One seen via flashlight while walking along the water late at night, in water not much deeper than the fish itself.
Lots, some very large! The ones in the last photo are easily 4 inches across.
Mussel or oyster? This kind tended to be in flaky layers, not laid out all nice and identifiable like the scallop fossils.
This whole hill was a ridiculous graveyard of snails!
On the banks of Aliso Creek.
Bush not far from Aliso Creek.
Released a clear drop of fluid.
Lots entering a large hole in the ground.
Spines much less dense and yellow than: http://www.inaturalist.org/observations/4645875
Pads seemed larger also.
Shiny-leafed dune plant with stolons under the sand.
Big dead sea lion.
First three photos are one individual snail, next three are a different one. I think they're the same species.