The world’s oceans are a place of serene beauty, teeming with life in some areas and masked with darkness in others, they manage to seem full and yet empty, beautiful, and yet feral. The oceans generate most of the oxygen we breathe, they help feed us, they regulate our climate, give us new and exciting potential medicines, and cover 71% of the earth in their vastness.
In truth we owe a lot to the oceans of the world, and that is why on the 8th of June every year, we celebrate World Oceans Day, to honor all that is great about the oceans and our appreciation of their continued involvement in our lives. However, the world’s oceans are in trouble. Pollution, overfishing, and global warming are threatening the lives of marine creatures globally and their habitats. We rely on the oceans for food and for our livelihood, so unless our attitude towards them changes, we could be looking at a very different world. In light of World Oceans Day, we hope to address the major challenges that our oceans are facing and what steps are being taken to replenish and restore the world’s oceans.
Put simply, overfishing is overexploitation of the world’s fish stocks, where they become depleted to extremely low levels, creating a ripple effect through entire marine ecosystems. Probably the most well known example of overfishing is the overfishing of sharks for fins used in fin soup. Sharks are captured, their fins cut off at sea and the shark put back into the water. Sharks cannot survive without their fins and so die shortly after. This is not only very wasteful as only the fin is taken, but has had a seemingly inexorable effect on marine life. It’s estimated that between 26 and 73 million sharks are killed annually, however in 2012, that number rose to 100 million, that’s 190 sharks a minute, and could lead to mass shark species extinction within the next few decades if rates continue to rise. Shark fins may seem like a strange product to be in demand, after all they’re tasteless, and have to be boiled in stock to obtain flavor, but it has long been a delicacy in China to eat shark fin soup. This is mainly an option only for the rich, as 1 pound of shark fin costs around $330. Sharks are apex predators, meaning they have few to no predators of their own, and their numbers largely affect the numbers of other marine life populations. Because of the huge decline in shark populations, populations at the lower end of the food chain such as species of rays have boomed, consequently causing populations of shellfish to plummet, causing many fisheries to close. For example, a fishery in North Carolina that had to close in 2004, after being successful for several decades.
Furthermore, overfishing generally is increasingly becoming a pressing issue; Science magazine commented that world fish stocks may run out by 2048. The United Nations of Food and Agriculture Organisation estimated that over 70% of the world’s fish stocks are either fully exploited or depleted. In only 55 years humans have wiped out over 90% of the worlds apex predators, such as sharks, king mackerel, swordfish and Bluefin tuna. Bycatch is also a problem stemming from overfishing, where fish that aren’t targeted also get killed and have to be thrown back into the ocean, dead. For example there are fewer than 100 Maui’s Dolphins left in New Zealand because of high entanglement rates in nets.
The Slavery Behind The Seafood You Eat
There are ports on the western coast of Thailand where Burmese workers are smuggled to, with the promise that they will be able to have a well paid job in a factory, but once they arrive, they discover they have been sold into slavery. This is a familiar story for many Burmese men smuggled over the border into Thailand, but Myint Thein gives his story; “When I realised what had happened, I told them I wanted to go back,” he says hurriedly. “But they wouldn’t let me go. When I tried to escape, they beat me and smashed all my teeth.” The workers on these trawlers caught fish such as tuna and squid, and even “trash fish” bycatch, which is later used to feed the prawns in Thailand’s multibillion dollar farmed prawn industry. The fruits of these men’s penniless labour has, in all likelihood, landed on your dinner plate at some point or another.
The pH of the oceans has been decreasing in recent years, causing them to become more acidic and less habitable to the life they support. This is because around 30-40% of the carbon dioxide released by humans, in one way or another, is then absorbed by the oceans. This has a whole host of negative effects from depressed immune response in some organisms such as blue mussels, to coral bleaching. The rate of ocean acidification is rising as the amount of CO2 we pump into the atmosphere is rising due to global warming.
Disappearing Coral Reefs
Coral reefs are fragile and very complex marine structures that are very easily affected by small changes in the oceans. It’s estimated that around 25% of coral reefs around the world have already disappeared and another 67% could be heading that way in coming years. Overfishing and generally destructive, and unsustainable fishing practices account for the biggest decline in coral reefs. For example island nations such as Samoa and The Philippines have seen a dramatic decrease in fish stock numbers which many of the local islanders rely on, so in response they started fishing using cyanide and dynamite fishing, which further degrades the coral systems. Global warming also has a huge affect on coral reefs, with bleaching either killing or at the very least weakening coral reefs.
The negative effect of mercury pollution to human health has been known for decades; in high enough doses it can cause damage to the brain, kidneys and lungs. Mercury is often a pollutant released from industrial emissions, and finds it’s way into the world’s oceans. Fish at the top of the food chain contain more mercury because they also store the mercury from the fish lower down on the food chain that they have consumed. These fish include some of our favorites such as tuna and swordfish. Because of the negative effects of mercury poisoning, pregnant women are discouraged from eating fish thought to be high in mercury, and young children are also discouraged from eating it due to the chance of delayed neurological development. Mercury levels are expected to rise in coming years mainly due to the coal-burning plants in India and China sending toxic fumes over the ocean, which are then released into the water through rainclouds.
