Glowing Eggs on Myrtle Beach

So recently I spent a week at Myrtle Beach with my best friend and his family, and while walking the beach we discovered a lot of critters. I poked around on the net but so far I haven't found what this could be.

They were tiny, gelatinous eggs that, when you walked the beach at night, if you stepped on one, it glowed for just a second, then stopped. If you pushed it around some more, it glowed a bit more but eventually faded out. We first noticed it walking at night just north of the Grande Shores Resort, so I grabbed a flashlight and got Michelle to hold one of the eggs so I could photograph it, using my keychain-flashlight to illuminate it.

Then we made several attempts to coordinate squishing the eggs with clicking my camera's shutter to get them to glow long enough for my camera to pick up the light, which it did. I enhanced the image just a bit to bring it out. It seems to have a geenish/blue tint to it.

Here's another shot of it, for size comparison.
Michelle is a petite 14y/o, that's her thumb.

So I went back in the morning and took a couple more shots while I was shooting the sunrise.

If you wanna see a real closeup, CLICK HERE

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You can barely see some shape in the bottom right edge of it, a little yellow, like maybe an embryo of a fish or crustacean.... like that tiny dot at the end of the wormy yellow thing under the bubble might be an eye.

I asked a Myrtle Beach State Park ranger if she knew what it was and, not having seen it but obviously knowing a lot about the local ecosystems, she said maybe some bioluminescent phytoplankton. But looking at this, I'm wondering now if it isn't an egg. Maybe. Could be what I think is an eye could be just a fleck of dust - as tiny as this is. Those are grains of beach sand it's resting in to give you a better sense of scale.

I noticed all the shots seem to show that there's a bubble in each one -- whether it's air or a chemical that creates the bioluminescence when crushed and mixed with the rest of the organism, I don't know. It looks more like that little yellow pouch on the left side of that bubble would more likely be the source of the bioluminescence.

But the way that bubble bends the light like a convex lens (notice how the grains of sand appear smaller when you look through the bubble), it looks more like air, or a much less dense liquid than the matter surrounding it.

But if it is air, it explains why it floats and ends up on the beach instead of down in the ocean floor. The air bubble and/or the bioluminescence must have some evolutionary advantage. But I figure bioluminescence is more of an attractor than a repellent.

Maybe the bioluminescence is a residual trait (or one it uses advantageously as an adult) and the air bubble is the advantage that keeps it afloat -- so it stays in the daylight, and has a better chance of not attracting predators and getting eaten, like it would glowing down in the deeper, darker water.

Or the bioluminescence (which occurs only when crushed) is meant to 'freak' the predator out so it won't eat the rest of it's family. --- HA! or even better, acts like one of those explosive "dye bags" that explode all over bankrobbers to identify them, only this explodes all over the predator, making it easy to spot and avoid in the dark, or making it easier to spot by larger predators that might eat it before it eats the rest of them! Not likely, but weirder, more complex stuff happens in nature all the time!

I thought maybe it could be mole crab eggs, since mole crabs were all over the beach, but my research shows them as smaller, more orange, and carried under the mole crab's belly.

Anyway, it's interesting. If anyone who reads this knows what it could be please leave a comment.

UPDATE 8/19/2008:

I received an email from Myrtle Beach State Park about this.

Go here to view my updated blog