Having just spent a week away, during which time I was searching for freshwater mussels (and finding very few) I note that on one island now almost entirely covered in vineyards that all mussels had vanished from all streams in every catchment.
Every 3 or 4 weeks they spray the vines with a copper compound to kill the likes of fungus. .... copper isn't good for aquatic invertebrates, the streams are almost dead, albeit crystal clear, and these streams head to the ocean. Copper is particularly nasty for cephs! Are vineyards contributing to the demise of aquatic inverts, and coastally, cephalopods? It's a research project that we'll look into in the not-too-distant future. It might change my attitude towards wine ....
Hmm. Unless this is a very recent change in grape-growing behavior, I'd be surprised, since there seem to be good populations of cephs near major wine producing regions like Napa, California and the Mediterranean... still, I'll be interested if you investigate... (And if you need an assistant to wander around Napa looking in streams and getting free samples from vineyards next time you're in the states, feel free to see if I'm available...)
I don't know enough about the mechanism to comment Mark; that's all. I seem to be stretched way too thin these days and don't have the time (and late in the eve, inclination) to extend myself too much further of late. Sad state of affairs!
When you come home late and tired, just enjoy the wine. There are so many things we can't enjoy at all anymore, and until the research is done, you might as well enjoy the wine. They aren't going to stop making it any time soon anyway.
Coincidentally there's an area right across the highway to the east from me here in north Fort Worth called Fossil Creek. All the signs have giant ammonite shells on them. I'm tempted to scout out the local creek beds, but I have no idea what the history of the area is. Even if they're ancient dead cephs, would be cool to find some.