World Economic Forum: How otters, urchins and kelp help to gauge the fragility of ecosystems
Scientists investigating declines in California’s kelp forests credit otters with helping to protect kelp - a species of seaweed - through their fondness for eating sea urchins. But not all urchins are equal to the otters, which zone in on the healthy nutritious ones and leave others behind.
Joshua Smith, a graduate student of the University of California, Santa Cruz (UCSC), started investigating the kelp forests in 2014. He wanted to know why patches of kelp were able to survive on the seafloor alongside completely barren areas covered in purple sea urchins.