Research Activities at CMRA
The following are research profiles of people currently undertaking research at the Cass Mountain Research Area:
Mark L. Galatowitsch
PhD: Freshwater Ecology
I have been studying how generalist aquatic invertebrates (damselflies, water boatmen, and caddisflies) are able to exploit a wide range of habitats (lakes and temporary tarns). While at Cass I was able to do a variety of experiments to find out how susceptible the aquatic nymphs are to fish and insect predators, whether they can tolerate drying conditions in temporary tarns, and the extent that the adult generalists can fly as adults between habitats. To further explore the extent of dispersal I have been using genetic analyses (microsatellites) to test the extent that damselflies move between habitat types, which may be critical to maintain their populations under such varied habitat conditions.
BSc (Hons): Freshwater Ecology
My specific species of interest is Galaxias paucispondylus - commonly known as the alpine galaxiid - which is a small non-migratory fish endemic to the south island of New Zealand. It has an extremely patchy and poorly understood distribution along the eastern side of the Southern Alps. My goal is to discover how global change drivers such as temperature warming, altered disturbance regimes and changing distributions of invasive species (such as trout) interact to determine the current distribution of alpine galaxiids, and whether these factors can be used to make models to predict how their distributions may be altered by climate change.
My research is focused on high resolution remote sensing and its implications to better simulate and understand micro-climate dynamics in complex terrain. It utilizes over thirty ground surface temperature sensors and various soil moisture sensors to validate satellite-derived surface properties, locally collected atmospheric data in combination with high-resolution irradiance models to better understand variations in surface energy fluxes in complex terrain, and will draw on data acquired as part of the STABX experiment to model micro-climatic processes at very high resolutions with applications e.g. to frost prediction, understanding topographic shadows and temperature gradients, and various boundary layer related questions.
MSc: Freshwater Ecology
I have spent the last two summers at Cass helping on a variety of different projects, and starting a few things of my own. This summer I will be looking at current mosquito distributions in the area and how climate change might affect native and introduced mosquito populations, by investigating how drying can affect predator-prey interactions between mosquitoes and predators such as damselflies, dragonflies and beetles. I feel so lucky to be able to work at Cass; it is a big part of the reason I chose to do post-grad research at UC, and I love being part of a community of like-minded people every summer.
I spent last summer up at the Cass Mountain Research Area working as part of a team undertaking a complete vegetation survey of the 1775 ha. I got to see the diverse plants and communities present in the area after battling through prickly plants such as matagouri and gorse. Our team found numerous species that had not been previously recorded in the wider area and confirmed the presence of nationally declining species such as Olearia lineata in the CMRA. This coming summer I will continue my research there working on O. lineata, O. bullata and their native herbivorous moths. I want to understand why O. lineata is declining compared to the more common O. bullata and look at the relationship between the moths and the Olearia plants which will have implications for the future conservation of these species.
PhD: Freshwater Ecology
The major component of my PhD in freshwater ecology is based at the Cass Research Field Station. I am investigating the potential impact of climatic warming on the reproduction biology of a group of endemic insects called mayflies (Ephemeroptera). Mayflies are the most primitive group of winged insects still living today and are particularly sensitive to changes in their environment. Some of the New Zealand mayfly taxa are important to science because they are the most ancient mayflies on the planet. In an ecological setting, mayflies are an important food source for predatory aquatic insects, freshwater fish and insectivorous forest and riverine birds. The Cass Field Station makes ecological research within the Southern Alps possible by providing access to the unspoilt alpine rivers and mountain landscapes. Use of the field station means expensive research costs like travel and accommodation can be kept to a minimum. It also provides vital laboratory facilities and opportunities for field-based experiments, without the risk of public interference.
I studied the factors preventing hybridisation in Celmisia, New Zealand's mountain daisies, for my Master's in Ecology. I investigated the role of phenology, pollinators, and the survival of natural hybrids as potential reproductive isolating barriers in Celmisia. I lived at Cass, but worked in the nearby Craigieburn Ranges. Prior to undertaking my master's degree I spent several summers living at Cass helping out on a wide range of other projects, and wilding tree control. I thoroughly enjoyed living in the mountains and working alongside enthusiastic people involved in new and exciting research.
PhD: Freshwater Ecology
My PhD research aims to determine the key biotic and abiotic factors that lead to food web stability. In particular I am interested in how habitat size/stream size influences community structure and the importance of organism body size in determining this structure. I am also investigating the importance of body size and other species traits in determining the strength of predator-prey interactions in food webs. Cass is an ideal location to carry out field work for my research. There are a wide range of streams in the Waimakariri Catchment which, span a large disturbance regime (stable spring-fed to flooding disturbed braided rivers), range in stream size, and range of top fish predators. I have also been able to build a series of experimental mesocosms at the field station which have allowed me to carry out my experiments over the last three years.
For my PhD I am studying the connections between terrestrial and freshwater ecosystems through the exchange of subsidies and how those subsidies affect interactions within the recipient ecosystem. Cass is a great place to use as a base for surveys as there are a variety of ecosystems types within a short distance. I also have a long-term mesocosm experiment set up at the Cass field station in cattle troughs looking at the interactive effects of different terrestrial subsidies (leaves, terrestrial invertebrates) to freshwater food webs. Being able to set-up experiments in the natural systems that you are studying and being based nearby so that you don’t have to drive for hours to get to your study is a priceless aspect of Cass.
