Sea Grant: Combating Urchin Barrens with Aquaculture

Combating urchin barrens with aquaculture

Author: Helaina Lindsey, Student, Moss Landing Marine Laboratories

June 28, 2019


"California’s kelp forests are currently facing a major threat: deforestation.

The root of this issue can be attributed to small, spiny invertebrates – purple sea urchins (Strongylocentrotus purpuratus). When urchins do not face predation pressures, their populations multiply, and they devour the foundation of kelp forests. When too many urchins are present, they prevent growth of canopy forming kelp, turning a beautiful and diverse kelp forest into a wasteland – also known as an urchin barren. These barrens don’t provide any of the benefits of a kelp forest, such as harboring endangered or commercially important species, sequestering carbon, preventing shoreline erosion, and oxygen production."

On the left, a vibrant California kelp forest. On the right, an urchin barren. Credit: NOAA