On the basis of these data from the 6 existing populations of Newcomb's snails can be estimated a total population of approximately 6,000 to 7,000 individuals. The great majority of these snails, perhaps over 90%, were located in the two populations at Kalalau and Lumaha`i. Terrain occupied by Newcomb's snail populations is remote and extremely rugged. Three of the six populations can only be visited using helicopter transport, although the Kalalau Stream population potentially could be accessed in summer months with boat support and strenuous hiking. Because of the difficulty in accessing the sites, no comprehensive Newcomb's snail population census has been undertaken since 1995, and changes to the population since that time remain undocumented.