Exploring the Ocean Depths
Some animals that make up this zone include dolphins, blue whales, jellyfish, sea turtles, and more. Sharks in this zone range from 7 inches to 50 feet in length with streamlined bodies, which helps them move easily through water. Angelfish and Oysters can also be found here. Angelfish live in warm-watered reefs and there are around 70 different species. Some of the largest Oysters are 3 feet long, but can be as tiny as a couple inches long; another fact people may not know is that oysters start as males and turn into females.
Due to varying sunlight in this area, water temperatures range anywhere from 27-207oF. This zone is the only zone with enough sunlight to allow photosynthesis, which in turn means it is the only zone with plants. Plants that inhabit this zone are seaweed, algae, phytoplanktons, seagrass, and etc. Phytoplanktons are actually microscopic marine algae that are bouyant and float in the upper ocean.
Animal species living in the Twilight Zone include squid, crab, chain catshark, swordfish, wolf eels, gastropods, krill, and more. The viperfish has such a large mouth that its teeth don’t all fit; their jaws are hinged, they use bioluminescence, and are usually 11-12 inches in length. Also living here are eels, which are a boney, snake-like fish which migrate to breed and eat. The last fish mentioned in this zone is the cuttle fish. They have eight arms, soft bodies, and two tentacles, and they only live for about 1.5 years. In addition, they can change their skin color and pattern and will occasionally eat other cuttle fish.
The twilight zone can also be referred to as the midwater zone. This area of the ocean does not receive much light at all, so during the daytime, there is only enough faint light to see. Many creatures living in this zone have bioluminescence, which is a particular chemical combination that creates light to help animals see. Since there is an extremely small amount of light that reaches this zone, photosynthesis is not possible, which in turn means there are no plants in this zone. Animals in this zone are forced to eat food filtered down from above.
Entering into the Midnight zone, animals you would see include squid, sea stars, octopus, frill shark, large whales, and more. Some other animals that would be categorized as Bathypelagic Organisms in this area include deep-sea angler fish, slickheads, bristlemouths, gulper eels, other types of angle fish, and etc. These particular set of sea creatures usually have large mouths, long jaws, and lots of teeth to help them swallow any prey that may come their way. Interesting enough, male angler fish mate with females by biting into them, never letting go, and degenerating until they are only a sack of testicles.
Not surprising is that this zone has no plants or sunlight. In addition, this zone lacks in nutrients, which is why the fish in this zone have a low metabolism rate. The only source of light here is the bioluminescence given off by the organisms. Only about 5% of the food from the Sunlight zone reaches this ocean depth. Most of the organisms in this dark zone tend to be black, red, or transparent making them almost entirely invisible in the darkness.
A variety of animals lurk in the Abyssal zone such as deep-water squids, seapigs, basket stars, sea spiders, medusas, mollusks, and many more. Due to frigid temperatures and lack of nutrients the creatures in this area have extremely slow metabolism rates. A lot of these organisms only eat occasionally and some go months before their next meal. Most of them are small, however, they have flexible stomachs and big mouths because it may be a while before any more food comes along.
Abyssopelagic in Greek means bottomless and rightfully so. 75% of the ocean floor lies in this zone. Every 33 feet deeper increases the water pressure by one atmosphere (approximately 14.7 pounds per square inch at sea level). Water temperatures are almost freezing at 2-3 degrees Celsius. In addition, this zone has a low amount of oxygen, food, and nutrients, but is the largest environment on Earth, covering 300,000,000 square kilometers (approximately 115,000,000 square miles), which is about 60 percent of the global surface and around 83 percent of the area of the oceans and seas.
Not too many creatures live in this treacherous depth, but there are some that do. There are ploychaete worms, brotulids, sea cucumbers, Formaminifera, pale white hadal snailfish, tube worms, and more. These deep ocean creatures have adapted to the freezing depths, are invertebrates, and some have no eyes. Before tube worms, scientists thought all organisms lived off the sun’s energy. However, to their surprise, tube worms go through a process called chemosynthesis, which converts chemicals from the Earth’s interior into nutrients for the worms.
Also known as the Trenches this zone consists of cavities in the ocean floor. The deepest trench in the world at 10,911 meters (36,797 feet) is the Mariana Trench off the cost of Japan. They are formed where oceanic plates go below the overriding plate during subduction. The water temperatures are just above freezing while the pressure is 8 tons per square inch. That is about the weight of 48 Boeing 747 Jets. With this insane pressure and just above freezing temperatures, it leaves many trenches still unexplored.
wnct.com
seasky.org
oceanworlds.wordpress.com
sciencing.com
britannica.com
