Fire Urchins Spawning

[klausi]

Last week I was lucky enough to witness a spawning event of the fire urchin, Astropyga radiata, during a night dive in Negros Island, Philippines. The animals - large urchins, probably 25+ cm in diameter, were grouping in the sand at about 12 meters, and released significant amounts of gametes every few minutes. They huddled, and occasionally even climbed on top of each other. There were probably ~ 20 of them around.

I feel really lucky that I get to dive spots where this happens all the time, and I am not sure how well these spawning aggregations of this species are documented yet.

The video is here, spawning starts at 0:55