodiversity protection. Small, isolated patches may not provide enough habitat to allow native species to survive in perpetuity, but a coordinated approach across tenures could develop ‘metapopulations’ at a landscape scale. (A metapopulation is a group of spatially separated but interacting populations of the same species). Hence local community groups, DOC, regional councils, large and small businesses and research providers all have a role to play.
Recently Wendy Ruscoe, Al Glen (both Landcare Research at Lincoln) and their colleagues began work with the Robertson Foundation Aotearoa, Hawkes Bay Regional Council, and Department of Conservation to set up the Wide-Scale Predator Control Project. This aims to apply ‘metapopulation’ management over a scale of tens of thousands of hectares in the Maungaharuru-Tutira Area. The project considerably expands on DOC’s initiatives in the Boundary Stream Mainland Island (BSMI), which has had pest control for 15 years. Bellbird Bush and Opouahi Reserve nearby, as well as many smaller privately-owned blocks in Hawkes Bay also provide protected native habitat but are separated from BSMI by unprotected agricultural land.
Populations of native species including kiwi, kokako, North Island robin, and Hawkes Bay tree weta persist in BSMI but are constantly under threat of predation by invading pest animals. The threat of predation is especially intense when native animals attempt to move between these protected areas. Wendy and colleagues will determine whether the level of predator control implemented across the pastoral landscape is sufficient for a suite of native species (birds, reptiles and insects) to make more effective use of the network of native forest remnants. They also plan to determine if fragments close to BSMI show a more rapid response than isolated fragments. Models of connectivity between patches will help managers and community groups decide where and when to carry out landscape-scale pest control within limited budgets.
Three Kings Islands — 56 km but an eon from New Zealand
The Three Kings Islands is a small archipelago only 56 km off the northern tip of New Zealand. They are the sole emergent part of the Three Kings Ridge, the remnants of an island arc that formed during the break-up of East Gondwana. Some rocks have been dated to 19-22 million years ago but some people believe that the islands originated much earlier than that. It is uncertain how long the Three Kings Ridge has been isolated from the mainland but certainly for many millions of years! The very northern tip of New Zealand was probably an island as well at some stage in the ancient past, and is geologically more similar to the Three Kings than to the rest of New Zealand.
The Three Kings Islands host a large number of endemic species. For example, the beetle fauna is estimated to be 35% endemic and the terrestrial snail fauna is highly endemic. There are several endemic plant species including 12 trees and shrubs. What is intriguing is that the closest relatives of some of these Three Kings species are found not on mainland New Zealand but in New Caledonia, Australia, or elsewhere in the Pacific – extraordinary for a small group of islands within eyeshot of the coast of mainland New Zealand!
Thomas Buckley and Rich Leschen (Landcare Research, Auckland) have used comparative phylogenetic analysis to infer the age and biogeographic origins of insect fauna of the Three Kings Islands. They densely sampled six insect lineages (five beetle groups and one stick insect group) throughout New Zealand and sequenced mitochondrial DNA1 to assess phylogenetic relationships2 and determine the relative ages on the Three Kings Islands and mainland New Zealand lineages.
The analyses indicate that the Three Kings fauna have been long isolated from mainland New Zealand. Thomas and Rich recovered two biogeographic patterns:
- The first pattern was seen in three taxa, which had sister group relationships between the Three Kings and the adjacent Te Paki/North Cape area at the very northern tip of New Zealand.
- The second pattern, inferred in the other three taxa, had sister groups that were widespread throughout most or all of New Zealand.
These results are consistent with continual emergent land on the Three Kings Ridge since at least the Miocene and a lack of land connections between the Three Kings Islands and mainland New Zealand during Pleistocene sea-level lowering. Despite their narrow separation, westerly ocean currents may be limiting dispersal between the Three Kings Islands and mainland New Zealand.
The results further exemplify the biogeographic significance of the Three Kings biota. The high levels of genetic differentiation of insect populations on the Three Kings relative to the ‘sister’ populations from the mainland, coupled with a more ancient endemic element, exemplifies the importance of these islands for New Zealand biodiversity.
The research also highlights the importance of strengthening conservation measures to ensure the survival, integrity and recovery of the biota. The islands were occupied by early Māori. By the time Europeans arrived in mid seventeenth century, Manawatawhi was largely denuded of trees. But, following the eradication of goats in the1940’s, forest has begun to regenerate. Any active restoration and augmentation using species sourced from mainland New Zealand would requires detailed knowledge of both the biogeographic history of the islands and the phylogenetic distinctiveness of species populations to determine appropriate areas for sourcing related populations for translocation.
Buckley, T.R. and R.A.B. Leschen. 2012. Comparative phylogenetic analysis reveals old and recent lineages on the Three Kings Islands, New Zealand. Biological Journal of the Linnaean Society, in review
Footnote 1: Mitochondria are tiny organelles or structures inside a cell that help convert food energy into a form that cells can use. Although most DNA is packaged in chromosomes within the nucleus of a cell, the mitochondria also have a small amount of their own DNA.Because mitochondrial DNA is passed through the maternal line, it enables researchers to trace an organisms direct lineage back in time.
