Monday, March 24, 2008


The Intertidal zone sits along the oceans edge. The environment is very rocky.This environment is very unique because the water level changes constantly. This is caused by the high and low tides throughout the day. Because the waves are very strong during high tide, only animals who are adapted to these strong tides can survive in the intertidal zone.

Fun Facts


  • There are intertidal zones along the coasts all over the world.
    It is rich with many nutrients and plenty of oxygen.
  • The temperature ranges from the regular temperature of water to air temperatures that can vary from below freezing to scorching hot.
  • The salinity is much higher in the intertidal zone because salt water gets trapped in rocks, when the water evaporates it leaves behind many salt deposits.
  • In California, tidepools are protected by law. Anyone caught removing or harming tidepool life may be fined as much as $500.
  • As the waves crash down, they carry food necessary for survival of the tidepool animals. Each wave carries a plankton soup which is one of the the main diets of a mussel or barnacle. Also, dead plants and animals wash into the tidepool feeding many animals, like hermit crabs, shore crabs, sea gulls and even anemones.
  • Tide pools may be formed at low tide when water is trapped in hollows. Under certain conditions, quicksand may be formed.
  • Recently proven the key to the barnacles stick is actually salt. The creatures have a special bottom to them and when the salt water comes intact with itit creates a natural solution. The solution substance is incredibly strong and sticky, like glue, allowing the barnacle to stick to surfaces.

From this experiment, you have seen evaporation. The main idea we want you to go away with is that evaporation happens constantly in the Intertidal Zone, and that when evaporation happens, salt is left behind. Tide pools can also contain lots of salt when the water from the tide pool goes away. Salt will stay in rocks or "in other animals" so animals have to have ways to adapt to this. They adapt by ways such as having a hard shell (like crabs do) that keep salt out of their shells and away from their bodies!

Pictures


These are some pictures

of the intertidal zone.



How do Animals Survive?


Animals in the Intertidal Zone must survive the action of the waves. Intertidal organisms protect themselves from being smashed against rocks or found washed up on beaches in many different ways.




Abalones secure themselves to rocks with their strong muscular feet.

Crabs hide under algae


Barnacles permanently attach themselves to rocks or shells


Periwinkle snails produce a glue to help them stay put


Mussels produce something called byssal threads that attach them to rocks.

The Animals and How They Survive

Animals of the Intertidal Zones



The intertidal zone is made up of four main zones, as you read before. Each zone consists of many animals, but in the high intertidal zone animals have to be able survive harsh environments. During high tide the high zone is exposed to rough waves, and the animals have to be able to adapt the changing of no water to rough water all the time. Many sea creatures have special features -like shells- that allow them to survive environments like these. Features like shells allow the sea creatures to be protected from waves by using the shell like a shield; it stops the waves from hitting the animal. Also, crabs are able to use their shells, not only for protection, but to store water. When it becomes dry or sunny where the crab is, it uses its stored water to hydrate it. Besides shells, there are protections like “Clinging”. Limpets cling to the side of rocks so that water and waves won’t push them away. Of course, animals that live in this area need a place to stay in, that they are able to go to when the waves are very high, and when there is little water. For many animals in this area tide pools and rocks are great places for this. Tide pools provide a safe environment for animals of the sea. It works just like a shell would work for a crab. It protects the water from hitting the sea creatures too hard. Here are some of the sea creatures that live in the high zone; Limpet, Striped, Acorn Barnacle, Dog winkle, Rockweed, and Sea Algae.



As you read before, there are four main zones of the intertidal zone. One of them is the "low intertidal zone". The low intertidal zone has many animals, such as: the key-hole limpid, sea stars, the two-spotted octopus, the nudibranch, the gumboat chitin, and the purple sea urchin. Many of these animals may be unfamiliar to you because they live in a part of the beach that is covered with water ninety percent of the time. Because they get sunshine only ten percent of the time, they have adaptations which allow them to stay underwater far longer than most animals in the intertidal zone. Their adaptions include things like being able to “breathe” underwater, which definitely helps them, after all, there are under water 90% of the time. Besides being able to stay under water for long periods of time, they also have adaptions like sharp teeth –which star fish have- that helps them scrape food from rocks, food like algae, while they are sticking on a rock!


The third zone is the middle intertidal zone. The middle intertidal zone is the most active zone of all four of the zones. Each day it has an equal amount of water vs. no water. Because 50% of the time it has no water, and 50% of the time it does, animals who live in this area (Like the anemones, barnacles, chitons, crabs, green algae, isopods, limpets, mussels, sea lettuce, sea palms, sea stars, snails, sponges, and whelks) have adapted to surviving in either lots of light, or all water. These creatures have adapted a few ways, but one of them is camouflage. Like animals in the other tide zones, these animals have used camouflage to hide from other sea creatures who think they would be a tasty snack! They have adapted by being able to stay under water for long periods of time. For example, anemones have been able to adapt by absorbing the water while it is there, and feeding on coomon food in the water-like algae. But, when it becomes sunny, the anemone is able to eat food -like mosquito larve- up out of the water. Animals have populated this area much more than the other zones not only because of the balance of water and light, but also because of what an equal amount of water and light does to that zone. What it does is it keeps the temperature less extreme. This means that it is never really super hot or super cold in the middle zone. Another characteristic that makes this zone great for the animals is that the waves are never huge, unlike the high and splash zones. But, although these are terrific living conditions for the animals listed before, larger animals find this area to not fit their living conditions. And last, the sea creatures that DO live in this area tend to feed on tiny particles floating in the water from the tides.


The last intertidal zone is the Spray zone. The Spray zone is the driest of all the zones, and the most “Beach Like”. The spray zone is not one of the most major ones (Like the low, middle, and high tide zones) but it is still an important part of the intertidal area. Along with all the other zones, the spray zone has a large amount of sea creatures. These creatures, like barnacles, isopods, lichens, lice, limpets, periwinkle snails, and whelks. All of these creatures are able to stay in the sun for most of their time, because in the spray zone, thats what it mostly is, sun. But, at high tide the spray/splash zone will be submerged in salt water. Sea creatures are able to stay in this sunny area because they have adapted to the land, and able to feed off things like particles in the sand.

By Theresa

Animals of the Intertidal Zone

There are many different creatures in the intertidal zone. Listed below are just some of the many creatures that live in the Intertidal Zone.
In the Spray Zone...barnacles, isopods, lichens, lice, limpets, periwinkle snails, and whelks.
In the High Tide Zone...anemones, barnacles, brittle stars, chitons, crabs, isopods, limpets, mussels, sea stars, snails, and whelks.

In the Middle Tide Zone... anemones, barnacles, chitons, crabs, isopods, limpets, mussels, snails, sponges, and whelks.

In the Low Tide Zone...anemones, chitons, crabs, isopods, sculpin, sea cucmber, sea urchins, sea stars, tube worms, and whelks.

The 4 Zones of the Intertidal Zone

The Intertidal zone is split vertically into 4 different zones within. They are, the spray zone, the high tide zone, the middle tide zone, and the low tide zone.
The Splash/Spray Zone:This is also called the Upper Littoral Zone. This area of the Intertidal zone stays dry most of the day, but it is sprayed with salt water during high tide. The only time it is flooded is when there is storms or extremely high tides.

The High Tide Zone:This zone is also called the Upper Mid-littoral. This section is only fully flooded in high tide.

Middle Tide Zone:This zone is also called the Lower Mid-littoral Zone. This zone is only flooded about twice a day with salt water from the tides.

Low Tide Zone:This zone is also called the Lower Littoral Zone. This area is mostly underwater,unless the tide is unusually low, then it gets exposed to air.