Profile
This is research is key in allowing us to gain a better understanding of how reef manta rays uses the archipelago ‘s ecosystems and which environmental cues dictates their movements. Additionally, it will also give us a precious insight into the role of the Marine Protected Area (MPA) surrounding the Chagos Archipelago as a refuge for this species within the Indian Ocean. In order to gather such information, I will be using satellite and acoustic telemetry, in-situ plankton sampling coupled with oceanographic monitoring.
I believe this study will also highlight the impact human activities and climate change have on reef manta rays. Thus enabling a more accurate identification of the threats to the conservation of reef manta ray populations worldwide.
With the unsustainable depletion of manta and devil rays in the Indian Ocean, the Chagos Archipelago no-take MPA is a refuge that supports their survival, so ensuring their ongoing protection in the region is essential
Biography
My Projects
Other interests
The reef manta ray (Mobula alfredi) are precious creatures subject to increasing pressure both from human activities and climate change. Direct exploitation for their gills has recently increased following a rise in demand from traditional Chinese medicine caused an added pressure on manta ray populations. Nonetheless, the often overlooked touristic pressure on these animals is increasingly threatening this species and its habitat. While working in the Maldives my research focused on identifying key areas of habitat use where such pressure is increasing. I was able to identify drastic habitat and temporal changes in the way reef mantas use these areas and, thus, enabled more effective conservation management practices.
My Publications

The Illegal Exploitation of Threatened Manta and Devil Rays in the Chagos Archipelago, One of the World’s Largest No-Take MPAs
Harris, J.L., Stevens, G.M.W. (2024). The illegal exploitation of threatened manta and devil rays in the Chagos Archipelago, one of the world’s largest no-take MPAs. Marine Policy.

First Records of the Sicklefin (Mobula tarapacana), Bentfin (Mobula thurstoni), and Spinetail (Mobula mobular) Devil Rays in the Chagos Archipelago
Harris, J.L., Collins, C., Spalding, M., Stevens, G.M.W. (2024). First records of the sicklefin (Mobula tarapacana), bentfin (Mobula thurstoni), and spinetail (Mobula mobular) devil rays in the Chagos Archipelago. Fish Biology.

Spatial and Temporal Variations in Reef Manta Ray (Mobula alfredi) Meso-Scale Habitat Use and the Implications for Conservation
Harris, J.L., Hosegood, P., Embling, C.B., Williamson, B.J., Stevens, G.M. (2024). Spatial and temporal variations in reef manta ray (Mobula alfredi) meso-scale habitat use and the implications for conservation. Aquatic Conservation.

Intraspecific Differences in Short- and Long-Term Foraging Strategies of Reef Manta Ray (Mobula alfredi) in the Chagos Archipelago
Harris, J.L., Embling, C.B., Alexander, G., Curnick, D., Roche, R., Froman, N., Stuhr, M., Fileman, E.S., Hilbourne, S., Carter, R., Murray, A., Savage, J., Stevens, G.M.W. (2023). Intraspecific differences in short- and long-term foraging strategies of reef manta ray (Mobula alfredi) in the Chagos Archipelago. Global Ecology and Conservation.

A Review of a Decade of Lessons From One of the World’s Largest MPAs: Conservation Gains and Key Challenges
Hays, G.C., Koldewey, H.J., Andrzejaczek, S., Attrill, M.J., Barley, S., Bayley, D.T.I., Benkwitt, C.E., Block, B., Schallert, R.J., Carlisle, A., Carr, P., Chapple, T.K., Collins, C., Diaz, C., Dunn, N., Dunbar, R.B., Eager, D.S., Engel, J., Embling, C.B., Esteban, N., Ferretti, F., Foster, N.L., Freeman, R., Gollock, M., Graham, N.A.J., Harris, J.L., Head, C.E.I, Hosegood, P., Howell, K.L., Hussey, N.E., Jacoby, D.M.P., Jones, R., Pilly, J.S., Lange, I.D., Letessier, T.B., Levy, E., Lindhart, M., McDevitt-Irwin, J.M., Meekan, M., Meeuwig, J.J., Micheli, F., Mogg, A., Mortimer, J.A., Mucciarone, D.A., Nicoll, M.A., Nuno, A., Perry, C., Preston, S.G., Rattray, A.J., Robinson, E., Roche, R., Schiele, M., Sheehan, E.V., Sheppard, A., Sheppard, C., Smith, A.L., Soule, B., Spalding, M., Stevens, G.M.W., Steyaert, M., Stiffel, S., Taylor, B.M., Tickler, D., Trevail, A.M., Trueba, P., Turner, J., Votier, S., Wilson, B., Williams, G., Williamson, B., Williamson, M.J., Wood, H. and Curnick, D.J. (2020) A review of a decade of lessons from one of the world’s largest MPAs: conservation gains and key challenges. Marine Biology.