As the Earth’s life-sustaining body, the health of our ocean is vital to ensure the survival of not only our own species but countless others. Here are five facts which highlight the different kinds of stresses our seas face - and how you can get involved to protect these precious ecosystem
The 5 most common types of debris found in marine clean-ups are all single-use plastics.
According to the 2014 annual coastal clean-up, which involved 91 countries, 561,000 volunteers and over 22,000km of coastline, cigarette butts top the list (32%), followed by food wrappers (9%), plastic bottles and caps (6% and 8%) and drinking straws.
Of course, the afterlife of plastic is a huge problem that is just beginning to be understood around the world. Single-use plastics have even been known to be ingested by crustaceans living at the bottom of the Mariana trench - the deepest part of the Pacific Ocean. The good news is reusable alternatives exist, so wherever possible, you can avoid unnecessary single-use items simply by politely refusing them. Carrying your own long-lasting bottles, containers, cutlery, and straws is a great way to set an example to those around you, as well as supporting businesses who are also making changes to minimise their waste. On the inevitable occasion where you must use plastics, see if there are ways you can reuse or upcycle them before recycling or disposing of them responsibly and, of course, never litter.
2. Oceans are acidifying faster than they have in over 300 million years
This topic has been discussed for years but, even though it’s now “new” news, being able to absorb around 40% of all human emissions is enough reason to want to protect our oceans. Following the industrial revolution, our carbon emissions as a species have continued to rise and the ocean can’t absorb them all. This has led to the lowering in pH of our oceans and fewer carbonate ions available to form and strengthen the building blocks of organisms such as shells, corals and urchins. This decalcification can also affect the behaviours of other organisms, changing their ability to detect predators through auditory cues. Additionally, seafood is the largest traded food commodity in the world: billions of humans depend on it for sustenance and survival.
If you’re a diver or snorkeller, it’s important to make sure you’re being minimally invasive to marine life when in the water - you can learn more about good diver behaviour by checking out some of the materials provided by Green Fins (the initiative we run in partnership with UN Environment Programme), as well other actions you can take, such as avoiding wearing sunscreens containing chemicals such as oxybenzone, which studies have shown may harm coral reefs.
3. Ocean noise pollution in some areas has doubled every decade for the last 60 years, causing stress, disturbance and even death of marine life.
Although our oceans occupy 71% of the Earth’s surface area, today it can still be hard for animals to get some peace and quiet. Sound travels through water around 4 times faster than air, and anthropogenic noise pollution can weaken the immune systems of animals and even cause animals to flee and abandon their valuable habitats. Consequently, this can create unnatural shifts in the ecosystem. The biggest sources of ocean noise are from oil exploration, industrial shipping, and high-intensity sonar.
Not only do these huge vessels create noise, but they also can easily strike and kill larger marine animals and have been linked to the decline of species such as the North Atlantic right whale and the Florida manatee. If this is an issue you care about, you can read the latest reports and findings on the International Ocean Noise Coalition (IONC) website - a partnership of over 150 NGOs working to combat noise pollution in our oceans
4. Each year, over 1 million seabirds, 300,000 porpoises and dolphins, and 100,000 other marine mammals are killed by ocean pollution - often this is from entanglement from nets and ingestion of plastics.
© BBC / Blue Planet 2
With growing food demands, non-selective fishing methods are being used more often, resulting in the capture of sharks, tuna, as well as non-fish marine species, including sea turtles and birds. Bycatch is often discarded; however, by the time they’re put back in the ocean, the animals are often dying or already dead. Multiply this effect by the thousands of miles of fishing nets and hooks put in the oceans each day and the numbers are devastating. You can help by avoiding eating fish caught from methods which have a high bycatch - such as longline, trawling or gillnets. The Marine Conservation Society’s Good Fish Guide is a great starting place - but remember the decline of a species may vary all over the world, so it’s also a good idea to double-check things on a more local level.
5. There are over 500 ‘dead ocean zones’ across the world, covering an area equal to the United Kingdom.
A ‘dead zone’ is a hypoxic, or low-oxygen area in an ocean or large lake which is caused by excessive human pollution and other factors. It refers to a body of water being unable to sustain marine life at the bottom or near-bottom areas and becoming barren, like a desert. Very few, if any, species can survive in these conditions so this results in a worrying lack of biodiversity. When oxygen falls to 2 parts per million in an area of an ocean or lake, small, mobile organisms such as crustaceans, snails, and fish will try to move to a different habitat. This impacts everything higher up the food chain who will then struggle to find food. Organisms that cannot fully escape a dead zone, however, may face large-scale deaths.
A big proportion of this pollution comes from ‘runoff’ from oil as well as wide-scale pesticides, insecticides, and herbicides used on crops, which leach from farmland into rivers and inevitably, the ocean. To help dead zones to recover, it is important to find ways to manage the runoff of nutrient waste into watersheds. A simple switch you can make at home is to buy organic food if it is available to you or even try growing some vegetables at home. Be sure to dispose of all kinds of oil correctly: returning it to appropriate organisations in a sealed container rather than throwing it directly down a sink or in the garbage. Robert Diaz, of the Virginia Institute of Marine Science, College of William and Mary, and his colleague, Rutger Rosenberg of the Department of Marine Ecology at the University of Gothenburg have stated "there is no other variable of such ecological importance to coastal marine ecosystems that has changed so drastically over such a short time,’ and reducing our use of these harsh chemicals will ultimately lead to less overall damage to our oceans.
It can be easy for individuals to feel somewhat helpless in all of this. But it’s crucial to remember every positive action adds up. Making changes to our lifestyles is a leap for all of us. If something doesn’t seem achievable for you, don’t force yourself. Nobody is perfect, but if everybody tries to improve where they can, it’s a great step in the right direction. Finally, people can’t find solutions to a problem they’re unaware of. So spread the word!