Oceans and the creatures living in them face significant challenges in the future as a result of global climate change. Together, ocean warming and ocean acidification (an increase in ocean pH due to the absorption of atmospheric carbon dioxide) present a "double jeopardy" situation for marine organisms, challenging many aspects of their biology from reproduction to growth and perhaps even survival. Since the conditions in the oceans will change rapidly (leaving little time for adaptation), it is a critical priority to study the tolerances of today's marine organisms, because they and their offspring will be the ones facing the consequences of climate change in their marine habitat.
The goal of this project is to study an early developmental stage of the purple sea urchin (Strongylocentrotus purpuratus) and investigate how the larvae, at swimming and feeding stage, will respond to the simultaneous change in temperature and pH (ocean acidification). After larvae are raised in the laboratory in seawater conditions that mimic the projected pH and temperature of future oceans, the investigators will measure oxygen consumption, characteristics of their metabolism such as fat content, and examine how their genes are activated in response to the stress of higher temperatures and more acidic pH conditions. The outcomes of this research projects and resources for teachers and students in classrooms will be made available through http://hofmannlab.msi.ucsb.edu/.
Although sea urchins may not be as familiar to the general public as salmon or oysters, they are an ecologically and economically important species on the West Coast of the United States. For example, the sea urchins on the California coast support an important wild fishery; in 2008, the catch from sea urchin diving had a value of ~$10 million in California alone. As grazing herbivores, sea urchins are important to healthy coastal marine ecosystems. The sea urchin is a excellent study system, allowing the use of modern research tools to illuminate the implications of climate change for important human concerns such as food sources, fisheries that provide food and jobs, and healthy marine ecosystems.