PhD Student - University of Bristol
My main interest is to understand how alien species integrate and affect the structure of animal-plant interaction networks in both ecological and evolutionary perspectives. By integrating experimental, survey and theoretical approaches, throughout my PhD I aim to test whether (i) alien-promoted mutualistic changes lead to a cascade effect on native foodwebs?, and (ii) how plant-pollinator communities respond to the invasion of alien species in different geographic areas? To answer the first question, I study the effects of the highly invasive Himalayan balsam plant (Impatiens glandulifera) on the seed set, seed herbivores, and parasitoids of native communities in semi-natural and disturbed areas in Bristol, UK, supervised by Prof. Jane Memmott. For the second question, I study the invaded sub-alpine communities of plant and pollinators at Cass Field Station area, in the South Island of New Zealand, in collaboration with Prof. Jason Tylianakis from the University of Canterbury. In both areas, I have been collecting data to look at the mutualistic process at the level of plant-flower visitor networks, pollen-transport, and stigma-pollen interactions.
Dr. Hamish Greig
Academic: Freshwater Ecology
I have spent the past 12 years testing hypotheses in community ecology with experiments and observations across the diversity of freshwater habitats in the Cass basin. My BSc Hons studied interactions between trout, caddisflies and beech leaves to show predators can have strong cascading effects in the detritus-based food webs of forested streams. My PhD focused on the influence of drying on community assembly and species interactions in the invertebrate assemblages of wetlands and small lakes. More recently I have been working as a Postdoc with Angus McIntosh on Marsden-funded research that is unraveling the effects of ecosystem size on stream communities. We have been using a series of laboratory and stream experiments within the Cass Field Station research area to address the causes and consequences of changes in top predator size with habitat size. Cass is a truly remarkable base for field-based ecology, and although I have recently begun an assistant professorship at U Maine, USA, I hope to maintain strong research ties to the field station.
Josh van Vianen
Research Assistant: Ecology
I have been working as part of a team collecting data from the plant communities growing in the Cass field station warming plots. Our aims are to assess how plant community assemblages will respond under predicted global change scenarios. Specifically we are investigating how plasticity in a range of plant traits will influence the way plant communities are assembled with increased global temperatures and increased atmospheric nitrogen deposition. Global change biology is a growing field of science and the warming plots at Cass provide an ideal environment to carry out research in this area.
Dr. Laura Young
I have worked at Cass on and off for nine years on numerous research projects, including my own PhD research on seed dispersal of subalpine plants by kea and exotic birds and mammals. Most recently I’ve been part of a team concerning the management of the CMRA. We produced a management plan in consultation with most of the CMRA users and recommended the types of management actions that should be done in the area over the next ten years. These incorporated issues such as plant and animal pest control, grazing, and setting up systems that enable CMRA users to keep track of what research is currently taking place and where, producing maps and other resources that aid in a better understanding of the research area and the new web pages for the CMRA. Last summer we began to establish long-term monitoring systems such as permanent plots and photo points to measure vegetation change, mammal monitoring and climate stations. We sampled 120 vegetation plots on a grid network across the CMRA and recorded ca. 400 vascular plant species! We recruited many keen volunteers and cut and marked a walking track from the field station through Sugarloaf Bush and down to the Waimakariri River on the other side. We now have better access to the other side of the CMRA and hope to encourage more research and teaching activities across a wider range of habitats. I am one of many proud and dedicated researchers who use the CMRA and have always felt exceptionally privileged to have this place as a resource. Cass is like a second home to many of us during our field research and we hope it stays this way for many years to come.
Prof. David Norton
Chair of the CMRA Management Committee
Having done my PhD research based at Cass and Craigieburn some 30 years ago I have always had a particular fondness for the place. In recent years there has been a considerable increase in the number of people using Cass and the CMRA. We felt that it was timely to formally start addressing some of the management issues that have arisen over the years, e.g. wilding conifers, which have until now been dealt with on an ad hoc basis. We produced a management plan in 2012/13 and I am now involved in implementing this management plan as well as research on a variety of aspects of plant ecology at the CMRA.
Dr. Stinus Lindgreen
Marie Curie research fellow: Computational biology
Global climate change is arguably the largest problem facing mankind today. We know that bacterial communities are important for e.g. carbon sequestration and nitrogen fixation, but precious little is known about how bacterial ecosystems react to climate change. My research project is aimed at elucidating this important aspect of climate change research through next-generation sequencing and bioinformatics. I have collected soil samples from a multi-year field experiment established at Cass that investigates the effects of increasing temperature and the use of nitrogen containing fertiliser. Through the application of so-called metagenomics and metatranscriptomics on these samples, we will look at both the DNA - i.e. which bacteria are present and in what abundance - and the RNA - i.e. what genes are they using and to what degree. This will make it possible to answer key questions about the effect of these important climate change drivers on microbial communities. My research is funded by a Marie Curie Fellowship through the European Union.
Field Technician: School of Biological Sciences
I have helped students and staff with their research at Cass for over twenty years. Some of the things I’ve helped out with include: doing weed transects, limnological work on the lakes in the Cass basin, building a pipeline to supply water from Reservoir Bush to the research lab, assisting with transects of vegetation and planting germination experiments. I’ve also been involved with assisting in fire regeneration experiments, doing surveys of local wildlife and electrofishing for bugs and fish in local rivers. I also help out with making tracks and battling with the wilding conifers in my spare time. I enjoy fieldwork at Cass very much because I get to work in a unique mountain landscape on interesting projects with keen staff and students.