The Impact of Acute Salinity Exposure on Salinity Tolerance in Tigriopus Californicus (2024)

Undergraduates: Andrew Ahn, Ella Parry, Andy Hoang

Faculty Advisor: Christopher Willett
Department: Biology

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In previous work, it has been found that the intertidal crustacean Tigriopus californicus showed increased tolerance to heat following prior exposure to heat stress. With the interrelatedness between temperature and salinity in aquatic habitats becoming more crucial with global climate change, we hypothesized that repeated exposure to acute salinity would similarly increase tolerance in T. californicus to salinity stress. To explore this, T. californicus copepods were collected and divided into either “one time” or “two time” exposure groups, where the “one time” group faced a singular salinity stress event prior to testing, while the “two time” group faced two salinity stress events. Additionally, males and females from each treatment group were also tested to explore possible impact of sex on salinity tolerance. A respirometer was used to measure the oxygen usage of the copepods as a reflection of salinity tolerance. Linear modeling and statistical tests were applied to rates of oxygen consumption and revealed that prior exposures to acute salinity along with sex had no significant effect on oxygen usage in T. californicus. These findings suggest that previous salinity stress events do not impact salinity tolerance of T. californicus, which may reflect growing concern with marine life with expanding threat of climate change. However, these findings may not be completely representative of copepod tolerance in response to salinity since the sample size was small, and the relationship between respiration rate and tolerance is unknown.