Jeff Rotman / Wolf eel (Anarrichthys ocellatus) eating Red Sea Urchin (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean.

Jeff Rotman / Wolf eel (Anarrichthys ocellatus) eating Red Sea Urchin (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean.

Floris van Breugel / Giant Red Sea Urchins (Strongylocentrotus franciscanus) Purple sea urchins (Strongylocentrotus purpuratus) and Sea Anenomes (Anthopleura) underwater, in tide pools along Californian coastline, USA.

Fred Bavendam / Purple Sea Urchin (Strongylocentrotus purpuratus) and Red Sea Urchin (Strongylocentrotus franciscanus) group, Channel Islands, California

Fred Bavendam / Green Sea Urchin (Strongylocentrotus droebachiensis) group and one Red Sea Urchin (Strongylocentrotus franciscanus), Quadra Island, British Columbia, Canada

Richard Herrmann / Red Sea Urchin (Strongylocentrotus franciscanus) and Purple Sea Urchin (Strongylocentrotus purpuratus) feeding on Southern Sea Palm (Eisenia arborea) creating urchin barren, Santa Cruz Island, Channel...

Pascal Kobeh / Colony of Red sea urchins (Strongylocentrotus franciscanus) at the feet of Bull kelps (Nereocystis luetkeana) Vancouver Island, British Columbia, Canada. Pacific Ocean.

Franco Banfi / Giant red sea urchin (Strongylocentrotus franciscanus) Vancouver Island, British Columbia, Canada, Pacific Ocean

Pascal Kobeh / Underwater reef covered with a colony of Red sea urchins (Strongylocentrotus franciscanus), Alaska, USA, Gulf of Alaska. Pacific ocean.

Jeff Rotman / Close-up of Metridium Anemones (Metridium farcimen) and Red Sea Urchins (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean

Jeff Rotman / Spines of Red Sea Urchin (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean

Jeff Rotman / Spines of Red Sea Urchin (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean

Jeff Rotman / Wolf eel (Anarrichthys ocellatus) eating Red Sea Urchin (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean.

Jeff Rotman / Wolf eel (Anarrichthys ocellatus) eating Red Sea Urchin (Strongylocentrotus franciscanus). Queen Charlotte Strait, British Columbia, Canada, North Pacific Ocean.

Norbert Wu / Red Sea Urchin (Strongylocentrotus franciscanus) and brittlestars, Campbell River, Vancouver Island, British Columbia, Canada

Fred Bavendam / Sea Star (Mediaster aequalis), California Sea Cucumber (Parastichopus californicus) and Red Sea Urchin (Strongylocentrotus franciscanus), British Columbia, Canada

Fred Bavendam / Red Sea Urchin (Strongylocentrotus franciscanus) in urchin barren, Vancouver Island, British Columbia, Canada

Doug Perrine / Spiny / Piked dogfish {Squalus acanthias} with Red sea urchins {Strongylocentrotus franciscanus} Quadra Island off Vancouver Island, Discovery Passage, British Columbia, Canada. Note - also known as...

Doug Perrine / Spiny / Piked dogfish {Squalus acanthias} with Red sea urchins {Strongylocentrotus franciscanus} and orange sea pen {Ptilosarcus gurneyi} Quadra Island off Vancouver Island, Discovery Passage, British...

Doug Perrine / Spiny / Piked dogfish {Squalus acanthias} with Red sea urchins {Strongylocentrotus franciscanus} Quadra Island off Vancouver Island, Discovery Passage, British Columbia, Canada. Note - also known as...

Norbert Wu / White Sea Urchin (Lytechinus anamesus) group attack and feed on a larger Red Sea Urchin (Strongylocentrotus franciscanus), southern California

Richard Herrmann / Red Sea Urchin (Strongylocentrotus franciscanus) group feeding on Giant Kelp (Macrocystis pyrifera) creating urchin barren, Santa Cruz Island, Channel Islands, California

Shane Gross / Red sea urchins (Strongylocentrotus franciscanus) gathered on the seabed, Barkley Sound, Vancouver Island, British Columbia, Canada.

Shane Gross / Purple sea urchins (Strongylocentrotus purpuratus) and Red sea urchins (Strongylocentrotus franciscanus) on seabed, Barkley Sound, Vancouver Island, British Columbia, Canada.

Shane Gross / Red sea urchin (Strongylocentrotus franciscanus) close up detail of spines and tube feet, Vancouver Island, British Columbia, Canada, Pacific Ocean.

Shane Gross / Red sea urchin (Strongylocentrotus franciscanus) close up detail of spines, Browning Pass, Queen Charlotte Strait, Vancouver Island, British Columbia, Canada.

Shane Gross / Painted anemone (Urticina crassicornis) eating a Red sea urchin (Strongylocentrotus franciscanus) on rock wall, Vancouver Island, British Columbia, Canada, Pacific Ocean.

David Hall / Marine invertebrates including Crimson anemones (Cribrinopsis fernaldi), Painted anemones (Urticina crassicornis), Red soft coral (Gersemia rubriformis), Red sea urchins (Strongylocentrotus franciscan...

David Hall / Puget sound king crab (Lopholithodes mandtii) and Red sea urchins (Strongylocentrotus franciscanus), Deserter Group, Queen Charlotte Strait, British Columbia, Canada. September.