Climate change effect on Octopus maya (Voss and Solis-Ramirez, 1966) suitability and distribution in the Yucatan Peninsula, Gulf of Mexico: A correlative and mechanistic approach

Fisheries play critical roles in food supply and income for human communities worldwide. Unfortunately, the fishery distribution have been changing due to anthropogenic climate change (CC). In this sense, this study analyses were directed to predict the suitability and distribution of red octopus (Octopus maya), an endemic and commercially important species of the Yucatan Peninsula (YP) in Mexico under different CC scenarios. For this purpose, a correlative (CNM) and mechanistic (MNM) niche models based on temperature and salinity and on metabolic scope, respectively, were projected to different Representative Concentration Pathway (RCP) scenarios (2.6, 4.5, 6, 8.5) for the 2040-2050 and 2090-2100 periods. The CNM results suggest that red octopus suitability and potential distribution (PD) could be slightly reduced for the RCP 2.6 scenario. Whereas, RCP 4.5 shows higher suitabilities at the northern region of the YP, which is characterized by a seasonal upwelling which could act as climate refugia. In contrast, a significant suitability and PD reduction occurs during 2090-2100 for the RCP 6 and 8.5 scenarios. On the other hand, MNM indicates the red octopus could retain most of its PD except for the most catastrophic scenario, finding climate refugia north of the YP and deeper waters. Overall, the CNM is more pessimistic than MNM regarding forecasts. Differences between outputs could be based on the MNM using a single variable as proxy to a multivariate niche and the statistical weight of surface environmental variables in the CNM compared to MNM, which considered only bottom temperature data. In addition, coastal data may be overrepresented, which may bias the CNM. Regardless of the differences in the results, both approaches usually predicted suitability reduction in all RCP scenarios showing that temperatures of similar to 30 degrees C are detrimental for the red octopus. Assuming that a relationship between abundance and the niche suitability exists, landings in the region will be reduced and less accessible for small-scale fisheries, which is especially important since Mexican regulations assume this species will benefit from CC.

Automated summary

This study used two niche models to predict the suitability and distribution of the red octopus in the Yucatan Peninsula under different climate change scenarios. The results suggest that the suitability of the red octopus may be slightly reduced in the future, with potential impacts on fisheries in the region.