Anna Berthelsen

Anna Berthelsen

Marine Ecologist

Role at Cawthron

Anna is a marine ecologist with over ten years of research and consultancy experience. Her specialties include the ecology of coastal soft sediment, estuarine vegetation and rocky reef habitats. She also has expertise in water quality.

She has recently been involved with estuary-related research, including the Oranga Taiao Oranga Tangata (OTOT) programme funded by the Ministry of Business, Innovation and Employment (MBIE). Within this, she led research relating to estuarine indicators of ecological health and the compilation of a national estuary dataset to facilitate this work. Anna is particularly interested in freshwater and marine connections, and has researched relationships between stream and estuary health. She also contributed to the MFE-funded ‘Managing Upstream : Estuaries State and Values Project’, which aimed to provide freshwater management guidance for estuaries.

Anna is also interested in climate change impacts, as well as mitigation and adaption opportunities provided by marine ecosystems. Her work in this area to date relates to estuarine and rocky reef communities.

Anna is engaged in aquaculture research, including her role in managing a component of Cawthron’s MBIE-funded Salmon Feed Conversion Efficiency research project. This involves investigating relationships between water quality and salmon feeding at aquaculture farms (marine and freshwater) throughout the South Island.

Additionally, Anna conducts work for local government and a variety of commercial clients, including monitoring and environmental impact assessments for aquaculture, ports and outfalls as well as estuary and reef monitoring. 

Technical skills, experience and interests

  • marine ecology (soft sediment, rocky reef, water column)
  • ecosystem functioning
  • environmental health assessment
  • habitat mapping
  • marine environmental effects monitoring (e.g. aquaculture, outfalls)
  • benthic surveys (baseline and assessment of effects)
  • climate change relating to marine ecosystem


  • PhD Marine Science. University of Auckland NZ, 2014
  • BSc Hons (first class) Zoology and Ecology. University of Otago and University of Canterbury NZ, 2005


Anna Berthelsen