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Red sea urchin

Mesocentrotus franciscanus


Covered in sharp spines the Red sea urchin diet consist of seaweed and alga. In a study from Oregon State University in 2009 it was concluded that the Red sea urchin can live to over 100 years old, and some may reach 200 years or more in good health with few signs of age.


Spotted in tidal pools at Tongue Point. Found in the northeastern Pacific Ocean from Alaska to Baja California. It lives in shallow waters from the low-tide line to greater than 100 m (330 ft) deep, and is typically found on rocky shores sheltered from extreme wave action.

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Brian38 a year ago

Thank you very much Neil.

Neil Ross
Neil Ross a year ago

I had no idea they had such longevity. That is totally flabbergasting! It looks so nasty, so perhaps no one wants to tangle with it? Wonderful spotting and photos, Brian. Congrats on your SOTW nomination too.

Brian38 a year ago

Thank You Daniele for being nominated.

DanielePralong a year ago

Your spotting has been nominated for the Spotting of the Week. The winner will be chosen by the Project Noah Rangers based on a combination of factors including: uniqueness of the shot, status of the organism (for example, rare or endangered), quality of the information provided in the habitat and description sections. There is a subjective element, of course; the spotting with the highest number of Ranger votes is chosen. Congratulations on being nominated Brian!

Brian38 a year ago

Thanks Mark. They certainly have a curious existence. The Purple sea urchins were everywhere. I'll have a spotting for them soon.

Mark Ridgway
Mark Ridgway a year ago

..I wonder if those purple spines below it are related.

Mark Ridgway
Mark Ridgway a year ago

Great spotting Brian. I hope they find plenty to occupy themselves for those 200 years. :-D

Spotted by

Washington, USA

Spotted on Apr 20, 2019
Submitted on Apr 24, 2019

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