Algae

Algae

Algae are near the bottom of the tidepool food web. They use photosynthesis to capture light energy from the sun. Large algae cling to the rocks and seafloor with root-like holdfasts. Algae range in size from single-celled organisms to 150-foot-long giant kelp. Rockweed algae grow to 10 inches in the intertidal zone. They mark the high-tide line like “bathtub rings.” Coralline algae, once mistaken for coral, are crunchy due to calcium carbonate in their cell walls. They range from flat to three inches in height.