Beaches, Estuaries, and Coral Reefs

S1 E4: Beach organisms exist with the constantly changing winds, waves, and tides (sometimes underwater, sometimes fully exposed to the air). Life in estuaries, where rivers meet the oceans, face constant fluctuations in environmental salinity. And hard corals are continually pummeled by wave action. Yet each of these physically challenging environments can be diverse and fecund ecosystems.