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Being able to predict the distribution of a species and possible dispersal corridors and barriers, are likely to increase our knowledge of the availability of suitable habitats for that species, as well as knowledge on how populations are connected. Knowing the distributional patterns of a species also increases our understanding of a species’ ecological and biogeographical processes which can be used for management applications, especially when it comes to invasive species, commercially important species and in this case study, highly mobile predators. In this study, authors tested environmental niche modeling as a tool to predict potential global distributions of the broadnose sevengill shark, *Notorynchus cepedianus* (Péron, 1807). Three model variants were implemented: the global fit (global population of the species) and the regional fit (subpopulations in the Southwest Atlantic and southern Australia), as merged and individual variants. A presence-only ecological niche modeling approach was applied in this case, due to the fragmentary availability of global presences and absences for this shark species. Presence- only distributional data was collected from various literature sources, social media, as well as from the OBIS and GBIF repositories. The resulting global fit predictions revealed broad suitable habitat areas for N. cepedianus, across temperate regions of the Northern and Southern Hemispheres (figure). The regional fit results for subpopulation niche patches were less similar than expected, with sharks occupying colder environmental conditions in the Southwest Atlantic than they do in southern Australia. Authors identified three major ocean basins as dispersal corridors that facilitate population connectivity and discussed possible explanations for why there are unoccupied suitable areas not currently accessed by the species. Overall, the study highlights the potential of using global and regional data for assessing the global habitat suitability for a species and provides considerations for applying environmental niche models to other highly mobile species.
De Wysiecki, A. M., Cortés, F., Jaureguizar, A. J., & Barnett, A. (2022). Potential global distribution of a temperate marine coastal predator: The role of barriers and dispersal corridors on subpopulation connectivity. Limnology and Oceanography, 1-15.