Presentation on theme: "Lauren Burns November 28 th, 2011 Earth Science. Bathyal Zone The Bathyal Zone is also known as the twilight zone, so called because of the lack of light."— Presentation transcript:
Bathyal Zone The Bathyal Zone is also known as the twilight zone, so called because of the lack of light. The scarcity of light does not allow any plants to grow in this part of the ocean. It is for this reason that no deep sea creatures are plant eaters. The creatures that live here usually have weak muscles and soft, slimy bodies. When a fish is brought up from this zone or any of the deeper zones, they will puff up because of the change in pressure. This zone is the home of brittle stars, hatchet fish, and prawns.
Brittle Stars Brittle Stars are also called serpent stars. They live up to their name and break away very easily when under attack.
Hatchet Fish Hatchet Fish are probably some of the ocean’s strangest looking fish. They are usually 2.5 – 6 inches in length.
Prawns Prawns are almost the same animal as shrimp and the two terms are often used synonymously. The difference is that they come from separate sub orders which means their body structures are different. Prawns have plate like gill structures, longer legs and a longer pair of second pincers. Shrimp have branching gills, shorter legs, and a longer pair of first pincers.
The Abyssal Zone Absolutely no light penetrates the water to the abyssal zone. It is approximately 16,500 – 19, 500 ft. below the surface of the water. The many of the creatures here have under slung jaws and large eyes. The black swallower and the giant squid are two interesting species that live in the abyssal zone.
The Black Swallower The black swallower is a small fish sometimes called the chiasmodon. The black swallower has no scales and is 10 inches or less in length. Its body is long and slender with a super expandable stomach and a jaw like a snake’s which enables it to swallow food much larger than itself. Bony fish are its prey.
Giant Squid The most well known deep sea creature is most likely the Giant squid. This great animal’s stomach is above its head and it is 40 – 60 ft. in length. This amazing creature has made itself famous in adventure stories such as Moby Dick and others. In many fishermen’s tales, the squid has played the role of the “sea monster.” Giant squid are the prey of toothed whales.
The Hadal Zone The Hadal zone is the deepest zone of all. The depth exceeds 20,000 ft. There is no light in this zone, but oddly enough the animals have eyes which are always large. Viperfish and giant tube worms are two conspicuous species that live in this zone.
Viperfish Viperfish catch their prey with a special bioluminescent organ at the end of their dorsal spine. It is a glowing orb that they jiggle around to attract prey and make communications with other viperfish. They live about 30 – 40 years.
Giant Tube Worms Giant Tube worms live in the Pacific around geothermal vents. The geothermal vents make the surrounding water extremely hot. Even though it seems impossible for anything to live around these vents, scientists have found many living organisms that feed on bacteria. The bacteria, in turn, receive their energy from chemicals in the water through a process called “chemosynthesis.”
Giant Tube Worms cont. Giant tube worms have no mouth and no stomach, but they do have bacteria inside them that produce their energy. When giant tube worms hatch, they have a temporary gut and mouth. This allows the bacteria to enter their bodies. When the bacteria die, the tube worm also dies. These worms are eight feet in length.
Food Chain The base of the food chain is the tiny organisms called autotrophs(phytoplankton, zoo plankton, bacteria). There are more autotrophs than any other living things. The autotrophs are eaten by the primary consumers, also called herbivores. The herbivores, in turn, are eaten by the secondary consumers, which are carnivores, and omnivores. After the secondary consumers eat the primary consumers, they are eaten by the tertiary consumers, which are eaten by the quaternary consumers. There are also two other classes, the detrivores and the decomposers. The detrivores are the scavengers and the decomposers are bacteria and fungi, which eat away whatever the detrivores left behind. Most of the deep sea animals belong to the tertiary or quaternary consumers.