Mercaptans, particularly butyl mercaptan, are also produced by skunks and are part of that pungent odor.
I was very surprised that the invasion of the Asiatic clam was so overwhelmed by the invasion of the zebras. The succession to the Quaggas also is remarkable. It was thought, in the 80’s, that Corbicula would take over every environmentally favorable water body. It would be interesting to know how prevalent Corbicula is in its former territory - the Sacramento and Potomac River basins and other, similar locations. The Corbicula had been sold to fishermen as bait, and they tossed the leftovers into streams and lakes, enhancing the rate of spread.
Alas, I now work on cleanup of mining and petroleum waters and wastes and on water and sanitation in developing countries. I’ve been out of the mollusc game for a long time.
Ron