Ken Ryan

Antarctic Biology & Ecophysiology School of Biological Sciences


Teaching in 2017

Research interests

ecophysiology, Antarctic algae, marine ecology, plant secondary metabolites, electron microscopy, light microscopy

AProf Ken Ryan profile picture


  • Climate change biology – Ecophysiological effects of UVB, temperature and salinity on photosynthesis, primary productivity and biodiversity in Antarctic coastal marine ecosystems
  • Symbiosis in temperate invertebrates
  • Flavonoids in higher plants – responses to UVB radiation
  • Biological electron microscopy and taxonomy, especially toxic dinoflagellates
  • Light microscopy including phase contrast, fluorescence, and confocal.
  • UV radiometry

Research interests

The focus of my recent research has been on the effect of climate change on the growth and productivity of Antarctic marine algae. These studies have involved the use of high-tech oxygen microelectrodes and PAM fluorometers, to measure in situ the primary productivity of sea ice algae that grow on the underside of Antarctic sea ice. This work has been extended to the bacterial component of sea ice with the work of my MSc (now PhD) student, Andrew Martin. Simon Davy (Ecophysiology) has joined my Antarctic team.

The Antarctic physiology techniques naturally extend to the symbiotic relationships between algae and invertebrates (anemones and corals) in collaboration with Dr Simon Davy (SBS).

The effect of UV radiation on land plants has been a focus, utilizing a specially designed “ultraviolator” plastic house for the treatment of plants with enhanced UVB solar radiation. The role of bio-active compounds such as bioflavonoids in the protection of plants from the deleterious effects of UVB has been examined. With the appointment of a post doctoral fellow in the SBS, I hope to revitalize and extend this work into new areas including the chemosystematics of higher plants, and to this technology to the study of evolution in Hebe.

In the late 1980’s a network of UVB radiometers was set up in centres of population in New Zealand. I became involved in this project in the early 1990s and extended it to allow real time broadcasting of actual UV burn-times over local radio stations. Data are recorded, calibrated, archived, and periodically published.

Several papers on electron microscope features of a number of species of algae have been published in collaboration with botanists at Te Papa and NIWA.

Please follow the link below to hear RadioNZ's "Our Changing World" interview on Sea Ice Cores from 30 July 2009


PhD students

  • Andrew Martin - Bacterial metabolic activity in Antarctic sea ice (PhD)
  • Eileen Koh - Biodiversity of prokaryotes in Antarctic sea ice (PhD)
  • Meghana Rajanahally - Ecophysiology of Antarctic sea ice algae (PhD)
  • Gesine Pufal - Hygrochastic seed capsules in NZ alpine plants (PhD) (joint supervision with Phil Garnock-Jones)
  • Lisa Bryant - Amphipod diversity and taxonomy in the Ross Sea (PhD)
  • Mark Heath - The physicochemical regulation of Phormidium spp. growth and anatoxin production(PhD)

Selected publications

Koh, EY, Phua W, Ryan KG (2011) Aerobic anoxygenic phototrophic bacteria in Antarctic sea ice. Environmental Microbiology Reports In press 2011

Ryan KG, McMinn, A, Hegseth, E., and Davy, S K (2012). The effects of Ultraviolet-B radiation on Antarctic sea ice algae. J. Phycology In press

Heath MW, Wood SA, Ryan KG (2011) Spatial and temporal variability in Phormidium abundance and anatoxin production in two New Zealand rivers. Aquatic Microbial Ecology. DOI: 10.3354/ame01516.

Ryan KG, Tay, M-L., Martin, A., Davy, S.K. (2011) Chlorophyll fluorescence imaging analysis of Antarctic bottom-ice algae: responses to light and salinity stress. Journal of Experimental Marine Biology and Ecology 399, 156-161.

Koh YE, Cowie ROM, Atamna-Ismaeel, N, Martin AR, Béjà O, O’Toole R, Davy SK, & Ryan KG (2010) Light harvesting bacteria in Antarctic sea ice. Applied and Environmental Microbiology. 76, 5918-5925.

Martin A, Hall JA, Ryan KG (2009) Low salinity and high UV-B radiation reduces single-cell activity in Antarctic sea ice bacteria. Applied and Environmental Microbiology. 75, 7570 – 7573.

Ryan K.G., Cowie R., Liggins L., McNaughtan D., Martin A, and Davy S (2009). The short-term effect of irradiance on the photosynthetic properties of Antarctic fast-ice microalgal communities. J Phycology. 45, 1290-1298.

Ryan KG, Burne, A, Seppelt R (2009). Historical ozone concentrations and flavonoid levels in herbarium specimens of the Antarctic moss Bryum argenteum. Global Change Biology. 15, 1694-1702.

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