The ocean covers about 70% of Earth’s surface. It’s the home for up to 80% of all life on Earth. It is imperative to maintain the integrity of the ocean systems for the functioning of all the natural cycles and systems. It is the biggest carbon sink we have; marine life sequesters carbon when it sinks to the bottom of the ocean keeping the carbon in the atmosphere in check. Moreover, our oceans soak up heat and distribute it evenly throughout the planet.
Source: The Ocean Cleanup Plan
Human activities are damaging the aquatic ecosystem in numerous ways. Our waste, especially plastics is buoyant and resilient to the marine environment hence they don’t sink or dissolve, they are simply transported by converging currents and accumulate at The Great Pacific Garbage Patch which is located halfway between Hawaii and California. It is estimated to have over 150 million tons of waste and it has a surface area of 1.6 million square kilometers, an area three times the size of France. As plastic breaks down into smaller and smaller pieces known as microplastics, it is seeping into every living creature in the ocean hence it has become common to see animals washing up with their stomachs filled with plastic. Each of these creatures, help keep the entire ocean alive. For example, when dolphins and whales return to the surface to breathe, they fertilize tiny marine plants in the ocean called phytoplankton, which every year absorb four times the amount of carbon dioxide than the Amazon rainforest does, and generates up to 85% of the oxygen we breathe. So, protecting these animals means protecting the entire planet.
Source: NOAA Climate
Apart from waste, we are also putting carbon dioxide, from burning fossil fuels, into the oceans. As most of the CO2 in the atmosphere is absorbed by the ocean, the access CO2 turns into carbonic acid which dissolves the hard shells and exoskeletons on species such as Oysters and Corals. This leads to Coral bleaching. Corals are crucial as they are the trees of the ocean that regulate the ocean oxygen levels which helps the entire ecosystem breathe. The excess CO2 also increases the amount of heat trapped in the ocean, this increases the water temperature especially at the surface where most ocean dwellers, from plankton to fish to whales live. These animals face high risks from warmer temperatures such as increasing levels of mortalities, loss of breeding grounds, and mass movements as species search for favorable environmental conditions. Furthermore, warm water takes up more space than cool and with global warming melting ice glaciers, the sea levels are rising. Ocean warming, coupled with ocean acidification affects marine species and ecosystems and, consequently, the fundamental benefits humans derive from the ocean, threatening food security, increasing the prevalence of diseases, and causing more extreme weather events and the loss of coastal protection.
It is not just what we are putting in the ocean but also what we are taking from it. The mass scale of Commercial fishing leads to the catching of 2.7 trillion fish every year, that’s 5 million killed every minute! This has led to global fish populations plummeting to near extinction. Every seafood animal has a role in the aquatic food chain, if the volume of level 1 fish such as sharks reduces, the volume of its prey, the seals on level 2 will overpopulate and wipe out their food supply of the smaller fish, the salmons at level 3. Eventually causing level 2 to go extinct due to starvation. Hence the key to the survival of our oceans is to keep the population of each level to an optimum, which the oceans can do by themselves if only we left it alone. Overfishing and overfishing-related issues such as; bycatch, unethical fish farming, bottom trawling, and wastage are disrupting the ocean systems in irreversible ways.
The interconnectedness between all these problems is clear. The root of all these problems is clear, the humans. To help with the smooth functioning of the most important and interconnected system on earth one simply has to stop interfering! We need to understand our role as small living things on earth compared to the vast oceans.