Dear Tom,
Have you read the book: Watching, from the Edge of Extinction by B. P. Stearns and S. C. Stearns
List Price: $30.00 Hardcover - 288 pages (April 1999) Yale Univ Pr; ISBN: 0300076061
This book has a very informative chapter on extinction of Hawaiian land snails.
Marine molluscs are in general very resilient against extinction with only one scientifically known
species that was confirmed (gone extinct), while land snails and freshwater species are very fragile.
It is rather interesting to note that your freshwater environment is under threat by a small freshwater
mussel of foreign origin that is very invasive. In my class of conservation of marine resources and
environment, I use these examples for teaching.
Masashi Yamaguchi