The Great Barrier Reef

 

                 One of the goals on my “bucket list” is to scuba dive or snorkel in the Great Barrier Reef.  So I’ve decided to do some research to help peak my interest.  The Great Barrier Reef is considered to be one of the seven wonders of the natural world and it is the only living thing that is visible from outer space. The Great Barrier Reef covers an area greater than that of the Great Wall of China, spanning over 1,800 miles almost parallel to the coast of Queensland, Australia.  The reef possesses the greatest array of coral in the entire ocean, more than 400 different species.  Not only is the Great Barrier Reef home to vast amounts of coral, it also is a domicile for dolphins, sponges, and over 1,500 species of tropical fish.  Divers will never tire of the endless opportunities to view tropical corals, fish, and other animals, including the 120 year old giant clams.

                Several factors threaten the livelihood of the Great Barrier Reef.  Elevated ocean temperatures resulting from climate change cause a bleaching effect on the coral systems.  The increasing in temperature causes the algae that live in the coral to be expelled exposing the corals’ limestone skeleton. The climate change can have massive ramifications for the corals’ ecosystem affecting all of its ecology.  Pollution is also another key threat to the reef. The declining water quality is caused by water runoff from farms that compromise the makeup of the ocean water. Overfishing, disrupting the fragile ecosystem, and shipping industries, also threaten the longevity of the Great Barrier Reef.

                The reef also has cultural and religious meaning to many tribes that live around it.  The Australian aborigines and the Torres Strait Islander people have been living in the area for thousands of years, making their livelihood and cultural traditions amongst the reef.  The reef is also a historical marker for many shipwrecks and pre-modern explorers.  In the last thirty to forty years, great strides have been made by the Australian government to create laws preserving and protecting the Great Barrier Reef. One source states that, “the Australian Parliament passed the Environment Protect and Biodiversity Conservation Act which improved the operation of national environmental law by providing guidance about regional biodiversity conservation priorities.”  This law has made significant progress in reducing pollution and shipping damages to the reef as well as protecting species that are already endangered.

                The Great Barrier Reef has always been a fascinating aspect of oceanography to me.  From the vast array of sea life to the less obvious living creatures like the coral and the sponges, the coral reef seems like a foreign world to someone who grew up in the central United States.  Even though I live thousands of miles aware from the reef, I see the value in oceanic conservation efforts and the need to preserve one the Earth’s most incredible natural beauties. Legislation and societal awareness could be very beneficial in keeping the reef intact, as already displayed by the Environment Protect and Biodiversity Conservation Act passed in 1999. Though I don’t live in Australia, have not ever been, and may not ever have the opportunity to go, I still appreciate the mysterious wonders of the reef and care strongly to see it taken care of for future generations to enjoy.

 Links to Resources:
 National Geographic Barrier Reef
greatbarrierreef.org
Wikipedia- Great Barrier Reef

Disney's Oceans

              For my third blog, I watched Disney’s Oceans.  It is a very well made documentary that tells much about the oceans and its inhabitants.  From the smallest parts, like the larvae of crustaceans, to the largest inhabitants, like the blue whale, oceans possess a vast array sea life, much of which we have yet to even discover. One fascinating scene of the film showed a pod of dolphins swimming at a rapid pace to chase and devour a school of sardines.  Then out of nowhere, “dive-bombing” birds got in the mix to get their fill of the sardines as well. And lastly a massive blue whale, trumped all of the participants to get his fill of the sardines before they were too dispersed for the remaining diners.  The blue whale is one of the largest animals in the history of the world.  Whales are magnificently fascinating creatures.  Humpback whales sleep upside down and can tread water while they sleep to maintain their position. Orca whales feed on young sea lions near the shores.  It’s amazing that they have the mental capacity to monitor the sea lions’ patterns and plan their attacks.

                Though the sun goes down, the creatures of the ocean do not sleep. Many of its inhabitants are more lively at night, in the dark disguise than they would be in the daylight.  Many of the crustaceans venture out at night. Crabs inhabit new homes, shrimp dig new hideouts, and moray eels look for their next meal.  One fascinating creature, a sea slug called a Spanish Dancer, seems much more radiant than any land slugs that we see. The smaller creatures at the lower ends of the food chain use the night time to change or move their homes and gather food for the next days. 

                Ocean creatures are well adapted to disguising.  The octopus can disguise itself and camouflage with its surroundings to capture its prey.  Garden eels blend in with the sand before striking their victims.  Though stone fish are not very fast or agile, they have superior camouflage capabilities like the octopus, and can look just like a stone (thus their name) and capture their unsuspecting victims.  The leafy sea dragon lives at the same depth and in the same area its entire life and is almost unnoticeable amongst the vegetation it inhabits. Each creature is uniquely designed with abilities to ensure its survival.

                Disney’s Oceans, is a wonderfully made movie.  The images they were able to capture are simply remarkable.  With modern-day technology, we are able to see the mysteries of the ocean like never before.  The movie also draws attention to the important issues of over fishing and the endangered animals that we need to fight to protect.  Many of the awesome creatures that are featured in the film are in jeopardy of extinction because of overly lenient fishing policies and pollution.  It raises the issues that if we don’t modify our behaviors now, many of these creatures won’t be around for our children to observe.  I think everyone should watch this film to gain an appreciation for the intricacy and delicacy of the oceans’ ecosystem.  After all, “human indifference is surely the oceans’ greatest threat.”

