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Dr Caitlin O'Hara Blain

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Research Fellow


I completed a BSc with specialization in microbial and molecular biology at the University of Vancouver Island in Canada. In the final years of my undergraduate degree I took up SCUBA diving and discovered my passion for marine science. I then moved to St. John’s, Newfoundland to complete my MSc in marine science at Memorial University of Newfoundland. My thesis focused on the ecology of a highly acidic brown alga, Desmarestia viridis

My PhD thesis focused on the effects of increasing turbidity on the subtidal kelp Ecklonia radiata. Increasing turbidity poses a major, yet often overlooked, threat to coastal marine ecosystems. My research combined field studies across a large-scale turbidity gradient in the Hauraki Gulf, north-eastern New Zealand, and mesocosm experiments to determine the effects of turbidity, and the associated decrease in benthic light, on the physiological performance, productivity and persistence of Ecklonia.

Research | Current

Hilltop to Oceans: Coastal marine ecosystems as carbon sinks and buffers for ocean acidification

Healthy coastal marine ecosystems support a multitude of metabolic processes and regulatory functions that are critical for maintaining complex food webs and ecosystem functions. However, marine ecosystems, and the ecosystem services they provide, are under increasing threat from anthropogenic-induced stressors. For example, loss of vegetated habitats such as seagrasses and kelp forests due to sedimentation and poor water-shed management not only reduce critical habitat for numerous species but greatly reduce primary production and ultimately degrade the capacity of such ecosystems to act as short- and long-term carbon reservoirs. The extent to which these functions have been compromised by anthropogenic stress and how this might change with climate change is unknown.

This project is using an interdisciplinary approach, combining remote sensing, physiology and ecosystems ecology to estimate how the conservation and restoration of healthy marine ecosystems can potentially mitigate the effects of anthropogenic carbon dioxide emissions and climate change. 

Areas of expertise

  • Rocky reef ecology
  • Kelp forest ecology
  • Ecosystem resilience
  • Anthropogenic stressors
  • Phycology
  • Scientific diving

Selected publications and creative works (Research Outputs)

  • Blain, C. O., & Shears, N. T. (2020). Nutrient enrichment offsets the effects of low light on growth of the kelp Ecklonia radiata. Limnology and Oceanography10.1002/lno.11449
    Other University of Auckland co-authors: Nick Shears
  • Blain, C. O., Rees, T. A., Hansen, S. C., & Shears, N. T. (2019). Morphology and photosynthetic response of the kelp Ecklonia radiata across a turbidity gradient. LIMNOLOGY AND OCEANOGRAPHY, 65 (3), 529-544. 10.1002/lno.11321
    Other University of Auckland co-authors: Nick Shears
  • Blain, C. O., & Shears, N. T. (2019). Seasonal and spatial variation in photosynthetic response of the kelp Ecklonia radiata across a turbidity gradient. Photosynthesis research, 140 (1), 21-38. 10.1007/s11120-019-00636-7
    Other University of Auckland co-authors: Nick Shears
  • Blain, C. O. (2018). Effects of turbidity on the kelp Ecklonia radiata The University of Auckland. ResearchSpace@Auckland.
  • Blain, C., & Gagnon, P. (2014). Canopy-Forming Seaweeds in Urchin-Dominated Systems in Eastern Canada: Structuring Forces or Simple Prey for Keystone Grazers?. PLoS ONE, 9 (5), e98204-e98204. 10.1371/journal.pone.0098204
  • Gagnon, P., Blain, C., & Vad, J. (2013). Living within constraints: irreversible chemical build-up and seasonal temperature-mediated die-off in a highly acidic (H2SO4) annual seaweed (Desmarestia viridis). Marine Biology, 160 (2), 439-451. 10.1007/s00227-012-2101-8
  • Blain, C., & Gagnon, P. (2013). Interactions between thermal and wave environments mediate intracellular acidity (H2SO4), growth, and mortality in the annual brown seaweed Desmarestia viridis. Journal of Experimental Marine Biology and Ecology, 440, 176-184. 10.1016/j.jembe.2012.12.013

Contact details

Primary office location

Level G, Room G01
New Zealand