Award: OCE-1656923

The objectives of the study were to investigate how the distribution of fish and invertebrate species have changed over the last 35 years in the northwestern Gulf of Mexico and to determine the extent to which the changes are attributable to climate change. The results from the study demonstrated that the diversity of fish and invertebrate species has generally increased (Fujiwara et al. 2019; Pawluk et al. 2021). The increased diversity resulted from the expansion of the species associated with warmer water and the retraction of the species associated with colder water. Because more species are in lower latitudes than higher latitudes, the northern shifts in the distribution of species resulted in increased species diversity at any given location along the coast. However, the shifts in the distribution of the species are not happening to all species in the same way. For example, the prevalence of invertebrate species is increasing faster than fish species. The species that spawn in winter tend to exhibit decreasing trend, and those spawn in spring and early summer tend to exhibit an increasing trend. Longer-lived species also tended to be affected by temperature more. These findings represent major steps toward understanding the mechanisms behind the tropicalization of estuarine communities in the northwestern Gulf of Mexico. The results from the study have broader impacts on marine natural resource management. The ongoing significant changes in species composition mean that the available species for both commercial and recreational fisheries will change in the future. For example, increased availability of invertebrates relative to finfish is expected. It is also known that the level of production of fisheries depends on the life history types of target species (Fujiwara 2012); therefore, differential effects of tropicalization on fishes with different life-history types are expected to have significant impacts on future fishery production. The study also contributed to capacity building in science. The project directly funded three students: one undergraduate student, one M.S.-level graduate student, and one Ph.D.-level graduate student. They successfully graduated and have continued to the next steps of their scientific careers. The project specifically recruited those with excellent credentials but lacking other opportunities. Two of the students happened to be under-represented minorities, and all the three students are women. Therefore, the project contributed to increasing the diverse workforce in science. Fujiwara, M., F. Martinez-Andrade, R. J. D. Wells, M. Fisher, M. Pawluk, and M. C. Livernois. 2019. Climate-related factors cause changes in the diversity of fish and invertebrates in the subtropical coast of the Gulf of Mexico. Communications Biology 2: 403. https://doi.org/10.1038/s42003-019-0650-9. Pawluk, M., M. Fujiwara, and F. Martinez-Andrade. 2021. Climate effects on fish diversity in the subtropical bays of Texas. Estuarine, Coastal and Shelf Science 249. https://doi.org/10.1016/j.ecss.2020.107121. Fujiwara, M. 2012. Demographic diversity and sustainable fisheries. PLoS One 7: 14. https://doi.org/10.1371/journal.pone.0034556. Last Modified: 12/18/2021 Submitted by: Masami Fujiwara