A new study co-authored by Dr. Nathan Spindel of Moss Landing Marine Laboratories and published in Communications Biology (Nature Portfolio) reveals how sublethal ocean warming can undermine the reproductive capacity of the purple sea urchin (Strongylocentrotus purpuratus), a dominant herbivore in California’s kelp forests.
Using controlled mesocosm experiments that simulated historic El Niño events, the team demonstrated that even moderate heatwaves can sharply suppress gametogenesis, especially in females, leading to recruitment collapses observed in long-term field data. The research highlights that population viability can falter well before lethal thermal limits are reached, emphasizing the need to integrate sublethal physiological stress into models of climate vulnerability and kelp forest resilience.