Newcomb's Snail - Ecology

Ecology

Newcomb's snail is an obligate freshwater species. The details of its ecology, such as life span, reproductive cycle, and number of eggs/young, are unknown.

Newcomb's snail is active during the day.

Newcomb's snail probably shares life history similarities with other members of its family. Lymnaeid snails generally feed on algae and vegetation growing on submerged rocks. Snails attach eggs to submerged rocks or vegetation and larval stages do not disperse widely; the entire life cycle is tied to the stream system in which the adults live. Little is known about the biological or environmental factors affecting Newcomb's snail population size, however, important factors may include: annual, multi-year, or decadal changes in stream flows; severe weather, high flow, or channel-scouring events; and periods of prolonged drought. Snail dispersal both upstream and downstream within a stream system probably plays an important function in colonizing or recolonizing suitable habitat, particularly microhabitat protected from channel scour. Dispersal of Newcomb's snail between stream systems is likely infrequent because of their obligate freshwater habitat requirements; historic dispersal probably relied on long-term erosional events that captured adjacent stream systems. This life history differs greatly from the freshwater Hawaiian neritid snails (Neritina granosa, Neritina vespertina) that have marine larvae that migrate into and up streams following a period of oceanic dispersal. Most likely, the planktonic larvae of the neritid snails disperse across the oceanic expanses that separate the main Hawaiian Islands and can colonize streams on any or all of these islands. Newcomb's snail lacks this dispersal capacity.