Intertidal zones are competitive worlds where conditions can be immensely tough, but for species with the right adaptations these watery Wild Wests have much to offer.
Make a splash
The splash zone is the area just above where the water reaches at high tide. Constantly sprayed by breaking waves, this space suits species that thrive out of sea water but have a high tolerance for the salt left behind when it evaporates.
Lichens are common residents of the splash zone. These hardy organisms are actually formed of two partners that would otherwise need gentler conditions to survive: a fungus and an alga. The fungus gathers moisture and nutrients from its surroundings, while the alga produces energy through photosynthesis.
High and dry
The upper shore is the area at the limit of high tide. It's exposed for most of the day, enjoying only short periods under water. Residents must be able to combat desiccation, heat, and plenty of sunlight, as well as collision with breaking waves when the tide is in.
Only a few specialised seaweeds can live this far up the shore. Channelled wrack can survive up to eight days out of water thanks to the eponymous channels along its fronds - in fact it dies if submerged for too long! Spiral wrack, though not quite as hardy, can survive losing 80% of its water content. As it dries, it curls its fronds into spirals to conserve precious moisture.