Comparison of independently derived benthic invertebrate and demersal fish ecoregionalisations for the Kerguelen Plateau

International audience; Ecoregionalisation is a process that aims to identifyareas with distinct biological content and associatedenvironmental conditions. It improves on manytraditional approaches to regionalisation by explicitlyincorporating biological data into classifications.Ecoregionalisations are useful for improving our ecologicalunderstanding of marine ecosystems and forinforming spatial management. This includes providinginformation to aid in defining and prioritising areas forconservation, evaluating current spatial managementarrangements, targeting monitoring efforts and managinghuman activities (e.g. Grant et al., 2006; Douglass etal., 2014). The Kerguelen Plateau is a highly productiveregion of the southern Indian Ocean that supports lucrativedemersal fisheries (Duhamel and Welsford, 2011).It is subject to spatial management in the form of marineprotected areas (MPAs) with varying levels of protection(Commonwealth of Australia, 2014; Koubbi et al.,2016). Recently two ecoregionalisations have been independentlygenerated for the northern Kerguelen Plateau;one for benthic invertebrates (Martin et al., 2018) andanother for demersal fish (Hill et al., 2017). Here weconduct a preliminary analysis examining the congruencebetween these ecoregionalisations that representdifferent components of the demersal ecosystem.