Prymnesium parvum (golden alga) is a toxin-producing, euryhaline species responsible for fish-kills worldwide. In Texas, toxic blooms occur in inland brackish waters but, for reasons unknown, not in high-salinity coastal environments. Information on the ability of inland strains of golden alga to adapt to high salinity would enhance our understanding of its geographic distribution and may also provide insights on reasons why it has failed to invade coastal areas, and how to keep it that way. The purpose of this study is to characterize the growth potential of golden alga in high-salinity water of different ionic composition over multiple generations. This study constitutes the master thesis of a unit graduate student (Emily Richardson) and is being supported by Texas Tech University and Texas Parks and Wildlife Resources. The information obtained may improve an understanding of salinity as driver of golden alga distribution and inform management efforts to limit its further expansion, especially into coastal waters.