How long can snails go dormant, sealing off their shell?

Snails have the ability to enter a dormant state, known as estivation, especially when faced with unfavorable environmental conditions such as extreme heat or drought. During this period, they can seal themselves off by creating a calcified mucus layer within their shell, which conserves moisture and protects them from desiccation.

The dormancy period can extend for several years, depending on the species and environmental conditions. It is not uncommon for certain snail species to remain dormant for 2 to 4 years, allowing them to survive until conditions improve. This remarkable adaptation highlights the resilience of snails in harsh environments. While some other durations are less accurate, the ability of many snails to withstand dormancy for an extended period confirms the correctness of the answer that indicates a range of 2 to 4 years.