Snorkel question - what are those green bubble things??

[Lindy]

Looking at Pickle's pictures reminded me of my own snorkel trips and have answered alot of my questions on identifying various sea creatures. One thing I haven't been able to figure out are those green bubble-like structures that you see attached to some of the rocks. They're hard, almost glass-like but fragile - I've tried to bring some to the surface to show others in my group but then tend to fracture if you try to pull them off the rocks. They look like they could be picked up but they are attached an the bottom of the sphere. I sure hope I haven't been disturbing some sort of egg casings or larvae!!!! Just
curious....

[Larry]

Not to spoil your fun. But I heard they were fish poop. I managed to bring one to shore once and locals were like 'ewwwww'.

[bevm]

Now that friggin' cracks me up!!! Who knew we're all swimming and snorkeling in water where fish poop??

[hugo]

Not sure what you mean from that description, but it doesn't sound like fish poop...
and if it is attached to the rocks, please, please, don't take it off...there are very good reasons for National Park regulations.

[hugo]

On reflection, I think you mean bubble algae--it was the glass- like part that had me fooled.Google it and see...

[California Girl]

The way I understand it, it's the SAND that's the fish poop!

[Lindy]

Yes, yes....that's it Hugo! Bubble algae or Ventricaria ventricosa also known as sea pearls or sailor's eyeballs. They can have a hard coating according to internet sources. They do not look organic at all and I thought at first that they were some kind of manmade objects and would not have attempted to pick them up if I'd known. Breaking them simply releases their spores.