《Ocean Geographic》:Facebook & IG
Killing Ourselves Quickly…
Our ocean is the Earth’s life-support system. It provides food, oxygen, shapes our coastal environments, regulate our atmosphere and climate. Through the ages, mankind has relied on the ocean and its seemingly immense resources with little concern for conservation. However, in the last 100 years, our population grown from 1.8 billion in 1914 to 7.21 billion (ANU); coupled with industrial development, the use of fossil fuel and a consumerism economy, we have placed immeasurable stress on our world’s ocean. The ocean is getting warmer faster than predicted, creating havoc to the world’s climate.
Our ocean sustains all life on earth and yet we continue to neglect it, harming innumerable marine life, and polluting one of our most important resources. In the battle for preservation of our environment, the health of our oceans should be number one priority. Here, we would like to shed some light on the plight of our ocean, and how we are killing ourselves rapidly in the process.
Ocean acidity has increased by 30% globally during the last 200 years. The changing acidity of our ocean threatens to throw off the delicate chemical balance upon which marine life depend for survival. The basic science behind acidification is that the ocean absorbs carbon dioxide through natural processes, but at the rate at which we are pumping it into the atmosphere through burning fossil fuels, the ocean’s pH balance is dropping to a point where life within the ocean is having trouble coping. Increased acidity in the ocean would lead to a shortage of carbonate, a key building block some animals (and plants) need to build their shells and skeletons; these animals include shellfish like clams, oysters, crabs, lobsters and corals. Corals are the framework builders of reefs, by far the most diverse ecosystem in our ocean. The effects of acidification will not stop with coral reefs; corals are simply the first piece in a domino effect with sweeping impact that will be felt throughout the ocean.
We are vacuuming all life out of the ocean as thought resources are infinite. In truth, we are already scratching the bottom of the barrel. Many marine scientists consider overfishing to be the worst impact humans are causing on the oceans. The Food and Agriculture Organization estimates that over 70% of the world’s fish species are either exploited or depleted. By capturing fish faster than they can reproduce, we are disrupting entire ecosystems that interact with those species, from the food they eat to the predators that eat them. These losses make the ecosystems even more vulnerable to other disturbances, such as pollution. A complete overhaul of fishing policies, requiring global cooperation, is needed to achieve a sustainable system.
Irresponsible Fish Farming
Aquaculture, or fish farming, is the growing response to rapidly depleting fish stock in ocean. While it sounds like a good idea, it unfortunately has many negative consequences due to poorly managed operations. The main problem with aquaculture is efficiency: 5 to 20 fish are needed as feed to produce one fish. Nutrient and chemical pollution can occur easily in open-ocean operations when fish feed, excrement and medication are released into the environment. Farmed fish may accidentally be released into the wild, with destructive effects such as loss of native stocks, disease transmission, and damaging changes in habitat. Unfortunately, the biggest hindrance to overcoming the challenges of an industry that supplies nearly 50% of the world’s fish food supply is that it currently remains relatively unregulated.
Ghost fishing is an environmentally harmful issue, caused when discarded fishing nets or lines continue to catch fish and other marine life. Often, the traps trigger a chain-reaction when larger predators come to eat the smaller ones that have been ensnared, only to get themselves entangled in the mess. The issue of ghost fishing is most common with passive gear that has been abandoned, especially with the long liners.
Loss of Sentinel Species
Decimation of the ocean’s most important predators has significant consequences that ripple down the food chain. 50 to 100 million sharks are killed each year, either as bycatch from fishing vessels or directly hunted for their dorsal fins, used in an expensive soup popular across Asia. When finned, the sharks are thrown back into the water, often still alive and left to bleed to death. Unfortunately, sharks reproduce fairly slowly and do not have a large number of offspring, so these actions have long-lasting repercussions on the delicate ecosystems they help regulate. Despite the 1986 moratorium on many types of whaling, it still continues to be a problem, with some nations like Japan looking for loopholes and lobbying for lax regulations.
Loss of Coral Reefs
Keeping the coral reefs healthy is another major issue right now. A focus on how to protect the coral reefs is important, considering coral reefs support a huge amount of small sea life, which in turn supports both larger sea life and us, not only for immediate food needs but also economically. Global warming is the primary cause of coral bleaching, but there are other causes as well. Science is working on ways, but it also is a matter of setting aside marine conservation areas. Figuring out ways to protect this “life support system” is a must for the overall health of our ocean.
Offshore drilling continues to be a debate, but it is clear that greater oil production would only exacerbate the dilemmas of our oceans. The use of fossil fuels is the reason our oceans have been heating up and becoming more acidic, but offshore drilling takes the risks even further. When oil is extracted from the ocean floor, other chemicals like mercury, arsenic, and lead come up with it. In addition, the seismic waves used to find oil harm aquatic mammals and disorient whales. In 2008, 100 whales had beached themselves as a result of ExxonMobil exploring for oil with these techniques. Furthermore, the infrastructure transporting oil often erodes the coastline, creating more problems.
Scientists report that mercury levels in our ocean have risen over 30% in the last 20 years, and will continue increase another 50% in the next few decades. Emissions from coal power plants are the primary culprit, dispensing poisonous mercury that works its way up the food chain, eventually coming to us through the fish we eat. This neurotoxin affects the development of the brain in foetuses and has been linked to learning disabilities.
Dead zones are areas of the sea floor with little or no dissolved oxygen. These areas are often found at the mouths of large rivers, and are caused primarily by fertilizers carried in runoff. This lack of oxygen kills many creatures and destroys entire habitats. At our current rate, dead zones will increase by 50% before the end of this century.
The oceans are among our biggest resource for life on earth, but it is also our biggest dumping ground. It is astounding how much of our trash finds its way into the ocean. Animals become entangled and trapped in our garbage, delicate sea life like coral and sponges are destroyed, sea turtles and dolphins often choke on plastic bags (mistaking them for jellyfish or squid) or plastic bits clog up the digestive system of birds and other marine mammals causing them to starve to death. If that is not bad enough, hopefully the bigger-than-Texas trash vortex in the Pacific Ocean and its smaller cousin in the Atlantic will help serve as a wakeup call.
The dinosaurs did not see the meteors coming. What is our excuse? Continue the way we live, we are truly on the course of extinction.