Islay Diane Marsden is a New Zealand academic marine biologist and toxicologist, and is a professor emerita at the University of Canterbury.
She is interested in physiological ecology of marine invertebrates, and focuses especially on molluscs and Crustacea.
She has worked on understanding adaptations that allow survival in intertidal habitats, looking at traits such as oxygen uptake, and energy use.
[1] She has also worked on how environmental factors such as microplastics, heavy metals, and toxins from certain dinoflagellates have on the reproduction and survival of marine and estuarine species.
[3] She is on the international advisory board of the Journal of Biological Education, and was a general council member of the New Zealand Marine Sciences Society until 2020.