On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

Some examples of specific stable isotope research that NIWA is currently involved in include the following research projects:

  • Antarctic ecology: Antarctic toothfish trophic ecology and migration; Distribution, morphology and ecology of Macrourus whitsoni and M. caml (Gadiformes, Macrouridae) in the Ross Sea region; Diet and trophic niche of Antarctic silverfish (Pleuragramma antarcticum) in the Ross Sea, Antarctica.
  • Cetacean studies: Dietary studies reveal that male humpback whales do not just each krill; Population, habitat and prey characteristics of blue whales foraging in the South Taranaki Bight; The influence of fasting and opportunistic feeding on the stable isotope values of baleen whale skin; New insights into the feeding ecology of Hector’s dolphins. (Cephalorhynchus hectori) inferred from stable isotope mixing models; Demography and ecology of southern right whales wintering at Campbell Island, New Zealand.
  • Megafaunal ecology: Highly migratory species diet and movement studies.
  • Freshwater ecology: Tracing sewage-derived organic matter into a shallow groundwater food-web using stable isotope and fluorescence signatures.
  • Marine and freshwater nutrient dynamics: Response of surface nutrient inventories and nitrogen fixation to a tropical cyclone in the South-West Pacific; Regenerated primary production dominates in an upwelling shelf ecosystem, northeast New Zealand;  Sedimentary nitrogen uptake and assimilation in the temperate zooxanthellate sea anemone Anthopleura aureoradiata.Marine and freshwater ecosystem structure.
  • Deep sea ecology: High intraspecific variability in the diet of a deep-sea nematode: Stable isotope and fatty acid analyses of Deontostoma tridentum on Chatham Rise, Southwest Pacific.
  • Marine hazards: the effects of the Kaikoura earthquake on ecosystem structure in the Kaikoura Canyon.
  • Fish studies: Variation in morphology and life history strategy of an exploited sparid fish; Matching and mismatching stable isotope (δ13C and δ15N) ratios in fin and muscle tissue among fish species – a critical review; Effect of ingestion on the stable isotope signature of marine herbivorous fish diets.
  • Seabird ecology. e.g. Sex-specific foraging during parental care in a size monomorphic seabird, the Australasian gannet (Morus serrator); Does low seasonality drive reduced duration of migration in temperate brown skuas?; Feeding Ecology of Black Backed Gulls – changes over time; Breeding Mottled Petrel feeding ecology and distributions on Cod Fish Island; Fluttering shearwater diet and movements in Hauraki Gulf; Diving petrel dietary studies; Wintering in the sun: niche partitioning by three non-breeding Pterodroma petrel species in the equatorial Pacific Ocean; Stable isotope signatures delineate the non-breeding distributions of sooty shearwaters Puffinus griseus in the North Pacific Ocean; Higher trophic level prey does not represent a higher quality diet in a threatened seabird: implications for relating population dynamics to diet shifts inferred from stable isotopes; Foraging ecology and choice of feeding habitat in the New Zealand Fairy Tern, Sternula nereis davisae; Contemporary and historical separation of transequatorial migration between two genetically-distinct seabird populations; Foraging ecology of the Cook’s petrel Pterodroma cookii during the austral breeding season: a comparison of its two populations; A stable isotopic investigation into the causes of decline in a sub-Antarctic predator, the rockhopper penguin Eudyptes chryoscome.
  • Marine microbial community structure and function
  • New Zealand’s ocean carbon cycle model: understanding marine carbon cycling and food-webs to predict climate change effects.
  • Terrestrial Ecology: Foliar and soil nitrogen and δ15N as restoration metrics at Pūtaringamotu Riccarton Bush, Christchurch city; Aborigine-managed forest, savanna and grassland: biome switching in montane eastern Australia.
  • Gas Emissions: Mitigation via chemical di-nitrogen formation: Exploring ways to remove nitrogen while bypassing nitrous oxide emission aims to develop cost effective techniques for removing reactive N and reducing N2O emissions in grazed agricultural systems.
  • Climate studies: Reconstructing past variations in precipitation and temperature in New Zealand on decadal to millennial timescales through the analysis of skeletal remains of heads of midge larvae; Climate reconstruction using the New Zealand freshwater bivalve Echyridella menziesii from Lake Rotorua.
  • Deep Sea Geochemistry: Isotopic studies of methane seeps – tracing sources of carbon.
  • Terrestrial ecology: Feeding ecology of ants.
  • Tracking sediment sources: Using fatty acid compound specific isotope analysis.