Warmth, and OA, and Hypoxia, Oh My! Interactions of simulated climate change on the metabolism of coastal species

Gail Schwieterman1, Daniel P Crear2, Danielle Lavoie3, Brooke Anderson4, James Sulikowski5, Peter Bushnell6 and Richard Brill2, (1)Virginia Institute of Marine Science, Gloucester Point, VA, United States, (2)Virginia Institute of Marine Science, Gloucester Point, United States, (3)Roger Williams University, Bristol, RI, United States, (4)University of New England, Biddeford, United States, (5)Arizona State University, Tempe, United States, (6)Indiana University South Bend, South Bend, United States
Understanding how rising temperatures, ocean acidification, and hypoxia affect the performance of coastal fishes is essential to predicting species-specific responses to climate change. Although a population’s habitat influences physiological performance, little work has explicitly examined the multi-stressor responses of species from habitats differing in natural variability. Here, clearnose skate (Rostaraja eglanteria) and summer flounder (Paralichthys dentatus) from mid-Atlantic estuaries, and thorny skate (Amblyraja radiata) from the Gulf of Maine, were acutely exposed to current and projected temperatures (20, 24, or 28 °C; 22 or 30 °C; and 9, 13, or 15 °C, respectively) and acidification conditions (pH 7.8 or 7.4). We tested metabolic rates and hypoxia tolerance using intermittent-flow respirometry. All three species exhibited increases in standard metabolic rate under an 8 °C temperature increase (Q10 of 1.71, 1.07, and 2.56, respectively), although this was most pronounced in the thorny skate. At the lowest test temperature and under the low pH treatment, all three species exhibited significant increases in standard metabolic rate (44–105%; p < 0.05) and decreases in hypoxia tolerance (60–84% increases in critical oxygen pressure; p < 0.05). This study demonstrates the interactive effects of increasing temperature and changing ocean carbonate chemistry are species-specific, the implications of which should be considered within the context of habitat.