Communities and Interactions under the Sea
The Marine Ecosystems research group is uniquely placed on the South Island, New Zealand, with access to a broad range of habitats from tropical to polar as well as facilities including ocean-going vessels and research laboratories. As a consequence much of the work that we do takes advantage of environmental gradients to resolve basic structural features of ecosystems and underlying processes.
We carry out empirical research with a focus on metapopulation dynamics, food web structure and biogeochemical cycling in coastal marine systems.
We use direct observations, field sampling, laboratory experiments and environmental chemistry to study marine processes in a broad range of Southern Ocean environments including Coastal Otago, Fiordland, Stewart Island, the Sub-Antarctic Islands and Antarctica, as well as in the South Pacific.
Our research has a strong emphasis on providing science to support management to ensure the future sustainability of our marine ecosystems.
- Dr Chris Hepburn
- Professor Miles Lamare
- Associate Professor Keith Probert
- Dr Candida Savage
- Dr Lucy Wing
- Professor Stephen Wing
Bacterioplankton carbon cycling along the Subtropical Frontal Zone
Biology and ecology of inlet and estuarine macrobenthos.
Benthic structure and function of the Otago shelf and upper slope.
Biodiversity and ecosystem functioning
Food web structure in Antarctica and sub-Antarctic Islands
Conservation of marine resources in Fiordland
Nutrient cycling in estuarine and coastal environments
Effects of environmental conditions across latitudinal gradients
Fisheries ecosystems in coastal kelp forests
Spatial management of marine resources, marine reserves, rotating harvest
Role of omnivores in kelp forest community structure
Regionally focused research:
Over the last 15 years of research in Fiordland, our work has focused on:
Food web structure and biogeochemical cycling in the New Zealand fjords with emphasis on how terrestrial carbon is made available to marine consumers, the consequences of species loss for food web dynamics and how changes to food web structure influences higher trophic level groups such as rock lobsters, reef fish, marine mammals and sea birds.
Ongoing research in Fiordland includes quantifying carbon burial in fjord sediments, reconstructing historical changes in phytoplankton production and community structure, and understanding degradation pathways of organic matter across environmental gradients.
These studies are supported by environmental chemistry techniques including stable isotope analysis and compound specific analysis of fatty acids, algal pigments and terrestrial biomarkers.
We also carry out studies on population structure and metapopulation dynamics in these environments employing both stable isotopes and trace elemental analysis of otoliths and skeletal material of crustaceans, and in collaboration with geneticists.
These studies have been used to support management decision making in Fiordland leading to the Fiordland Marine Management Act 2005.
We have an active programme monitoring biological and physical changes across the region in the new network of marine reserves and marine protected areas to support the adaptive management process.
The University of Otago Department of Marine Science runs a field laboratory at Deep Cove, Doubtful Sound, enabling to us to work there for extended periods.
Availability of iron to form light-absorbing pigments in phytoplankton limits productivity in the Southern Ocean.
Seabirds such as albatross and penguins receive iron from food webs across vast areas of the Southern Ocean and congregate around the sub-Antarctic islands in huge numbers to breed.
We are using the latest technical advances in tracing sources of carbon and iron in food webs using stable isotopes to resolve nutrient flux and bioaccumulation in these systems and answer this important question:
Does bioaccumulation of iron by seabirds enhance productivity in the vicinity of the sub-Antarctic islands?
We are using the University of Otago’s research vessel, The RV Polaris II, to survey sub-Antarctic waters around the Auckland Islands and the Snares Islands.
We are working in association with Dr Will Rayment, who studies southern right whales at the Auckland Islands
Our research programme in Antarctica has been supported by Antarctica New Zealand and been conducted out of Scott Base.
This project focuses on understanding the role of seasonal sea ice in the nutritional dynamics of the benthic community. In particular we are interested in how the sea ice microbial community is used as a food source for larvae and benthic fauna.
Additionally we are working to understand the role of nutrients that are recycled from higher trophic levels (penguins and seals) in driving productivity within the benthic community under the ice.
We employ oceanographic surveys and ice diving in the field and stable isotope and trace metal chemistry in the lab to study these communities and processes, along a gradient of sea ice seasonal persistence and extent.
The waters around Stewart Island at Pegasus Inlet, Paterson Inlet and Port Adventure are regions with relatively pristine native forest catchments offering rare control sites in investigations of the effect of catchment on nutrient dynamics and estuarine processes.
Paterson’s Inlet Marine Reserve and Te Whaka ā Te Wera/ Paterson Inlet Mātaitai Reserve are ideal locations for studying kelp forest community structure and dynamics including population structure of pāua, kina (sea urchins) and giant kelp (Macrocystis pyrifera). We have focused on the influence of giant kelp on the distribution of fishes and invertebrates and on material dynamics along productivity gradients.
We have also been involved in monitoring of Patersons Inlet Marine Reserve for the Department of Conservation.
We like to teach the field component of MARI 432 (Subtidal Marine Ecology) at Stewart Island.
The University of Otago Department of Marine Science runs a field laboratory at Oban, enabling to us to work there for extended periods.
Otago Coast – Paua Fisheries Ecosystems
Dr Chris Hepburn is the PI of this project. He co-supervises students with Steve Wing, who acts as an academic mentor.
This project works to provide ecological information to complement local knowledge to enable community-based management of coastal fisheries and work within the research group Te Tiaki Mahinga Kai.
