Health Of The Oceans

What Is The Problem?

The degradation of the health of our oceans is, perhaps, the most important environmental issue on the global agenda. Many believe that if we focus on saving our oceans, then we will save our planet. Here we discuss the key issues impacting ocean health and provide some helpful advice we can all follow to help address this.

Littering and plastic pollution is severely impacting the health of our oceans. A lack of bins on footpaths and roads means that litter can originate from pretty much anywhere, but pedestrians and motorists are mostly to blame. If not disposed of correctly, litter can end up in our oceans and lead to the entanglement of plants and wildlife. If ingested, litter can be highly toxic to animals; cigarette filters, for example, are ultimately a poison pill when consumed by wildlife. They account for 50% of all littering and take up to 10 years to decompose. Many sewage systems are also not designed to filter out some plastics often flushed down the toilet, such as cotton buds and tampons, resulting in these items ending up in the ocean.

When plastic enters the ocean, sea salt causes it to degrade rapidly, becoming microplastics (plastics under 5mm in diameter). These tiny plastics are also found in many exfoliant products. Microplastics are known to have been ingested by many marine species, even microscopic phytoplanktons. These microplastics and harmful toxins are passed through different species, resulting in them building up in the food chain. They have even been identified in fish fillets and shellfish that we eat. In 2020, a new crustacean species, discovered at a depth of 6500m, was found to have microplastics in its digestive system, further cementing the scale of the problem. The new species was subsequently named Eurythenes plasticus.

In areas of the ocean where the water is stationary “plastic islands” have started to form. The largest of these islands is located between California and Hawaii and is best known as the Great Pacific Garbage Patch (GPGP); it contains 8000 tonnes of plastic - the equivalent weight of 500 jumbo jets - and is three times the size of France!

The extent of plastic pollution in our oceans is posing a significant threat to the survival of our marine wildlife. As many as 700 species are believed to have already encountered marine debris, a figure that will continue to rise, with research suggesting as many as 100 million marine mammals die every year as a result of plastic in the ocean.

Climate change is another key issue impacting the health of our oceans. The ocean plays a critical role in controlling the temperature of the planet, however, as the Earth warms at an alarming rate so does the ocean. This is having a significant impact on the health of coral reefs on a global scale. Rising ocean temperatures evoke a stress response in coral reefs called coral bleaching. Bleached corals can recover if more favourable conditions return, but this needs to happen quickly to prevent the corals from starving.

Climate change is also making the ocean more acidic as it absorbs increasing levels of carbon dioxide from the atmosphere. This negatively impacts any shelled organisms and corals whose skeletons are made of calcium carbonate as this dissolves in acid. As a result, over the last 50 years we have lost over 50% of our coral reef systems.

Not only do coral reefs support a large range of marine life, they also play an important role in protecting our shores from coastal erosion and control the frequency of extreme weather events. If we continue to ignore the problems in our reefs we face the destruction of a key ecosystem, loss of many species and, closer to home, impacts to coastal communities and their livelihoods.

Sunscreen

Believe it or not, sunscreen is also having an impact on ocean health. Up to 14,000 tonnes of sunscreen wash into the ocean each year, along with many other personal-care products. Sunscreen can contain a chemical called oxybenzone which detrimentally affects coral reproduction and growth cycles, and can ultimately result in the bleaching and death of coral reefs. Although in the UK we do not have tropical coral reefs, we are home to many species of cold water corals and for all of the reasons discussed above, it is more important than ever to protect all coral species in our oceans.

How You Can Help

With whale populations on the rise and many countries banning and taxing single use plastics the ocean has an amazing ability to recover from many environmental issues. If we act today there is the potential that 50-90% of marine life will recover by 2050. Our ocean has the potential to help us fight climate change, reduce our environmental footprint and remove the pressure from our land. A healthy ocean will lead to a healthier planet.

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