UC San Diego

The red rock shrimp, Lysmata californica, is a key species in Southern California's shallow coastal ecosystems where it faces environmental challenges due to seasonal and long-term changes in ocean pH and temperature. These environmental changes could potentially affect the shrimp's molting process by extending postmolt recovery and affecting mortality rates through altering behaviors. This study investigates the impacts of ocean acidification (OA) and warming (OW) conditions on key behaviors of L. californica during postmolt. Shrimp were exposed to a combination of pH (8.1 and 7.7) and temperature (12°C and 15°C) conditions for 50 days, during which we assessed feeding, cleaning behavior, and startle responses at two critical times postmolt (<15 hours and 5 days post-ecdysis). Our findings reveal that reduced pH significantly delays initiation of feeding postmolt and diminishes food consumption postmolt, while warmer temperature increases overall food consumption. Additionally, reduced pH conditions deterred cleaning behavior, whereas warmer temperature enhanced it. There were no discernible effects on startle responses across treatments postmolt. These results demonstrate that OA and OW conditions can alter important behaviors of L. californica during the critical postmolt period, temporarily disrupting their roles within mutualistic symbioses under ongoing climate change.