 

The Open Ocean

                 For my most recent blog assignment, I watched “Open Ocean” produced by The Blue Planet. I learned a lot of fascinating information about predatorial fish and organisms in the ocean and their habitats. The video first discussed the striped marlin, which can grow to three meters long and can find fish they feed on up to 100 meters deep.  Several marlins will prey on sardines and other small fish by rapidly scooping them in their mouths near the surface.  The Sei Whale, another inhabitant of the deep, can get up to 14 meters long and 20 tons in weight. The Sei Whale utilizes the “scooping method” much like the marlins, and can rapidly ingest 10-30 fish in one gulp.  These whales also have the unique ability to monitor what is going on at the surface, and can “pounce” on birds lingering too close to the surface.  The video demonstrates how between the marlins and the whales, almost an entire school of sardines can be totally annihilated from the ocean food chain. Within a few short days, waters that were previously teeming with life are wiped out and the hunters must move on in search of their next meal. 

             

                The Manta Ray, opposite from the marlins and whales, feed off of plankton.  They can be as long as 3 meters across from wing to wing.  Manta Rays may travel for days before finding adequate food sources.  Certain fish that emit their eggs into the water for fertilization, make an ideal meal for the Manta Rays.  The Manta Rays’ mouths are like giant filters that can sweep through the egg-ridden waters, scooping up their meal and processing out what is worth keeping. One of the more endangered egg-bearing fish to this food chain, is the Yellow Fin Tuna.  If the tuna’s eggs even survive, it takes up to two years for them to be fully formed into a fish.  In three years, the egg could be a 3 meter long tuna, however only about one in a million survives this long! Thus this low survival rate contributes to international value of the Yellow Fin and their rarity. Plankton, nutrients, and small baby fish, get caught in the ocean current boundaries and can travel vast distances from where they have originally been produced. Because of this distribution, random parts of the ocean may become extremely fertile for plankton-feeding fish who then gather for days or weeks feasting on the local fare. 

                                                                        

                The complexity of the ocean’s ecosystem and food chain fascinate me.  It is so strange to me that fish can be born near one continent and then transported through the current system to become a mature fish in a completely different location.  It was apparent to me through the video that every fish in the ocean, no matter how big or small, is a part of the food chain.  It seems like there is always another fish or organism a little bit bigger that is willing and able to devour those beneath it.  It is also interesting to me that all of the ocean processes continue on their own and have for thousands of years without human intervention. The ocean seems like such a vast, mysterious part of our globe that will forever give us cause for research and curiosity.

Video Information 

The Mariana Trench

             The Mariana Trench is a fascinating feature of the ocean.  It is the deepest portion of the entire ocean and it is located near Japan and Guam.  It was created by ocean-to-ocean subduction, which generally does cause the deepest trenches.  The deepest part of the Mariana Trench is the Challenger Deep, named after an exploratory vessel that discovered it.  Though scientists have learned much about the trench, it is still not possible to measure its exact depth with current technology. However, from what we do know and can measure, Mt. Everest could be flipped upside down and placed in the trench, and still be substantially submerged.

                The Mariana Trench contains a vast array of highly unique marine life due to its extreme circumstances.  The furthest depths of the trench are highly pressurized and extremely cold, but they also have hydrothermal vents caused by the separating tectonic plates.  These vents emit minerals and fluids that can reach up to 300 degrees F. Thus certain animals such as the Angler Fish, have adapted to the extreme pressure and temperature changes.  Many species of crabs and various invertebrates also inhabit the depths of the trench, many of which live to be hundreds of years old. These animals live off of chemicals emitted by the hydrothermal vents.  Since sunlight cannot reach the depths of the Mariana Trench, plants and animals use a system known as chemosythesis instead of photosynthesis. Other strange phenomena include giant clams, spider crabs, and tube worm colonies.  One site stated that the Mariana Trench has been proposed to be used for disposing of nuclear waste.  Because it is a subduction zone, eventually the waste would be folded deep into the earth’s mantle, but we don’t know what effects these chemicals could have on the ecosystems of the great deep.

                               

                I never knew about the Marina Trench prior to a couple weeks ago.  The trench completely fascinates me because it puts the size of earth into perspective. It’s hard for me to wrap my mind around just how deep and vast it is.  I am also thoroughly amazed about the sea life that is able to live down there. There are such odd animals and organisms that are adapted to extremely cold and extremely hot temperatures.  It seems odd that no surface dwellers could ever come close to inhabiting the trench and yet those organisms not only survive but they thrive and are a vital part of the ecosystem.  I think the main thing that interests me about the Mariana Trench, is that there is so much we don’t know and are not able to discover about it.  In a world full of modern technology and all modern conveniences, it amazes me that we are still not able to delve into the depths of the Challenger Deep. To date a submarine vessel developed in Japan has been able to sustain depths of 6,400 meters, but nothing has come close to touching the approximate 11,000 meter depth of the Challenger Deep.  I think it is very neat that there are still some mysteries left on our intricate earth that our technology hasn’t been able to touch. 

Article Links:

Exploring the deep ocean floor 

Mariana Trench