EnviroWeekly | Overfishing only one of many threats to our oceans | The Triangle

EnviroWeekly | Overfishing only one of many threats to our oceans

Imagine you’re in your hometown hanging with your friends and family. The sky is blue, and the temperature is just right. Suddenly, you find yourself running for your life. An infinitely large and porous blanket is nipping at your heels and destroying everything: your house, plants, animals, your friends’ houses, your friends, and finally you can’t run any longer and are swallowed up as well. It’s not an alien invasion, but it’s still terrifying.

Now imagine the ocean: that vast tract of blue that occupies the majority of the planet’s surface, containing specks of green, white and brown. Every single day, many, not just one, of those large and porous blankets, called trawl nets, scrape the ocean floor, leaving destruction in their paths and claiming the lives of billions of marine life forms. Yet when looking at marine life depletion, there are many things other than trawl nets that contribute to the decrease of marine systems in the Earth’s oceans. I want to explain some causes and effects of marine life disruption, point to local outreach groups working in the area, and suggest solutions for Drexel affiliates.

One of the easiest ways of understanding detrimental behavior to the oceans is to look at pollution. With the coverage of BP’s Deepwater Horizon disaster in 2010, one could see that the devastation to the Gulf of Mexico was vivid. At the disaster’s peak, it necessitated the closure of commercial fishing activities over 88,000 square miles by the National Oceanic and Atmospheric Administration. According to the Federation of American Scientists, “coastal areas are especially vulnerable because oil can be stranded in wetlands and other coastal ecosystems after being washed in by waves and tides.”

In addition to mentioning that oil can coat and suffocate small animals and plants that live on shores, the FAS says that oil can remain on the Gulf floor, affecting corals and bottom-dwelling organisms. Oil left unattended in wetlands can cause long-term damage to growth, as these areas provide shelter to many organisms. It literally affects the entire food web as organisms dwell in the polluted areas, and it outweighs the devastation to individual fish species in the open ocean. The BP oil rig explosion is just one out of many examples. The Exxon Valdez disaster, Nigerian oil spills and the Gulf War oil spill have all added their share of oil to the oceans around the world.

Besides fossil fuel extrapolation and transportation pollution, waste and agricultural runoff have created dead zones in the Gulf and around the world. As I mentioned in an earlier op-ed, almost 173,000 miles of dead zones populate U.S. waterways due to agricultural runoff from intensive farm practices and factory-farmed sewage runoff. Because this type of pollution is ongoing with increased production in factory farms, thousands of dead fish wash up on shores every year.

Consider the effects of climate change and our warming planet. Some of us have heard of carbon sinks. The ocean acts as one, but it is losing its ability to absorb carbon every year, just as the Amazon is losing its ability to act as an effective carbon sink with more deforestation taking place. As the planet absorbs carbon less effectively (in addition to increased anthropogenic emissions) and produces less oxygen in the atmosphere, more carbon will remain in the atmosphere, causing heat absorption from the sun. As the planet increases in average temperature, the ice caps that help reflect sunlight and divert heat absorption will decrease in size and melt, not only accelerating the rate at which future ice will melt but also unbalancing the sodium levels and temperature in seawater. The cold and fresher water that was kept in ice for centuries will enter major currents like the North Atlantic Current. This will not only affect the marine life system (which is used to a warmer current as the current continues the Gulf Stream northeast) but also decrease the temperature of the current that provides moisture and warmth for Northern Europe.

Sea life will be affected particularly with warmer ocean temperatures in areas like Australia and the Great Barrier Reef. The collection of coral reef acts as a filter for ocean waste and as shelter to many different marine species. Factors like increased water temperature, reduced salinity, acidification, overfishing and sedimentation cause large-scale coral bleaching, which kills the reefs and thereby reduces the efficiency of the corals at filtering the ocean and providing a habitat and protection for marine life. Humans that rely on coral reef organisms for food and trade will be negatively affected if more coral reefs undergo bleaching events. Although it sounds like the ocean is heating up and cooling down simultaneously, the ocean is on average warming up. Despite this, the decrease and increase in ocean temperatures in different areas of the world causes various effects on marine ecosystems that will ultimately lead to rising temperatures.

