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Courtesy of the Aquaculture Program Research Report from HSWRI:

Ocean acidification, caused by elevated atmospheric carbon dioxide (CO2) being assimilate into coastal waters, is documented to result from anthropogenic processes (e.g. burning of fossil fuels). It is estimated that the increasing concentrations of atmospheric CO2 will result in higher oceanic levels of dissolved CO2, with subsequent lowering of seawater pH (this is often referred to as “ocean acidification”). In addition to coastal fluctuations in CO2 and pH, conditions of low pH are common in aquaculture settings where fish are raised at high densities in tanks. Elevated CO2 concentrations are of concern with regard to finfish health, growth and development. Some studies have documented effects of ocean acidification on invertebrates and bivalves, but limited research has been performed on finfish.

Hubbs-SeaWorld Research Institute has recently teamed up with researchers at USD to study the effects of elevated CO2 concentrations in the seawater environment and its effects on fish eggs and larvae. The USD research team includes Dr. Nathalie Reyns, Dr. Steven Searcy and graduate student Anthony Basilio (Figure 4). This study uses white seabass as a model species to examine the behavioral effects of ocean acidification on fish larvae; specifically documenting behavior and the larvae’s ability to capture prey successfully. After having learned how to raise and maintain white seabass larvae in a biosecure environment, Anthony is now beginning to mimic ocean acidification conditions by infusing CO2 at various levels into the water of larval tanks. Anthony will then record larval behaviors during feeding beginning at 3 days post hatch, and thereafter at regular age intervals. Feeding success, weight and length of larvae will be documented throughout the culture process to assess effects of elevated CO2 on larval growth and development. This research will lead to a better understanding of how fish larvae are affected by increased atmospheric and oceanic CO2 concentrations and the potential repercussions of future ocean acidification on marine fish populations.