Summary: | The US Northeast Shelf (USNES) provides habitat for many economically and ecologically important fish species and is one of the most rapidly warming regions in the world. A common response from several fishes to warming has been poleward distribution shifts, potentially including the Northern stock of black sea bass (Centropristis striata). Black sea bass inhabit coastal waters along the USNES from (south to north) Cape Hatteras, NC to the Gulf of Maine during summer and migrate to the southern shelf-slope edge for the winter. Understanding the causes and implications of the distribution shift in black sea bass is important for fisheries management because state-specific quotas are based on regional biomass. Research on these impacts of ocean warming on fish species will help support proactiveness from fisheries management towards the changes in fish population dynamics and distributions, and avoiding future conflicts. Therefore, for my dissertation, I researched the impacts of ocean warming on black sea bass from the individual to population level with a focus on population dynamics and distribution extents as they relate to fisheries management. Chapter 2 used laboratory-based physiological experiments to determine optimal temperatures by measuring metabolic rates and hypoxia tolerance at a range of temperatures. Black sea bass could not acclimate to 30℃, and while 24℃ was technically the thermal optimum, measured as the temperature with highest aerobic scope, 24℃ was suggested to be the maximum tolerable temperature. This decision was determined based on Metabolic Index values reaching limiting values near 24℃, which suggested this temperature may not be optimal. The southern portion of BSB range can warm to >24℃; therefore, temperature is likely a dominant driver of recent distribution shifts, at least in the southern extent of their distribution. Chapter 3 investigated if black sea bass in the northern extent, that has currently been experiencing increasing biomass, utilized spawning strategies suitable ...
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