Human waste contributes to marine life depletion as well. As of now, there are floating plastic islands in the five gyres of large ocean currents, with the plastic pollution in the North Pacific Gyre measuring to almost twice the size of the U.S. There are a few other gyres that have accumulated plastic waste, but the five gyres have the largest amounts of plastic whirlpooling and breaking into smaller particles, affecting marine life health and ultimately human health. Persistent organic pollutants, such as PCBs, DDT, pesticides and hydrocarbons, are absorbed by these plastic particles and build up enough that marine life will unknowingly consume them.

Going back to the fishing industry, we find increasingly more devastating practices used by the industry to capture and trade marine animals for consumption and consumer products. Tyler Kruszewski, representing Shark Angels and Fin Free Pennsylvania, also a biology major at Drexel in the cellular molecular genetics biochemistry concentration, spoke to the Drexel Sierra Club about the need for banning the sale of shark fins. Seventy-three million sharks are killed each year for their fins, the main ingredient in shark fin soup. Regional shark populations have already decreased by 95 percent, and the continued sale of shark fins will lead to even fewer populations. Sharks are necessary predators of the marine ecosystem, as they regulate the food web and control the fish populations’ effect on marine plant life and micro-organisms.

The fishing industry also uses environmentally destructive fishing techniques that not only decrease the levels of fish populations but also do not allow those populations to grow back to sustainable levels. As I mentioned earlier, the use of trawling nets results in large amounts of by-catch (fish species that are not intended to be sold) that die as a result of the inability to escape and thrashing against other fish as changes in pressure cause rapid decompression of the swim bladder. Little is known about the deepest depths of the ocean floor, and areas around the seamounts and vast sea forests contain estimates between 500,000 and 5,000,000 unknown species. Bottom trawlers are able to destroy these areas within our own lifetimes and leave these undiscovered species virtually unknown.

Gill netting, a less intensive fishing practice, also contributes to overfishing, leaving fish trapped for hours and days, causing some to die from lack of movement and predation. The economics of these techniques may stand to show profit in the short term, but the long-term effects of these standard fishing techniques will eventually bring economic collapse to the industry as fishermen have less fish to haul back in the coming decades.
I don’t think we’ll end up like Kevin Costner in “Waterworld,” but current trends certainly don’t deny the plausibility of that plot. So what can we do, particularly for marine ecosystems? One easy solution is to decrease the amount of plastic you use and buy, as that positively correlates to a decrease in plastic pollution. While not using plastic bottles and bags, you can either reuse old canvas bags and secondhand clothes, or you can buy from organic clothing and accessory companies. Brian Linton, founder of United By Blue, a Philadelphia-based apparel company that sells organic shirts and bags, spoke to the Sierra Club about its efforts to remove trash from U.S. waterways. For every item sold, UBB removes one pound of trash. Three years since their founding, they have removed over 140,000 pounds of trash, including 22,000 plastic bottles.

Another behavior to consider changing is fish consumption. The above data have shown that not only are wild caught fish subjected to cruel practices that destroy marine ecosystems, but intensively farmed fish (one solution in the eyes of the fishing industry) are equally concerning, environmentally speaking, with respect to poor diet, lack of welfare concern, economical waste, biological waste and lack of sustainability. It would be wise to reduce or even eliminate fish consumption, as these fish populations and other marine life need time to repopulate and recover. With current amounts of fish being caught (over a trillion fish per year), the consumption of fish is not environmentally sustainable.

Although there are many hazardous practices taking place at this moment, there is still some time to act. Fin Free Pennsylvania and Shark Angels are two great organizations to support, as they focus on one of the root problems in the fishing industry. You can decrease the amount of plastic you use and discard as well as volunteer or donate to organizations that are working to clean waterways. Most importantly, you can get more informed and inform others.

Benjamin Sylvester is a member of the Drexel Sierra Club. He can be contacted at [email protected]
The Drexel Sierra Club contributes weekly.