The Fragile Tree Snail (Samoana fragilis) was originally known as a widespread but uncommon species from Guam and Rota in the Mariana Islands. Currently, on Rota there is one small population (found in 2015). On Guam, the species was restricted to six sites in 1989, but all had disappeared by 1996. In 2007, a colony of 100 individuals was found and further populations were discovered in 2020. In the past, the population declined due to habitat loss and degradation and, on Guam, the introduced predatory Rosy Wolfsnail (Euglandina rosea). Now, the main threat is the introduced predatory New Guinea Flatworm (Platydemus manokwari). This species is assessed as Endangered because of its restricted range (area of occupancy is 32 km² and extent of occurrence is smaller than 3,000 km²), occurrence in fewer than five locations, and inferred continuing decline in population size due to introduced predators. In addition, the population size is no more than 300–400 mature individuals, with most occurring in one subpopulation and an inferred continuing decline in population size.

This species is endemic to Guam and Rota in the Marianas Islands, where it was recorded in 2020 from seven sites on Guam and one site on Rota. This species is considered to be present in 5 locations based on the proximity of the known sites to each other given that the invasive predatory species is present on both islands.

In 2020, this species was found in eight colonies, each estimated to hold 10–100 individuals. The total population is probably 300–400 individuals, possibly even less.

This species is found in woodland habitat, where it occurs on trees, usually in the canopy.

The main threat to this species is introduced predators. Historically, Rosy Wolfsnail (Euglandina rosea) caused major declines on Guam. It is now also threatened by New Guinea Flatworm (Platydemus manokwari), which has been on Guam since 1978 and on Rota since 1988. Historical habitat loss also caused population restriction in the past.

Many partulids were used in necklace making but no trade was recorded in this species.

No direct conservation actions have been taken for this species.