Future distribution patterns of cuttlefishes under climate change

Abstract While most coastal communities are expected to have been negatively impacted by climate change, cephalopods have thrived with shifting ocean conditions. However, whilst benefitting from the same physiological flexibility that characterized cephalopods, cuttlefish remain bounded to specific locations by their particularly low vagility. To test the beneficial effects of climate change on cuttlefish, Species Distribution Models were applied on nine species of genus Sepia to assess distribution on present and different representative concentration pathway (RCP) scenarios (2.6, 4.5, 6.0, and 8.5; CMIP5) for the years 2050 and 2100. We show that projections of future cuttlefish distribution decrease relative to present model predictions. Harshest hit species, Sepia braggi, was observed to decline as much as 30.77% (from present 55.26% to 24.48% at RCP 8.5 in 2100), to Sepia officinalis with low maximum decrease of 1.64% (from present 59.62% to 57.98% at RCP 8.5 in 2100). Increases in habitat suitability occurred mostly at higher latitudes, while habitat decrease was predicted for the tropical regions and lower latitudinal limits of species distribution. Cuttlefish will not benefit from future changes in climate, as their habitats will decrease in suitability. If suitability of habitat translates into cuttlefish abundance, many coastal fishing communities in the global south will be affected by the future decreases in these fishing resources. Additionally, as potential “sea canaries” for coastal ecosystems, we may see many species and habitats from these systems affected by climate change, namely in tropical regions.