THE VARIED ROLES OF SNAILS - National Universities Commission

females.. Self fertilization is a common mode of
reproduction and mating is often absent while ovposition
results from the transfer of stimulatory substances with
origin in the reproductive tract during mating. Snails are
hermaphrodites. Although they have both male and female
reproductive organs, they must mate with another snail of
the same species before they lay eggs. Some snails may act
as males one season and as females the next. Other snails
play both roles at once and fertilize each other
simultaneously. When the snail is large enough and
matures enough, which may take several years, mating
occurs in the late spring or early summer after several
hours of courtship. Sometimes there is a second mating in
summer. In tropical climates, mating may occur several
times a year. In some climates, snails mate around October
and may mate a second time 2 weeks later. After mating,
the snails can store sperm received for up to a year, but it
usually lays eggs within a few weeks. Snails are sometimes
uninterested in mating with another snail of the same
species that originated from a considerably distant place.
For example, some H. aspersa from southern France may
reject H. aspersa from northern France.
Snails need soil at least 2 inches deep in which to lay their
eggs. For H. pomatia, the soil should be at least 3 inches
deep. Keep out pests such as ants, earwigs, millipedes, etc.
Dry soil is not suitable for the preparation of a nest, nor is
soil that is too heavy. In clay soil that becomes hard,
reproduction rates may decrease because the snails are
unable to bury their eggs and the hatchlings have difficulty
emerging from the nest. Hatchability of eggs depends on
soil temperature, soil humidity, soil composition, etc. Soil
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