Sea Urchins Can Create Underwater Deserts

Though they look like simple pincushions, sea urchins are powerful ecosystem engineers. When their predator populations drop, they graze so aggressively they leave behind barren, lifeless underwater wastelands.

These spiny creatures move across the seafloor using a complex system of tube feet and needles. While they primarily eat algae, their massive appetites can completely strip an area of kelp and marine life. These desolate regions are known as urchin barrens, which are often unable to recover without external help. By controlling these populations, predators like otters play a vital role in keeping our oceans lush and healthy.