According to National Geographic, pollution is defined as “the introduction of harmful contaminants that are outside the norm for a given ecosystem.” Until fairly recently, it was widely believed that due to the vastness of the oceans, any trash or other pollutants dumped into the ocean would have minimal impact on the overall health of the ocean – a sort of “dilution” policy. Today, it is painfully obvious (due to the approximately 400 ocean dead zones around the globe) that our current practices must change if we are to protect this vitally important ecosystem.
Ocean pollution takes many forms. At present, “garbage patches” have gained much attention. The Center for Biological Diversity states, “Not one square mile of surface ocean anywhere on Earth is free of plastic pollution.” Further, it has been suggested that by 2050, plastics in the ocean will outweigh all the fish in the sea. However, the concept of the Pacific Garbage Patch as a “large and continuous patch of easily visible marine debris items such as bottles and other litter – akin to a literal island of trash that should be visible with satellite or aerial photographs” is just not the case according to the National Oceanic and Atmospheric Association (NOAA). Yes, there are higher concentrations of litter in these areas, but much of the trash is “actually small pieces of floating plastic that are not immediately evident to the naked eye.” This is not to say that garbage patches should be disregarded; on the contrary. Even though the size of the litter may be small, the damage it can cause to the oceans and its inhabitants is great. Plastics and toxins ingested by marine wildlife can not only harm those creatures consuming them, but can make their way up the global food chain to bigger fish and eventually into humans consuming seafood.
While much attention has been given to the impact of plastics on the health of the oceans, one of the greatest causes of pollution is called nonpoint source pollution. A result of runoff, nonpoint source pollution comes from septic tanks, motor vehicles, farms and ranches, factories, top soil, sewage overflow, etc. by way of storm drains and sewers. For example, small amounts of oil from engines fall to the pavement and eventually make their way to the sea. The National Resources Defense Council (NRDC) estimates that 80% of marine pollutants originate from land-based sources, some that are far inland. NOAA states that “waterborne infectious diseases, harmful algal bloom toxins, contaminated seafood, and chemical pollutants” are all signs that not only is the health of the ocean threatened, but so too is the health of the general public and our coastal economies.
Noise pollution also permeates our ocean. Noise from commercial tanker and container ships along with sonar emissions can carry for miles in large bodies of water. Even earthquakes can cause noise pollution. The NRDC states that “in the hunt for offshore oil and gas, ships equipped with high-powered air guns fire compressed air into the water every 10 to 12 seconds for weeks to months on end.” So what impact do these pollutants have? Many marine species, particularly aquatic mammals, rely on sound for everything from finding food to finding a mate, from navigation to migration to communication. When those sound patterns are interrupted the effects can be disastrous: some species leave their habitats, having devastating effects on coastal economies; some sounds themselves can actually injure or kill marine species.
Organizations around the globe are doing their level best to come up with ways both big and small to protect the health of our oceans. A joint program between UN Environment and the Reef-World Foundation called Green Fins works with diving businesses and governments to not only reduce the impact of diving on ocean ecosystems, but to reduce their environmental impact by dealing with their waste responsibly and by participating in underwater or beach clean ups. NOAA’s Marine Mammal Health and Stranding Response Program conducts health assessments on dolphins in coastal waters and then tracks their movements to help identify sources of contamination.