Estivation or aestivation (from Latin aestas, summer), also known as "summer sleep", is a state of dormancy somewhat similar to hibernation. It takes place during times of heat and dryness, the hot dry season, which is often but not inevitably the summer months.
Invertebrate and vertebrate animals are known to enter this state, in order to avoid damage from high temperatures and the risk of dehydration. Both terrestrial and aquatic animals undergo estivation.
The habit of climbing up vegetation in order to estivate has caused more than one introduced snail species to be declared a agricultural nuisance: a crop pest.
To seal the opening to their shell in order to prevent water loss, pulmonate land snails secrete a membrane called an epiphragm, which is made of dried mucus. In certain species, such as Helix pomatia, this barrier is reinforced with calcium carbonate, and thus it superficially resembles an operculum, except that it has a tiny hole to allow some oxygen exchange.
Some amphibians estivate during the hot dry season by moving underground where it is cooler and more humid. The California red-legged frog may estivate to conserve energy when its food and water supply is low.
US Patent Issued to Estivation Properties on Dec. 25 for "Flange Package for a Semiconductor Device" (Arizona Inventors)
Dec 26, 2012; ALEXANDRIA, Va., Dec. 26 -- United States Patent no. 8,338,937, issued on Dec. 25, was assigned to estivation Properties...