As Sea Stars Die, New Worries About Urchins

Some urchins waste away, others come out of hiding as the fallout from sea star disease ripples along the California coast.

By Leslie Willoughby, National Geographic 


SANTA CRUZ, California—Along California's central coast, an unusual underwater scene is unfolding. Where sea urchins previously hid in cracks and crevices, they now carpet the seafloor. Yet a couple hundred miles away, in southern California, urchins are losing their spines and dying.

This emergence of urchins, as well as the mass mortalities to the south, are newly discovered phenomena that appear to be connected to a die-off of sea stars that scientists have called the largest marine disease outbreak ever recorded.

Effects of the sea star die-off seem to be reverberating along the California coast, altering the prey and predator relationships of urchins, sea otters,kelp, and even human anglers...

Find the full story with maps of where the disease is hitting the coast the hardest here:

Photo credits: Linsey Hesla