Ocean temperature shapes marine life in ways both obvious and subtle — it affects metabolism, survival, and ultimately how many fish, invertebrates, and other organisms a stretch of ocean can support. Understanding that relationship is key to predicting how ecosystems respond as the ocean keeps warming.
Early in my career, I studied how temperature shapes shallow-water marine life around Isabela and Fernandina, the westernmost Galápagos islands. This region is unusual: strong upwelling brings cold, nutrient-rich water to the surface, supporting cold-water species found nowhere else nearby, including penguins and flightless cormorants. I found that different parts of the region respond to temperature differently — communities in a deep channel were most sensitive to vertical temperature differences, while communities nearer the equatorial current responded more to seasonal swings.
Later, with colleagues, I looked at how temperature and fishing pressure together affected two economically important species, sea cucumber and spiny lobster. After accounting for fishing itself, we found warmer sea temperatures were followed, a year or two later, by higher catches of both — most visibly after the strong 1997–98 El Niño (Defeo et al., 2013).
Defeo, O., Castrejón, M., Ortega, L., Kuhn, A., Gutiérrez, N., & Castilla, J. C. (2013). Impacts of Climate Variability on Latin American Small-scale Fisheries. Ecology and Society, 18(4).
Edgar, G. J., Banks, S., Fariña, J. M., Calvopiña, M., & Martínez, C. (2004). Regional biogeography of shallow reef fish and macro‐invertebrate communities in the Galapagos archipelago. Journal of Biogeography, 31(7), 1107-1124.
Kuhn, A.M. (2010). Influencia de la temperatura del mar sobre comunidades rocosas submareales de la Reserva Marina de Galapagos. Tesis para la obtencion del titulo de Licenciatura en Oceanografia. Escuela Politecnica del Litoral. Guayaquil – Ecuador.
Angela M. Kuhn 