The California Horn Snail (Cerithidea californica), or Caracol de coño in Spanish, sometimes has to deal with the threat of drying out at low tide. Its shell has a special trapdoor called an operculum (pronounced oh-PER-cue-lum). This seals the snail safely inside the shell and keeps it from drying out when water levels are low. 

This snail is extremely tolerant of estuarine conditions (extremes in salt and fresh water), being able to survive for many days in fresh water. It feeds mostly on algae, diatoms (a microscopic form of algae), and decaying organic matter. Predators that feed on the California Horn Snail include Killifish, crabs, and mudflat birds. 

To see California Horn Snails in their natural habitat, please visit the Tijuana River National Estuarine Research Reserve just 15 miles from the Museum.

PHOTO CREDIT: Julio Lorda