
A new study of red sea urchins, a commercially valuable species, investigated how different populations respond to changes in their environments. The results show that red sea urchin populations in Northern and Southern California are adapted to their local conditions but differ in their vulnerability to the environmental changes expected to occur in the future due to global climate change and ocean acidification.
The new findings, published January 20 in Science Advances, indicate that red sea urchin populations in Southern California may be more vulnerable to climate change than those in Northern California. Although the sea urchins in Southern California are already adapted to warmer conditions, the researchers suspect that further warming of their environment may be more than they can tolerate.
“Red sea urchins from the Southern California population were much more sensitive to environmental changes than those from Northern California, and we think that is likely because they are already closer to some kind of thermal limit,” said senior author Kristy Kroeker, professor of ecology and evolutionary biology at UC Santa Cruz.
First author Emily Donham led the study as a UCSC graduate student and is now a postdoctoral scholar at UC Santa Barbara. “Red sea urchins are an important fishery species along our coast, so understanding how they are likely to be impacted by climate change is very important,” she said.
The study looked at the effects of three key environmental variables in the sea urchins’ coastal habitat: water temperature, dissolved oxygen, and pH (a measure of ocean acidification). Climate change driven by increased carbon dioxide in the atmosphere is warming the oceans and reducing oxygen levels in the water, while increased absorption of carbon dioxide by seawater leads to ocean acidification.
…
Tim Stephens, UC Santa Cruz, 20 January 2023. Press release.