The turquoise water of Hōnaunau Bay in Hawaii, an area popular with snorkelers and divers, is teeming with spiny creatures ...

This array of sea urchin skeletons reveals a diversity often hidden from view. The specimens in Hallan’s images—more than a thousand in total—are held at the Sea Urchin Science Centre and ...

In addition to posing a threat to swimmers, sea urchins in this popular snorkeling and diving spot in Hawaii are also harming ...

A healthy forest of giant kelp, in Monterey Bay. (Photo by Michael Langhans) In this urchin barren in Monterey Bay, grazing by purple sea urchins has removed kelp and other algae from the rocky reef. ...

Engineers are using the method by which sea urchin sperm find an egg in the ocean as inspiration ... 15 riveting images from the 2025 UN World Oceans Day Photo Competition 15 riveting images ...

The long-spined sea urchin—a fist-size ball of black defensive spines—is a crucial and common part of the Caribbean’s coral reefs. In 1983, a strange affliction all but wiped them out.

Sea algae could take over coral reefs after an unknown disease decimated sea urchin populations. ... Getty Images. Black sea urchins used to blanket the seabed off Israel and Egypt.