Estuaries and Coasts around New Zealand
We investigate the ecological and biogeochemical consequences of nutrient enrichment in estuaries and coasts from intensification of land and marine farming. New Zealand offers an excellent opportunity to study estuarine ecosystems with varying nutrient loads, from pristine systems to estuaries with elevated nutrient concentrations. We quantify spatial and temporal variation in rates of nutrient cycling, growth rates of key organisms, and food web dynamics in estuaries.
We also study trophic linkages and connectivity between estuaries and coastal benthic communities. The findings of this research highlight the importance of integrative ecosystem-based management.
In addition, we are conducting manipulation experiments to understand relationships between biodiversity and the role of key functional groups in influencing ecosystem functions.
South Pacific – Coral Reef Ecosystems
We conduct research in the South Pacific on effects of multiple stressors including elevated nutrients and temperature stress on physiological responses of corals in an era of climate change. A key aspect of this research is quantifying nutrient cycling in the coral holobiont and understanding plant-animal interactions between the symbionts and host cells.
Subtropical Frontal Zone off Otago
Marine bacterioplankton are the master recyclers of the oceans, playing a central role in driving global biogeochemical cycles of elements essential to life. Therefore, any process affecting marine bacterioplankton activity might have a huge impact on carbon fluxes and global climate. Mesoscale hydrological features like fronts (i.e., a boundary between two distinct water masses) are widespread in the ocean and have commonly been associated with increased productivity. However, the degree of impact of these mesoscale features on marine bacterioplankton and the molecular mechanism explaining how bacterioplankton respond to fronts are unknown.
Federico Baltar’s group investigates the impact of the Subtropical Frontal Zone, conveniently located close to Otago, on bacterioplankton carbon cycling
- Baltar, F., Stuck, E., Morales, S., & Currie, K. (2015). Bacterioplankton carbon cycling along the Subtropical Frontal Zone off New Zealand. Progress in Oceanography, 135, 168-175. doi: 10.1016/j.pocean.2015.05.019
- Savage C, SF Thrush, AM Lohrer and JE Hewitt (2012) Ecosystem services transcend boundaries: Estuaries provide trophic subsidies and influence functional diversity in coastal ecosystems. PLoS ONE 7(8): e42708, doi:10.1371/journal.pone.0042708
- Lill AWT, GP Closs, M Schallenberg and C Savage (2012) Impact of berm breaching on hyperbenthic macroinvertebrate communities in intermittently closed estuaries. Estuaries and Coasts 35: 155-168
- Leduc, D. and Probert, P.K. (2011). Small-scale effect of intertidal seagrass (Zostera muelleri) on meiofaunal abundance, biomass, and community structure. Journal of the Marine Biological Association of the U.K. 91:579-591.
- Dufour, C., Probert, P.K., Savage, C. (2012). Macrofaunal succession of stranded Durvillaea antarctica on a southern New Zealand exposed sandy beach. New Zealand Journal of Marine and Freshwater Research DOI:10.1080/00288330.2012.676557
- Schüller SE and C Savage (2011) Spatial distribution of diatom and pigment sedimentary records in surface sediments in Doubtful Sound, Fiordland, New Zealand. New Zealand Journal of Marine and Freshwater Research 45: 591-608
- Bierschenk AM, C Savage, CR Townsend and CD Matthaei (2012) Intensity of land use in the catchment influences river ecosystem functioning along a freshwater-to-marine continuum. Ecosystems 15(4): 637-651
- Morley AS, Martin SM, Bates AE, Clark MS, Ericson J, Lamare M, Peck LS (2012) Spatial and temporal variation in the heat tolerance limits of two abundant Southern Ocean invertebrates. Mar Ecol Progress Series 450: 81-92
- Lurman GJ, Blaser T, Lamare MD, Peck LS, Morley S (2010) Adaptation in ancient animals: Mitochondrial plasticity in brachiopod (Liothyrella sp.) smooth adductor muscle as a result of season and latitude. Marine Biology 157: 907-913
- Wing SR and L Jack (2012) Resource specialization among suspension feeding invertebrates on rock walls in Fiordland is driven by water column structure and feeding mode. Marine Ecology Progress Series 452:109-118
- Jack L and SR Wing (2011) Individual variability in trophic position and diet of a marine omnivore is linked to kelp bed habitat. Marine Ecology Progress Series 443:129-139
- Jack, L. and S.R. Wing (2010) Habitat quality drives size structure and fecundity of the red rock lobster (Jasus edwardsii) among marine protected areas in Fiordland. Marine Ecology Progress Series 404: 161-172.
- Jack, L., S.R. Wing and R.J. McLeod (2009) Prey base shifts in the red rock lobster Jasus edwardsii in response to habitat conversion in Fiordland marine reserves: implications for effective spatial management. Marine Ecology Progress Series 381: 213-222.
- Wing SR, McLeod RJ, Leichter JJ, Frew RD, Lamare MD (2012) Sea ice microbial production supports Ross Sea benthic communities; influences of a small but stable subsidy. Ecology 93: 314-323
- Hepburn C.D, Hurd C.L, and Frew R.D. (2012) Tracing uptake and transport on nitrogen derived from sessile fauna by the giant kelp Macrocystis pyrifera using a 15N enriched isotope tracer. Aquatic Biology. DOI 10.3354/ab00382.
- Cornwall, C., Hepburn, C.D., Pritchard, D., Currie, K., McGraw, C., Hunter, K.,Hurd, C.L. (2011). Macroalgae switch to a low-energy inorganic carbon source under conditions simulating ocean acidification. Journal of Phycology. 10.1111/j.1529-8817.2011.01085.x