Josh Stewart

Joshua Stewart


Joshua Stewart is pursuing a PhD in Marine Biology from Scripps Institution of Oceanography. He is interested in improving the conservation outlook for threatened marine species - especially highly mobile marine vertebrates - by addressing the complexities of spatial ecology and connectivity in marine systems while engaging stakeholders to implement management strategies at local and regional scales. Between his undergraduate and graduate studies, Joshua spent a year as a Rolex Scholar, working with conservation professionals in diverse fields from conservation photography and communication to endangered species research. These experiences showed him the value of the many different approaches to conservation and how they can work synergistically to achieve conservation successes. During the scholarship year, Joshua also began working with manta rays, a species threatened globally by targeted fisheries, bycatch and accidental entanglement in discarded fishing gear. He went on to become a founding member of The Manta Trust, a non-profit that has improved the conservation status of manta and mobula rays around the globe by informing and supporting international, national and local management. Joshua's dissertation research is focused on the spatial ecology and population connectivity of oceanic manta rays. He is helping to improve management strategies for populations of oceanic mantas by taking into account the species' movements, home ranges and habitat use identified by his research. Joshua uses a combination of methods including satellite telemetry, stable isotope analysis, and genetics to build a complete picture of spatial ecology and population structure across a range of spatial and temporal scales. He is also interested in using quantitative techniques to improve the management of threatened species, and his current work is focused on developing models that can incorporate multiple data types to better estimate the trends of oceanic manta populations that are impacted by fisheries. In addition, Joshua has always been passionate about communication, and he uses print media, public lectures, photography, and video as tools to communicate important conservation concepts to a broad audience.

Fellow at a Glance

Fellowship Year:
Academic Background:
UC San Diego, Scripps Institution of Oceanography, PhD
Current Position:
PhD Candidate
UC San Diego, Scripps Institution of Oceanography
Coastal & Marine Issues
Currently Working On:
Spatial ecology and population connectivity of oceanic manta rays
6051 La Jolla Hermosa Ave
La Jolla, California 92037
(917) 566-3226

A vibrant community of environmental leaders