Domoic Acid?

This Sunday I shelled my two crabs fresh.  The first crab had two large black bladders.  Yech. I've never seen these before. But, this is my first time shelling crab fresh.  I shelled the second crab and no bladders.  I pulled the bladders out of the sink and took this photo.

What to do with that one crab?  Is this common?  Has anyone else encountered this?

Here's a Hojoman link to last years Domoic Acid.  Maybe it's related?
http://www.norcalkayakanglers.com/index.php?topic=59567.msg671733;topicseen

For size comparison, you can see Rapala on the knife blade.