Searching for seashells at low tide in the intertidal zone along the rocky and sandy coast of Brittany, France
Click on image for full size
Courtesy of Annette Pharamond
Life in the Intertidal Zone
The intertidal zone is the area along a coast that is underwater at high tide and above the water at low tide.
Creatures that live in the upper part of the intertidal zone are only covered with water during very high tides. Creatures in the lower part of the intertidal are only exposed to air during very low tides. Some plants, animals, and algae prefer to live in the upper intertidal, while others prefer the lower intertidal.
On rocky coasts, you can usually find slippery algae on the rocks. Other rocks might have a rough surface because they are covered with animals that have hard shells like barnacles and mussels. You might find sea urchins and sponges in places that are usually covered with water. There are sometimes small pools of water between rocks that remain even after the tide goes out. These are called tide pools and they are often filled with many different animals, plants, and algae.
Marshes can be found in areas that are protected from waves. They usually have soft mud, quiet water, and thick grasses. At low tide, the mud is exposed to the air. You can often find molluscs like clams, mussels, and oysters in and on the mud. You might also see crabs, fish, and shrimp. Tiny plants that are too small to see are in the mud too.
On sandy beaches, animals like clams live in burrows within the sand. If they are in their burrows, you might not see them. But you can often find seashells on the beach from clams that have died. Living in a burrow protects the animals from large waves that often crash along sandy beaches.
Shop Windows to the Universe Science Store!
The Summer 2010 issue of The Earth Scientist
, available in our online store
, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.
You might also be interested in:
Kingdom Plantae has almost 300,000 different kinds of plants. Plants are found all over planet Earth. They can live in fields, in swamps, in oceans and in the desert. They can live where it is hot and...more
An aquifer is the name for a layer of rock which is capable of holding a large amount of water. Some layers are better at holding water than others, for example a layer of sandstone can hold a good deal...more
Limestone is an example of a carbonate. Other examples of carbonates include calcite, dolomite, and marble. Limestone dissolves easily in rainwater, especially rainwater which is loaded with carbonic acid....more
The deep ocean waters are under pressure and are much colder than layers of the ocean which are closer to the surface. Dissolved carbon dioxide seems to be absent from the deep ocean water and as a result...more
Have you ever left a glass of water out for a long time? Did you notice that the water disappears after a few days? That's because it evaporated! Evaporation is when water passes from a liquid to a gas....more
The water at the ocean surface is moved by powerful wind. The wind is able to move the top 400 meters of the ocean. This moving water is called surface ocean currents. Surface ocean currents form large...more
Rivers are very important to Earth because they are major forces that shape the landscape. Also, they provide transportation and water for drinking, washing and farming. Rivers can flow on land or underground...more