Twenty-eight percent (28%) of the snails are imperiled to some extent. However, little is known about life history, habitat requirements, current distribution, and other factors that may limit population numbers. A limited amount of work has been done at the Center for Mollusk Conservation (which currently cultures and propagates freshwater mussels and snails) to propagate a few species of snails (examples include Lithasia and Pleurocera).
For more information, see Johnson, P.D., A.E. Bogan, K.M. Brown, N.M. Burkhead, J.R. Cordeiro, J.T. Garner, P.D. Hartfield, D.A.W. Lepitzki, G.L. Mackie, E. Pip, T.A. Tarpley, J.S. Tiemann, N.V. Whelan, and E.E. Strong. 2013. Conservation Status of Freshwater Gastropods of Canada and the United States. Fisheries 38(6): 247-282.