Distributed from Baja California to Alaska, the red sea urchin (Mesocentrotus franciscanus) is both ecologically and commercially important. As ecosystem engineers, red urchins control algal abundances in kelp forest ecosystems. They are also the primary urchin species harvested for gonads or “uni” in California. Recently, M. franciscanus abundance has declined dramatically due to overfishing in the last few decades; in addition, warmer water temperatures are thought to cause increased disease and mass mortality events. Despite its importance and vulnerability, little is known about M. franciscanus’ ability to respond to prolonged temperature stress.
Furthermore, marine heatwaves (MHWs) are predicted to increase drastically in frequency, duration, range, and intensity due to anthropogenic climate change. With such forecasts and red urchin populations already on the decline, it is important to determine if future generations can rapidly adjust their phenotypes for survival in future MHWs on the California coast. The question then arises: what is the impact of future MHWs on red urchins, and further can they be resilient to future heat stress events?
This project will assess how MHWs and food availability affect the gonad quality of adult red urchins and whether the thermal history of adult red urchins could alter the thermal tolerance of their progeny. Results will give insight into how commercially important marine invertebrates with planktonic larvae may fare in future oceans. Outcomes may also be utilized by stakeholders to predict the climate readiness of the fishery and help them respond to changing environmental conditions.