Footnote 2: A phylogeny depicts a pattern of descent. Traditional classification schemes were often based upon similar morphological characteristics that may or may not reflect descent, whereas phylogenies are based upon derived characters that are shared by all of the descendants from a common ancestor. Recent efforts to unravel the phylogenetic ‘tree of life’ utilize morphological, anatomical and molecular characters even entire genomes. Because of their predictive power, phylogenies are becoming more widely used in plant classification, biodiversity assessment and ecological studies of character evolution.
Field techs talking about field work
Generally all field technicians agree on the best and the worst aspects of field work:
Best bits — Getting to work in the outdoors in wilderness areas that few others ever get to, helicopter flights through spectacular scenery, travelling around the country to work at many different sites, catching up with the techs from other sites.
Worst bits — Working in wet bush in the pouring rain. Working in areas with an over abundance of plants such as kekie, supplejack, bushlawyer and hookgrass.
Three highly-experienced field techs from Landcare Research reflect on what they like about their jobs.
Roger Carran
One of the aspects I enjoy the most as a field technician is getting to work in remote locations, far away from large-scale human interference. Witnessing natural ecosystems and environmental processes and exploring this beautiful country. For example, spending 2 hours fighting my way through seemingly impenetrable central North Island supplejack in the rain, to be rewarded with the haunting song of a pair of kōkako calling to each other from the tops of tall rimu trees in the early morning mist. Or while working on the Aldermen Islands, having the 20 cm long x 2 cm wide centipede with blue legs and massive fangs share my sleeping bag with me, and the tuatara that came to see what all the fuss was about when I told the centipede to find its own sleeping bag. Little things like that make the effort seem well worth it.
Nature and wildlife aside, it’s often the pure simplicity of life in the hills that draws me back time and time again. Spinning a few yarns with the other techs over a one-pot-wonder dinner. And there’s always the hope that it won’t rain tomorrow!
Grant Morriss
I remember the good old days when field work was a care-free escape from the office. Nowadays, 'cause I'm an old crusty bugger, I have to run the job and make sure it keeps to budget. Still fieldwork is good opportunity to escape from lab techs hassling me about my vanishing hair and increasing girth, and recover some of the fitness that got sucked out of me sitting in front of the computer. Recently I've had some magical chopper flights through our Southern mountains to reach our field site at Lake McKerrow in Martins Bay. As with any work in Fiordland, you have to expect rain every trip but the hut we used was superb with a free standing wood burner that you could really get cranking to get the wet gear dried out. The minor discomforts of fieldwork are forgotten once you're in dry clothes.
Mike Perry
While not as glamorous as some study sites, the Orongorongo field station is a great place for conducting fieldwork. After a day (or sometimes night) of scrambling round the hills in the kiekie, supplejack and often in the rain you can come back to the station, jump in the shower, put your gear through the dryer and have a cup of tea on the couch. The field station has a long history of fieldwork that began in the 1940’s with the Department on Internal Affairs and later the old DSIR. The amount of work that has been carried out there over the years is staggering.
While only 18km from Wellington, it takes almost an hour of 4WD to get in. The track is pretty good but the high intensity rainfall that often occurs there has a habit of washing out the stream crossings overnight so a bit of spade work is often required. While often feeling quite remote, the valley gets a lot of use by the public—approximately 40 private huts and 25,000 people walking the Orongorongo track each year. So we are often bumping into members of the public and explaining our work to them. Most can’t fathom why we go to the effort of catching possums and rats, just to let them go again.
Fieldwork for new peat bog research imminent!
It is now less than a week until we will board a plane in London for the long flight to New Zealand to meet up with colleagues and undertake the fieldwork for our new project investigating New Zealand’s peat bogs and past climate change. To find out more about exactly what we’re doing in the project please read the previous story in our collection.
Between the project team, we’ve organised and carried out countless fieldwork trips, but I always still find this time period approaching departure is a strange mixture of excitement and trepidation – have I booked and organised everything I need to? Is there some vital bit of kit I should have got hold of which we will only realise is missing when we’re on the middle of a bog and it’s too late?! Let’s hope not! As a researcher involved in studying the past, fieldwork preparation often involves the gathering of lots of heavy and bulky coring equipment to retrieve the deep sediment records that we then study. Although a pain to deal with in transit, having a load of kit with you is at least slightly reassuring. But with this new project, we are just studying the plants growing on the surface of the peat bogs (in particular, the wire rush, or Empodisma to give it its Latin name) to understand more about how they react to changes in climate. This means the pile of kit I have gathered together in my office over the past few weeks (pictured!) is rather small and certainly very un-reassuring!
We have also been spending some time finalising the permissions we need to access all the sites we would like to work on. This is an often complicated task that has been admirably handled by Rewi Newnham at Victoria University, on the ground in NZ. At one site, there are five local stakeholders with a vested interest including two local iwi, conservation and farming interests. Thankfully everything seems to be sorting itself out and it’s great news that some of those interested parties will be joining us out in the field next week. I really believe that as academics funded by the public purse we have a duty to let as wide a range of people as possible know about our research, so this is a great start. To further this goal, we will post several blogs over the next few weeks on different aspects of how the fieldwork is going on the OurFuture site. If you’d like to know any more about the project or have any questions, then please get in touch.