Ocean Dead Zones
Ocean dead zones are areas of the ocean with little to no life because of extremely low oxygen levels. This is mainly due to pollution from humans and natural causes that result in the depletion of nutrients. There are 146 dead zones in the world’s oceans that are unable to support life. The size of these dead zones varies from as little as one square mile, to the largest one, which is 70,000 square miles of lifeless ocean. The main cause behind ocean dead zones is industrial pollutants in fertilizer used for farming. Phosphorus and nitrogen are the main pollutants at play here; when these elements get into the coastal waters, they over-fertilize the phytoplankton and algae, causing their populations to rocket an alarming rate. When these populations subsequently die, the process of decomposition depletes the oxygen supply leaving it then unsuitable to sustain life. With global meat consumption expected to rise by up to 50% within the next 25 years, agricultural industry is set to raise even higher, placing increasing pressure on coastal areas and contributing to the growing number of dead zones.
The most notorious effect oil has on the oceans, as we’re sure you’re all aware of, is oil spills. When oil coats the fur of certain mammals such as sea otters, it destroys their insulating ability, a similar thing also occurs with birds if their feathers are exposed to oil. Having this insulating ability destroyed means these creatures have little to no protection against water and the cold, and will frequently die of hypothermia. For the birds and mammals unfortunate enough to ingest the oil, it’s also poisonous to them, also leading to a painful death. Fish are not affected in the same way as birds and mammals; the effect on fish and shellfish is often delayed because it requires oil making it’s way into the water columns. The main consequences on fish exposed to oil are; reduced growth, unusual and enlarged livers, significant change in heart or respiration rate, and a drastically slows or disturbs reproduction. Hundreds of millions of gallons of oil end up in the oceans each year, and most of this alarmingly high figure doesn’t account for large oil spills, but small, regular dumping of oil. For example bilge cleaning of ships releases 137 million gallons of oil into the oceans, annually and this is only a small part of the problem.
Lastly on our list of problems is tourism and development. Coastal areas are characterized by high biodiversity; they contain some of the most rich and diverse ecosystems and habitats existing on this planet. Unfortunately for these ecosystems, coastal areas are a much-loved place by humans, whether that’s to live or to vacation to. Around 220 million tourists visit the Mediterranean annually, 100 million of which will visit the beaches. This number is said to rise to 350 million in less than 20 years. The infrastructure that is required to maintain these levels of tourism and the pressure it puts on local resources means some habitats are destroyed beyond repair. Around half of the Mediterranean’s coastline is now urbanized, and with the increasing pressure applied in coming years, the area of non-urbanized land will most likely shrink.
Detailing all the stressors for the world’s oceans would leave us with an almost unending report, so here we’ll summarize some of the other problems our oceans are facing. Rising temperatures are causing not only ocean acidification but also a plethora of other problems such as affecting ocean currents. Ocean currents are important in transporting nutrients necessary to support life into lower latitudes, these currents are slowing down due to global warming, we could see this having a massive ripple affect on the food chain in coming years. Another noticeable issue facing our oceans is the Great Pacific Garbage Patch. This is an area in the North Pacific Ocean with high concentrations of plastics, other synthetic materials, chemical sludge and various other kinds of debris that have been caught up in surface currents. Many of these chemical and synthetic materials are toxic to marine life and contribute to plummeting numbers.
What is Being Done?
If you’re not depressed by now, then I haven’t been doing my job properly! But on a serious note, what is being done about these issues? Could we be looking at a brighter, more sustainable future for the world’s oceans? World Oceans Day is helping tremendously to raise awareness for ocean issues; in 2013 around 600 events were held in 70 countries, and while the official numbers aren’t yet available for 2014, the number is thought to be even higher. Sadly not much is being done in terms of ocean conservation thus far, many coral reefs are becoming protected areas, and the list of possible protected areas continues to grow as they look to be officially protected. A number of shark species are now considered endangered and are being protected, and proposals for more aggressive management of fisheries and reducing bycatch could see rejuvenation in fish stocks. If this is something that concerns you greatly, there are small things you can do to make a small impact, however it may seem like a drop in the ocean. The small things you can do include; reducing your carbon footprint, recycling plastics, finding where your shellfish are sourced from to avoid ones caught by slavery.
There’s something blissfully ironic in the concept that the oceans that first brought life on this planet into existence, are threatened with death by one of it’s own creations, us. These problems our oceans face are similar in a sense to the way most problems created by humans seem to go; ignore the seriousness of the problem, carry on exploiting until it’s almost too late, then find a solution. The world’s oceans are already changing in a way where much of the damage may be irreversible at this point, but that doesn’t mean we shouldn’t try to conserve what we have and hopefully, over time, bring the oceans back to a more healthy state. Unfortunately, this is going to be a long road, it’s a very complex vortex of issues, with a lot of people involved at every step along the way and creating a conservation consensus across a range of disciplines will be a difficult task, but one that needs to be done. In an ideal world; humans will move to endorsing local small fisheries in greater numbers, rather than the huge commercial fishing companies, practices like line fishing that accumulate high amounts of bycatch will be banned, several areas of ocean will be protected, and even the unprotected areas will be protected from any human waste chemical runoffs from farming, and sharks will cease to be slaughtered in their millions for a tiny, tasteless part of their anatomy.