Due to its constant darkness, this zone is also called the midnight zone. The only light at this depth and lower comes from the bioluminescence of the animals themselves. The temperature in the bathypelagic zone, unlike that of the mesopelagic zone, is constant. The pressure in the bathypelagic zone is extreme and at depths of 13, feet 4, meters , reaches over pounds per square inch! Yet, sperm whales can dive down to this level in search of food.
The Abyssopelagic Zone or abyssal zone extends from 13, feet 4, meters to 19, feet 6, meters. It is the pitch-black bottom layer of the ocean. The name abyss comes from a Greek word meaning "no bottom" because they thought the ocean was bottomless.
Three-quarters of the area of the deep-ocean floor lies in this zone. The water temperature is constantly near freezing and only a few creatures can be found at these crushing depths. Here the only visible light is that produced by the creatures themselves. The water pressure at this depth is immense, reaching 5, pounds per square inch. In spite of the pressure, a surprisingly large number of creatures can be found here.
Sperm whales can dive down to this level in search of food. Most of the animals that live at these depths are black or red in color due to the lack of light. Abyssopelagic Zone - The next layer is called the abyssopelagic zone, also known as the abyssal zone or simply as the abyss. It extends from 4, meters 13, feet to 6, meters 19, feet.
The name comes from a Greek word meaning "no bottom". The water temperature is near freezing, and there is no light at all. Very few creatures can be found at these crushing depths.
Most of these are invertebrates such as basket stars and tiny squids. The aphotic zone makes up the majority of the ocean, but has a relatively small amount of its life, both in diversity of type and in numbers.
The seabed is also divided into the zones described above, but the ocean itself is also divided horizontally by distance from the shore. Nearest to the shore lies the intertidal zone , the region between the high and low tidal marks.
This hallmark of the intertidal is change, where water is in constant motions from ocean waves, tides, and currents. The land is sometimes under water and sometimes is exposed.
The neritic zone is from low tide mark and slopes gradually downward to the edge of the seaward side of the continental shelf. The organisms that live in this zone are bioluminescent; that is to say they produce and emit their own light. Examples of these creatures include certain types of plankton, jellyfish, squid, and the nightmarish barbeled dragonfish. The deep ocean is further divided into 3 zones: Midnight zone , the Abyss and the Trenches.
The midnight zone is also known as the bathypelagic zone makes up the first third of the deep ocean in the three layers model. It extends downward from 1, meters to 4,—roughly the average depth of the global ocean.
The temperature rarely changes, remaining at a fairly consistent 39 degrees Fahrenheit. As mentioned earlier, the only light in this regions does not come from the sun, but from bioluminescent animals who use their ability to hunt or find a mate. Some go for days living in complete darkness. However, there are a few sea creatures who swim this far down to feed, such as sperm whales. The abyss abyssopelagic zone is the middle layer of the deep ocean. It extends from 4, meters down to 6,, which for some global regions marks the seafloor.
The water temperature never rises above near freezing.
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