Safeguarding the future of reef manta rays

Dr Joanna Harris followed her passion for this majestic species to lead research on conserving their fragile populations
Marine scientist Joanna Harris swimming with a reef manta ray in the Indian Ocean
Joanna Harris, BSc (Hon) Applied Marine Zoology, MRes Applied Marine Science

My work has helped to advance our understanding of reef manta ray migrations, habitat use and feeding ecology, which is essential for developing effective protection strategies.

Dr Joanna Harris, BSc (Hons) Applied Marine Zoology, MRes Applied Marine Science, PhD Marine Sciences
After learning to snorkel when I was very little, I fell completely in love with the ocean and marine life conservation, so when it came to choosing a university, the University of Plymouth seemed like the ideal option, as it is world-renowned for its marine science facilities and researchers.

My passion for reef manta rays was cultivated through my degree thanks to an assignment I had to do on the species. While researching, I came across the Manta Trust, a UK and US registered charity, and learnt about everything they do to protect threatened ray species.

The hard work and dedication of the Manta Trust’s scientists and staff were inspiring. I knew then that I wanted to dedicate my research to helping protect mantas, so I contacted them with an idea for a research project.
With the support of the University of Plymouth and the Manta Trust, I conducted the research for my honours project. I then continued as a researcher for the charity for my MRes and PhD and became the Project Lead for the Manta Trust’s Chagos Manta Ray Project.

More about the Chagos Manta Ray Project

The Chagos Manta Ray Project is an affiliate project of the Manta Trust, a UK-registered charity formed in 2011 with a vision of a sustainable future for the ocean, where manta rays and their relatives thrive in healthy, diverse marine ecosystems. The Manta Trust collaborates with affiliates around the world through research, education, and expert advice to drive the policies and practices necessary to conserve manta rays and their relatives. The Chagos Manta Ray Project was established by the Manta Trust in 2013, and Joanna took over as project lead in 2019.
Joanna Harris swimming with reef manta rays
Coral reef with small tropical fish
Two reef manta rays swimming near a coral reef

Conducting crucial research with worldwide impact

My research involves studying the dynamic relationship between reef manta rays (Mobula alfredi), zooplankton and physical oceanography.
This research is crucial in allowing us to understand how reef manta rays use the Chagos Archipelago’s ecosystems and which environmental cues dictate their movements. Much like the Plymouth Sound and Tamar Estuaries marine protected area (MPA), the remote reefs of Chagos’ MPA are a refuge for many species, including rays. Studying this setting in depth will give us precious insights into the importance of such areas for mantas in the Indian Ocean.
I believe this study will also highlight the impacts of human activity and climate change on reef manta rays. If we can accurately identify these threats, we can work to ensure the conservation of ray populations worldwide.

I’m proud to say that my work has helped to advance our understanding of reef manta ray migrations, habitat use and feeding ecology, which have been used to develop effective protection strategies.

One such strategy is the designation of Egmont Atoll as an Important Shark and Ray Area by the IUCN Species Survival Commission Shark Specialist Group – an intervention that will allow us to protect and further study this unique habitat.
Reef manta ray swimming over coral
Brain coral
Joanna Harris wearing a mortarboard while on a boat in the Chagos Archipelago, Indian Ocean

Advice for future marine scientists

A key bit of advice I would give anyone who wants to work in a similar field is firstly to develop your knowledge on the subject at every opportunity and, while studying, make use of software and other tools that are industry standards, such as R and ArcGIS.
Next, it is important to make yourself known to organisations you are keen to work with, so embark on volunteering or internships.
Finally, once you have the necessary academic and practical skills, use your initiative to find gaps in research that you could fill and propose a project to an organisation.

Seize every opportunity to hone your skills and advance your knowledge in the field you want to enter. Being proactive to fill gaps in your own knowledge – and in research in general – is the key to succeeding as a scientist.

Rising stars

Celebrating some of our amazing recent graduates
Mornington Peninsula aerial ocean and beach