Many of us have heard the sickening crunch of a snail’s shell as we accidentally crush them whilst out walking or tidying the garden shed. If you have then you may have wondered if it spells the end for your unlucky garden friend.
Sadly the answer is probably yes. Snails can only repair minor damage to their shells, the comforting tale that snails can ‘move’ to a new spare shell is just a myth.
Much like our own finger nails a snail’s shell forms part of its body. Snails are born with their shells in place but at birth the shell is soft and unformed. This soft early shell soon hardens and grows with the snail throughout its adult life.As the snail grows it produces further soft shell material that hardens to further grow its defensive armour. The snail excretes the new shell material around the opening of its shell causing it to grow in a spiral, widening with the snail’s increasing body mass.
If this shell becomes significantly broken then the snail will die. Whilst they can repair small cracks and holes if the break is serious then they will die as the shell not only provides protection but also prevents the snail from drying out.
In captivity people have been known to use plasters and even normal sticking tape to hold minor broken shells together allowing the snail to fill and seal the cracks.
In one extreme case a vet in Israel carried out extensive repairs to a stricken snail gluing it’s shell together: