Marine Conservation - Oceans Under Siege

Keeping the oceans clean

Oceans Under Siege

Our ocean is under siege. From everyday trash like plastic bags, food wrappers and drink bottles, to larger items like car batteries, kitchen appliances and fishing nets, our debris is entering the sea at an alarming rate.

Our Ocean has become a Dumping Ground

Marine debris is not only unsightly, it’s dangerous to sea life, hazardous to human health and costly to our economies. Marine animals can become entangled in debris or mistake small particles of trash for food – often with fatal results.

Divers, swimmers and beachgoers can be directly harmed by encounters with debris or its toxins. And, the costs of plastic debris to marine ecosystems are estimated at $13 Billion Dollars a year..!!

We Need to Act Now!

The world needs to “act now to avoid living in a sea of plastic by mid-century” stresses a publication by the UN Environment Programme (UNEP) and GRID-Arendal. The report, “Marine Litter Vital Graphics” which summarizes current knowledge on plastic litter in the oceans and highlights areas where more research is needed, predicts 33 billion tonnes of plastic will accumulate around the planet by 2050 if current trends continue.

Although the impact of marine litter on large marine creatures like turtles, whales, seals and seabirds is relatively well documented, the report stresses that it is “only part of the problem.” It explains that organisms at every level can be affected by plastic. The report discusses challenges related to plastics as a source of toxic chemicals in marine organisms as well as the impacts of plastics on human health.

Observing that plastics have only been mass-produced for approximately 60 years, the report states that it is not possible to know how long they will last in the marine environment, stressing that most plastics are extremely durable and not biodegradable. Rather than eliminating plastic, the report suggests the goal should be to use plastic more efficiently and in an environmentally sustainable way.

For instance, the report states that the proportion of plastic that is recycled may not even reach 5% of production.

Failure  The Solution to Pollution is Dilution!

The oceans are so vast and deep that until fairly recently, it was widely assumed that no matter how much trash and chemicals humans dumped into them, the effects would be negligible. Proponents of dumping in the oceans even had a catchphrase: “The solution to pollution is dilution.”

Today, we need look no further than the New Jersey-size dead zone that forms each summer in the Mississippi River Delta, or the thousand-mile-wide swath of decomposing plastic in the northern Pacific Ocean to see that this “dilution” policy has helped place a once flourishing ocean ecosystem on the brink of collapse. There is evidence that the oceans have suffered at the hands of mankind for millennia, as far back as Roman times.

But recent studies show that degradation, particularly of shoreline areas, has accelerated dramatically in the past three centuries as industrial discharge and runoff from farms and coastal cities has increased.

Pollution – A Brief Overview

Pollution is the introduction of harmful contaminants that are outside the norm for a given ecosystem. Common man-made pollutants that reach the ocean include pesticides, herbicides, chemical fertilizers, detergents, oil, sewage, plastics, and other solids. Many of these pollutants collect at the ocean’s depths, where they are consumed by small marine organisms and introduced into the global food chain. Scientists are even discovering that pharmaceuticals ingested by humans but not fully processed by our bodies are eventually ending up in the fish we eat.

Many ocean pollutants are released into the environment far upstream from coastlines. Nitrogen-rich fertilizers applied by farmers inland, for example, end up in local streams, rivers, and groundwater and are eventually deposited in estuaries, bays, and deltas. These excess nutrients can spawn massive blooms of algae that rob the water of oxygen, leaving areas where little or no marine life can exist. Scientists have counted some 400 such dead zones around the world.

Solid waste like bags, foam, and other items dumped into the oceans from land or by ships at sea are frequently consumed, with often fatal effects, by marine mammals, fish, and birds that mistake it for food. Discarded fishing nets drift for years, ensnaring fish and mammals.

In certain regions, ocean currents corral trillions of decomposing plastic items and other trash into gigantic, swirling garbage patches. One in the North Pacific, known as the Pacific Trash Vortex, is estimated to be the size of Texas. A new, massive patch was discovered in the Atlantic Ocean in early 2010.

100,000,000 Tonnes of Marine Debris!

Marine debris is mainly discarded human rubbish which floats on, or is suspended in the ocean. Eighty percent of marine debris is plastic – a component that has been rapidly accumulating since the end of World War II. The mass of plastic in the oceans may be as high as 100,000,000 Tonnes!

Discarded plastic bags, six pack rings and other forms of plastic waste which finish up in the ocean present dangers to wildlife and fisheries. Aquatic life can be threatened through entanglement, suffocation, and ingestion.

Fishing nets, usually made of plastic, can be left or lost in the ocean by fishermen. Known as ghost nets, these entangle fish, dolphins, sea turtlessharks, dugongs, crocodiles, seabirds, crabs, and other creatures, restricting movement, causing starvation, laceration and infection, and, in those that need to return to the surface to breathe, suffocation.

Plastic debris, when bulky or tangled, is difficult to pass, and may become permanently lodged in the digestive tracts of these animals. Especially when evolutionary adaptions make it impossible for the likes of turtles to reject plastic bags, which resemble jellyfish when immersed in water, as they have a system in their throat to stop slippery foods from otherwise escaping. Thereby blocking the passage of food and causing death through starvation or infection.

Plastic debris tends to accumulate at the centre of ocean gyres. An ocean gyre is a large system of circular ocean currents formed by global wind patterns and forces created by Earth’s rotation.

The following are the 5 most notable gyres….

  • Indian Ocean Gyre.
  • North Atlantic Gyre.
  • North Pacific Gyre.
  • Great Pacific Garbage Patch.
  • Pacific Ocean Garbage Patch.

In particular, the Great Pacific Garbage Patch has a very high level of plastic particulate suspended in the upper water column. In samples taken in 1999, the mass of plastic exceeded that of zooplankton (the dominant animal life in the area) by a factor of six.

Ninety percent plastic, this debris accumulates on the beaches of Midway where it becomes a hazard to the bird population of the island. Midway Atoll is home to two-thirds (1.5 million) of the global population of Laysan albatross. Nearly all of these albatross have plastic in their digestive system and one-third of their chicks die. Toxic additives used in the manufacture of plastic materials can leach out into their surroundings when exposed to water.

Here are the basic facts about the Pacific Ocean Garbage Patch.

  • 7 million tons in weight.
  • Twice the size of Texas!
  • Up to 3 metres deep.
  • In the Great Pacific Ocean Gyre there is 6 times more plastic than plankton, which is the main food for many ocean animals.
  • By estimation 80% of the plastic originates from land; floating in rivers to the ocean or blown into the ocean by wind.
  • The remaining 20% of the plastic originates from oil platforms and shipping.
  • Scientific research from the Scrips Institution of Oceanography in California U.S. shows that 5 to 10% of fish contain small pieces of plastic.

How Can You Help?

So how can we handle the problem? First we put our hands up and admit that we’ve got one! ‘There are many different ways that we can reduce our carbon footprint and reduce our negative impact on our world’s oceans. Did you know for example that some studies suggest that the world uses 60 million straws a day!

So ditch that straw and opt for a re-useable one and that’s one less that will end up in the ocean. Refill your water bottles and use cloth bags instead of plastic ones when your shopping and you’ll help minimise the disposable one use plastic items that have become a staple in modern day society.

Recycle whenever you can, and try to buy recyclable products wherever possible.

Reduce, Reuse & Recycle

Here at Crystal Dive we try to do everything to minimise our impact on the ocean. Reduce, Reuse and Recycle is our motto, and prevention works very closely alongside conservation. Working closely with Eco Koh Tao we have regular beach and sea cleanups and lectures about how to look after our ocean planet.

We encourage all students and staff to be very eco aware, and Ocean preservation and Conservation is a huge part of diving at Crystal Dive.

Author: Alexandre Guyomard (PADI MSDT)

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