The water that covers 71% of our Earth is absolutely swarming with life. In 2010 the worldwide Census of Marine Life was released, the conclusion of a decade of research into what lived, lives, and will live in our seas and oceans. This research led to the identification of over 1,200 new species and the surveyors collaborated with the Encyclopaedia of Life and other scientific volumes. There are now 250,000 marine species that have been formally described, and it’s estimated that at least 750,000 more species remain to be described. It is now also estimated that there are more than a billion types of microbe (tiny organisms) that may live in the ocean. This essentially means that the ocean is literally teeming with creatures, from majestic Blue Whales to miniscule, invisible creatures, which all have their own special parts to play in keeping their home healthy. Unfortunately the census also revealed the extent of the damage that has been done to the waters since human history began. In this first half of a two-part piece on ocean life I’m going to tell you about what we as humans are doing to the sea water, what it means, and what we can do to prevent and even reverse the harm that has been done.
Pollution has become a much more important issue to all of us over the last few years with councils providing us with recycling bins, supermarkets reducing their packaging and rewarding eco-conscious shoppers for reusing plastic bags, and most households doing their bit to reduce the amount of waste that goes to landfill. Sadly, less scrupulous people and industries are still using the seas as a massive dumping ground for waste with plastics being the worst offenders; while wood and natural fibres will usually biodegrade over time in the salty seas, plastics can remain intact for untold years without reacting with the water. Divers have reported seeing polythene shopping bags at the deepest visited parts of the ocean and in 2013 a young Sperm Whale was found washed up on a beach in Spain with 37 pounds of plastic in its digestive system. Most of this was plastic sheeting used in the country to make greenhouses, but other items included rope, hosepipe, flower pots, a plastic spray bottle and, you guessed it, plastic bags. The unsuspecting marine giant had consumed 59 different plastic items in total. It’s also not uncommon to find penguins with their bodies stuck in rubbish and dolphins injured by trash. It’s heartbreaking that animals are suffering from something that is actually preventable.
While plastic doesn’t chemically break down in the seawater it does get broken up by sand and rocks. There are also many uses for small plastics, for instance in exfoliating face and body washes that contain little “beads” of plastic that are washed down the drain. That means that, as well as the obvious litter that industries and beachgoers have been throwing in the sea, there are now so-called “microplastics” (tiny fragments of plastic that range in size from sand-like to only being visible under a microscope). A recent study found that our oceans are heaving with these microplastics and, unsurprisingly, they aren’t doing the inhabitants any good at all. The investigation showed that, in areas where there are a lot of microplastics, up to 80% of marine populations can have them in their systems, having ingested them or got them trapped in their shells or gills. It’s also bad for the quality of the water as these plastics often contain or carry toxic chemicals like pesticides.
The world’s coastline is around 350,016 kilometres, about the distance from Earth to the moon. The Marine Conservation Society did a survey which found that there is an average of 2,309 pieces of litter per kilometre of coastline. That equates to about 808 million pieces of litter across the planet’s beaches. The only way to prevent this is to overhaul our approach to waste and re-educate ourselves. When it comes down to it plastic simply isn’t as disposable as we’d like to think. As well as investing in re-useable shopping bags it might be helpful to consider using glass bottles where available (getting milk delivered in reusable bottles), using recyclable plastics as far as possible and making sure you put as little plastic in your general rubbish as you can. If you’re worried about microplastics then choose your skin products with care to minimise the non-degradable waste you rinse away. Consider a sugar or salt-based scrub that will dissolve in the water, or an oat scrub that is more organic. And, very importantly, don’t litter!
Another problem caused by industries is chemical waste. Raw sewage is full of bacteria and viruses which can seriously harm humans who swim in it, let alone the fish and molluscs who live and grow in the contaminated water. People have been made ill by eating shellfish that grew in water near sewage outlets as they keep toxins in their tissue. As well as sewage, run-off of fertiliser and nutrients from farming enters the waterways and all of this matter feeds a kind of organism called phytoplankton. They breed very quickly and use up oxygen and, when they die, sink to the bottom of the water and rot, using up oxygen again. This means that the plants at the bottom of the riverbed can’t survive and the fish and other creatures that live in the waterways have neither oxygen nor food supplies. This leads to something called a “Dead Zone”: a place where living things are unable to thrive. There are “Dead Zones” all over the world and very little is currently being done to reverse the situation. While scientists are on the case industrial farming is playing a huge hand in the development of dead zones as the human population continues to grow. Growing your own fruit and vegetables and buying produce from local farmers is one way to reduce your own impact on the waters.
Industrialisation isn’t just responsible for adding chemicals directly to the water. The sea has always had a certain amount of carbon dioxide dissolved in it, but with rising CO2 levels in our atmosphere (widely believed to be caused by increasing use of fossil fuels) the level in the sea has gone up as well. This reacts with the water to make an acid which, in turn, is making the ocean as a whole more acidic. This is known as Ocean Acidification. While this does reduce the impact of CO2 on the atmosphere it has been predicted that there will be consequences for the aquatic life, particularly oysters, mussels and other molluscs that grow calcium-based shells, as these would dissolve if the water became too acidic. It is also said to cause coral to bleach and to affect the metabolisms of squid. It also seriously affects plankton. What’s most worrying about that is the fact that plankton forms the base of every food chain in the ocean. In short: no plankton, no fish. Climate change is a huge issue for every living thing on the planet, including humans. Reducing our carbon footprint is vital in restoring our planet’s balance. It’s been predicted that, ultimately, all that may survive in the seas are creatures that thrive in more acidic water, like jellyfish. Ocean Acidification has been shown to have happened before, millions of years ago; the sea bed shows layers where shellfish were completely dissolved by the acid in the sea. It took 100,000 years for the oceans to recover.
There is, of course, one very highly-publicised way that industrialisation and the demand for fuel has had a devastating impact on the seas: oil spills. In 2010 an oil rig called Deepwater Horizon was the cause of the largest oil spill in the history of the petroleum industry, so large in fact that is was visible from space. 780,000 cubic metres were spilled and, despite four years having now passed since the spill, the evidence is still washing up on beaches in the form of tar balls, leaving deposits on the sea floor and poisoning sea life with toxic chemical residues. In Australia there is a foundation that provides oil-covered penguins with jumpers to prevent them from preening (grooming their feathers) and accidentally ingesting the oil, as it is poisonous in large amounts. Despite clean-up attempts the effects of oil spills can be seen for years after the event.
So what does all of this mean? Our oceans are being very seriously affected by human behaviours. The good news is that these behaviours can change. All over the world “Hope Spots” are being set up to provide sanctuaries for marine life, where dumping and fishing are prohibited. These Hope Spots are already flourishing and have even been shown to be carbon sinks, meaning that they reduce carbon dioxide instead of creating it. Domestically, with less consumption of fossil fuels, a revised way of approaching waste disposal and a more eco-conscious attitude, we can all help heal the ocean and, maybe, even reverse the damage.