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Purple Sea Urchin



A small, possible juvenile sea urchin, with grey/purple spines; bright, almost luminous bases and a dark centre. Main body is about 2cm in diameter.


Photographed on the shallow limestone flats, Utuko Reef, Western Niue, in about 3cm of water at low tide. Tucked sideways into a rocky crevasse


According to locals, there was a huge die back of sea urchins last year, almost all of the adults were washed up dead and dying on the beach. However, eggs were left behind. I didn't see a mature sea urchin in a week of snorkeling in Niue, but these small, juvenile ones seem to be making a come back.

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remkinloch 4 years ago

Thanks Mark. Only saw a few of these but at low tide they were barely in the the water. The only way I could get a photo was to rest the camera just below the surface and shoot - no zoom! Hence only up close photos!

Mark Ridgway
Mark Ridgway 4 years ago

Excellent spotting. It looks like they have internal lighting.

remkinloch 4 years ago

Thanks, was meant to be in Other :)

DanielePralong 4 years ago

Great spotting from a fantastic location! I relocated it from Plants to Other for you.

Leuba Ridgway
Leuba Ridgway 4 years ago

Great spotting & information. Thanks.

Spotted by


Spotted on Aug 6, 2017
Submitted on Aug 10, 2017

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