Rocky Intertidal Ecosystems

 

EXTREME LIFE ON THE ROCKS

The rocky intertidal ecosystem is a world of extremes – a marine zone that sits at the juncture of crashing ocean waves and rocky shorelines. It can take the form of exposed rocky cliffs, boulder rubble, wave-pounded rocky shelves, and sheltered rocky shores. Organisms living in this ecosystem are faced with extreme levels of disturbance inherent in this environment, including submersion, exposure to air, and being pounded by surf. Rocky Intertidal Ecosystems also happen to be one of the most frequently visited habitats for wildlife viewing, tide-pooling, and other coastal recreation.

LIVING ON THE EDGE

Rocky intertidal ecosystems are rocky shorelines that occupy the region between high and low tide. To withstand periodic exposure to air and wave forces, organisms are uniquely adapted to thrive in this challenging environment. These ecosystems are divided into zones, each one experiencing different levels of submersion and exposure to air, and include:

  • The upper (landward) end of the intertidal zone, dominated by barnacles, limpets, chitons, and other encrusting species;

  • The mid-intertidal zone, where fucoid algae and mussels provide structure and habitat; and

  • The low-intertidal zone is made up of kelps, fleshy seaweeds, and seagrasses.

LINKING ECOLOGY AND HUMAN USE

Rocky shores present unique opportunities and challenges to detect and interpret changes that may occur within marine protected areas (MPAs). Specially designed temporal and spatial monitoring plans are required to interpret the combination of human uses, coupled with complex and patchy species distribution, and frequent natural disturbances within this ecosystem. Due to the complex interactions, monitoring this ecosystem also provides an opportunity to interpret human use influences on the ecology of each region.