Megafauna show pervasive yet distinct affinity to ocean fronts: the urgent need for adaptive conservation in a warming world

Brito-Morales, I.; Dewitte, B.; Sudre, F.; Rohner, C. A.; Hazen, E. L.; Scales, K. L.; Le Corre, M.; Jaeger, A.; Laran, S.; Bousquet, O.; Sequeira, A. M. M.; Davies, T. E.; Dunn, D. C.; Nel, R.; Hannah, L.; Rossi, V.

doi:10.1101/2025.06.17.660201

bioRxiv · 10.1101/2025.06.17.660201

Megafauna show pervasive yet distinct affinity to ocean fronts: the urgent need for adaptive conservation in a warming world

Brito-Morales, I.·Dewitte, B.·Sudre, F.·Rohner, C. A.·Hazen, E. L.·Scales, K. L.·Le Corre, M.·Jaeger, A.·Laran, S.·Bousquet, O.·Sequeira, A. M. M.·Davies, T. E.·Dunn, D. C.·Nel, R.·Hannah, L.·Rossi, V.

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Abstract

Fronts are ephemeral structures in the ocean that mark the boundaries between water masses of different properties, attracting a wide range of marine organisms, from plankton to whales. Despite their fundamental role in marine ecosystem functioning, the association with biodiversity has mainly focused on single species in regions with high data availability. Here, using multidecadal datasets on dynamical and thermal fronts, satellite tracking, and aerial observations, we assess marine megafauna associations with ocean fronts in the ecologically rich yet highly turbulent Mozambique Channel. We find that a diverse array of species associate with various ocean fronts, although the strength and type of affinity vary across taxa. Downscaled climate change simulations predict significant spatial shifts in front-rich areas by the end of the century. As climate change reshapes ocean front dynamics, adaptive management strategies will be essential to balance conservation and resource use in these critical ecosystems. TeaserOcean fronts attract marine megafauna, but climate change might alter these habitats, requiring adaptive conservation strategies.

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Brito-Morales, I., Dewitte, B., Sudre, F., Rohner, C. A., Hazen, E. L., Scales, K. L., Le Corre, M., Jaeger, A., Laran, S., Bousquet, O., Sequeira, A. M. M., Davies, T. E., Dunn, D. C., Nel, R., Hannah, L., Rossi, V.. 2025-06-23. Megafauna show pervasive yet distinct affinity to ocean fronts: the urgent need for adaptive conservation in a warming world. https://doi.org/10.1101/2025.06.17.660201

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