Snail reproduction is fascinating, complex and attuned to the natural rhythms of nature.
With more than 60,000 species worldwide, from mountain tops to the volcanic vents in the deep ocean, you can imagine that the diversity of breeding and reproductive behaviors and methods is equally as varied.
Heliciculturists are fortunate that, except for small variations among species and environmental conditions, reproduction of edible snails is relatively similar.
We are only concerned here with the terrestrial, pulmonate, hermaphroditic gastropods. Translated, this means they are all land dwelling, air-breathing snails that have both male and female reproductive organs. They are able to mutually mate with one another and both can produce fertile eggs.
While the mating behaviors and reproductive proclivities of individual snails vary, there are generalities that can be outlined.
Once or twice per year, depending on environmental factors, snails with begin mating. This consists of a lengthy courtship display where snails will intertwine their bodies in (at least to our eyes) erotic, intermingling dances. Once mating begins, which can last many hours, each snail may shoot a calcareous (calcium) dart, popularly called a “love dart” into its partner. While the exact reason for these darts has been debated, current thoughts are that it helps stimulate the partner to mating and potentially increases the amount of sperm absorbed. You can read a much more detailed, interesting and scholarly description by Dr. Ronald Chase of Canada’s McGill University.
Once a successful transference of sperm occurs, if conditions are ideal, the snails result are fertilized eggs, usually around 20-30, which are usually laid in shallow holes dug into the soil. These eggs must remain moist and then, in 3-4 weeks, hatch out into exact miniature replicas of the parents, complete with a thin, one-whorled shell. The babies are completely independent of parental care, immediately begin feeding on microscopic and/or decaying plant material. As they grow, the shell grows with them, adding whorls as the body inside grows. If you examine a shell, you may see small concurrent ridges that indicate the growth pattern.
Different species will grow at slightly different rates and of course, growth will depend on surrounding resources that are available and climatic conditions. But in general, snails reach breeding age around 8 months to a year and may live several years, with H. pomatia living up to 30 years. Giant African land snails may live even longer.