Issie is working on a novel approach to stream restoration, targeting the lack of biological recovery observed after physical stream restoration measures. She hopes to show that lack of community recovery is a result of ‘negative resistance and resilience’, whereby degraded stream communities become extremely stable, leaving them trapped in their degraded state even after physical stream conditions improve. Through a series of mesocosm experiments and a trait-based meta-analysis of existing community data, Issie aims to develop and test a ‘push-pull’ method for stream community restoration, first destabilising the degraded community (‘push’) then helping to establish a healthy one (‘pull’).
Research Interests: resistance, resilience, restoration, community ecology, biological traits, mesocosms.
For more information check out Issie’s Blog
Aisling is using conservation genomics tools to help rehabilitate our freshwater ecosystems for our future generations. For her PhD, she is privileged to work in partnership with an exceptional team including mana whenua, conservation practitioners and primary industry to improve resilience in the declining mahinga kai species kēkēwai/kōura/freshwater crayfish. Together, they are using a combination of genomic and non-genomic information to inform management of kēkēwai (e.g., translocations) to enhance conservation, customary and commercial outcomes. Aisling also loves getting outdoors and working with fellow students and the Ōtautahi community as part of UC’s Student Volunteer Army.
Research interests: conservation genomics, kēkēwai, kōura, freshwater crayfish, ecology.
There are a number of research projects that have focused on the physical restoration of waterways and habitats, however, there is little known about reintroducing native species back into rehabilitated environments. Reseeding of native species that could potentially assist with stream rehabilitation is the most logical “next step” in stream restoration. Channell’s research focuses on using kākahi, freshwater mussels (Echyridella sp.) to act as a biological tool to assist with waterway restoration efforts. Kākahi are ideal candidates as they perform a number of ecologically important functions in waterways. These functions include acting as bio-engineers which can physically shape environmental habitats; bio-indicators, which can assist with assessment of water quality; and filter feeders, which may help with removal of particulates and contaminants.
Research interests: kākahi (freshwater mussels), multi-trophic translocations of threatened endemic mahinga kai species into rehabilitated waterways.
Alpine tarns are data deficient ecosystems in New Zealand. Alex’s research aims to create baseline physical and chemical data for these systems. She also aims to compile macroinvertebrate community data. During her research Alex has surveyed a number a tarn clusters at various elevations and locations in the Canterbury and Westland regions, and taken macroinvertebrate and plant samples for taxonomy and stable C and N isotope analysis. Using the C and N signatures she hopes to be able to construct food-webs for these tarns and even help to inform future management action.
Research interests: alpine tarns, stable isotopes, food-webs, macroinvertebrates, communities.
Understanding how biotic filters (i.e. species competition) can shape macroinvertebrate communities in freshwater systems could be important for improving biological restoration. My thesis will focus on the interactions between Potamopyrgus antipodarum, a freshwater snail that can dominate restored Canterbury low land streams, and colonizing mayflies, caddisflies and stoneflies. I will use both in-stream mesocosms and artificial stream systems to identify the mechanisms by which P. antipodarum, at high densities, interacts with other macroinvertebrates. I also hope to identify how increasing P. antipodarum densities affects the interaction strength, and at which density the interaction strength is significant enough that they start to exclude other macroinvertebrates from colonizing and establishing. Subsequently, this density could be used as a guideline for restoration projects, by reducing snail numbers to a certain level, it may facilitate the re-colonization of other macroinvertebrate species.
Research interests: biological restoration, negative resistance and resilience, species interactions and community assembly.
Most streetlights around New Zealand are being converted from high-pressure sodium lamps (HPS) to more energy efficient light emitting diodes (LEDs) by mid 2021. Little is known about the effect of artificial light at night on freshwater environments. Jessica’s research aims to determine the influence of LED lighting on freshwater insect communities. She is particularly interested in how a range of colour temperature LEDs with differing spectral profiles affect freshwater adult insects in the Christchurch and greater Canterbury area. She is also looking into how distance of LED lights from streams affects the attraction of freshwater adult insects to LEDs. Jessica’s research, as part of a larger NIWA project, hopes to improve knowledge of the ecological effects of LED lights at night.
Research interests: freshwater adult insect ecology, artificial light at night, human altered environments.
BSc (hons) Students
Amy van Lindt
Stream restoration projects are often successful in improving stream physical conditions, however, the associated recovery of biodiversity is failing. Tolerant biotic communities, consisting of species such as the small mud snail Potamopyrgus antipodarum, dominate degraded stream ecosystems and persist after physical stream restoration has occurred. Recent work suggest that these restoration resistant communities are preventing colonisation of more-desired fauna (mayflies, stoneflies, caddisflies). Amy's research will involve a series of mesocosm experiments investigating a novel way to displace mud snails through predation by freshwater crayfish Paranephrops zealandicus, and tests whether this interaction can then enhance the success of desired colonisers.
Research interests: stream restoration, negative resistance and resilience, kēkēwai (freshwater crayfish), biological interactions.