A few weeks ago, the world woke to the story of Henderson Island, the “South Pacific island of rubbish”. Our research revealed it as a place littered with plastic garbage, washed there by ocean currents.
This was a story we had been waiting to tell for more than a year, keeping our discoveries under wraps while we worked our way through mountains of data and photographs.
Everyone wanted to know how the plastic got there, and fortunately that is a question that our understanding of ocean currents can help us answer. But the question we couldn’t answer was: when did it all start to go so wrong?
This is the million-dollar question for so many wild species and spaces – all too often we only notice a problem once it’s too big to deny, or perhaps even solve. So when did Henderson’s sad story start? The answer is: surprisingly recently.
An eloquent photo
During our research we had reached out to those who had previously worked on Henderson Island or in nearby areas, to gain a better understanding of what forces contributed to the enormous piles of rubbish that have floated to Henderson’s sandy beaches.
Then, after our research was published and the world was busy reading about 37 million plastic items washed up on a remote south Pacific island, we received an email from Professor Marshall Weisler from the University of Queensland, who had seen the news and got in touch.
In 1992, he had done archaeological surveys on Henderson Island. The photos he shared from that expedition provided a rare glimpse into the beginning of this chapter of Henderson Island’s story, before it became known as “garbage island”.
There are only 23 years between these two photos, and the transformation is terrifying – from pristine South Pacific gem to the final resting place for enormous quantities of the world’s waste.
Remember, this is not waste that was dumped directly by human hands. It was washed here on ocean currents, meaning that this is not just about one beach – it shows how much the pollution problem has grown in the entire ocean system in little more than two decades.
To us, Henderson Island was a brutal wake-up call, and there are undoubtedly other garbage islands out there, inundated and overwhelmed by the waste generated in the name of progress. Although the amount of trash on Henderson is staggering – an average of 3,570 new pieces arrive each day on one beach alone – it represents a minute fraction of the rubbish produced around the globe.
In the wake of the story, the other big question we received (and one we should have seen coming) was: can I help you clean up Henderson Island? The answer is no, for a very long list of reasons – some obvious, some not.
To quote a brilliant colleague, what matters is this: if all we ever do is clean up, that is all we will ever do. With thousands of new plastic items washing up on Henderson Island every day, the answer is clear.
The solution doesn’t require travel to a remote island, only the courage to look within. We need to change our behaviour, to turn off the tap and stem the tide of trash in the ocean. Our oceans, our islands, and our planet demand, and deserve it.
However difficult those changes may be, what choice do we have?
Prevention, not cure
While grappling with the scale of the plastics issue can at times be overwhelming, there are simple things you can do to make a difference. The solutions aren’t always perfect, but each success will keep you, your family, and your community motivated to reduce plastic use.
First, ask yourself this: when did it become acceptable for something created from non-renewable petrochemicals, extracted from the depths of the Earth and shipped around the globe, to be referred to as “single use” or “disposable”? Your relationship with plastic begins with the language you use.
But don’t stop there: here are a couple of facts illustrating how you can challenge yourself and make a difference.
- Australians throw away an estimated 30 million plastic toothbrushes every year.
Challenge: switch to bamboo toothbrushes, which cost just a few dollars each and are available from a range of online retailers or wholefood shops.
- A single bottle of typical exfoliating face or body scrub contains 300,000 plastic microbeads.
Challenge: switch to products that use crushed apricot kernels, coconut shell, coffee grounds, or sea salts as natural exfoliants.
These are only small changes, and you can undoubtedly think of many more. But we need to start turning the tide if we are to stop more pristine places being deluged with our garbage.
A remote South Pacific island has the highest density of plastic debris reported anywhere on the planet, our new study has found.
Our study, published in the journal Proceedings of the National Academy of Sciences, estimated that more than 17 tonnes of plastic debris has washed up on Henderson Island, with more than 3,570 new pieces of litter arriving every day on one beach alone.
It is estimated that there are nearly 38 million pieces of plastic on the island, which is near the centre of the South Pacific Gyre ocean current.
A 2014 paper published in the journal PLOS One used data from surface water all over the world. The researchers estimated that there are 5.25 trillion pieces of plastic in the top 10 centimetres of the world’s oceans.
Plastics pose a major threat to seabirds and other animals, and most don’t ever break down – they just break up. Every piece of petrochemical-derived plastic ever made still exists on the planet.
It is wet season in Bali, Indonesia, a popular tourist destination for Australian, Russian, German, Chinese and Japanese visitors.
As the rain pounds down on banana leaves and rice fields, the rivers fill up and irrigation systems overflow. With it, the water masses bring trash in bulk: anything from food wrappers and plastic bags to bottles and other domestic waste.
To tackle the issue of marine pollution, several organisations got together in Nusa Dua – a popular tourist destination – and other locations across Bali to stage the largest beach clean-up the island has seen.
Around 12,000 volunteers collected 40 tons of garbage at 55 locations, according to the One Island, One Voice campaign page.
While the beach clean-up was a hugely successful awareness campaign and a great promotion which highlights the efforts done around the island, it is only a drop in the ocean of global marine pollution.
Plastic pollution in Indonesia
In recent years, Bali has seen growing environmental problems such as pollution and freshwater scarcity. Popular tourist destination Kuta beach is regularly covered in waste. Most of this is plastic that washes ashore during the rainy season.
The island’s garbage dumps are reportedly overflowing,. This makes solid waste management a pressing issue. Substantial groundwater resources are predicted to run dry by 2020, threatening freshwater resources.
On top of that, Indonesia is the world’s second-biggest marine polluter after China, discarding 3.22 million metric tons of waste annually. This accounts for 10% of the world’s marine pollution.
The effects marine pollution has on ecosystems and humans are beginning to be well documented. Marine scientists have found harmful consequences of marine pollution to sea life, ecosystems and humans.
Plastic can kill ocean mammals, turtles and other species that consume it. It can also poison food and water resources, as harmful chemicals leach out of the plastic.
It poses threats to human health as well. Plastics leach cancerous toxins. After being consumed by marine species, they enter the food chain, eventually ending up in fish we eat.
Marine plastic pollution is a global problem and Indonesia’s beaches present pressing examples to study the socio-economic effects this has on coastal communities.
Most vulnerable to marine pollution left out of global discussions
Last month, The Economist held the fourth Oceans Summit in Bali.
The summit was attended by state leaders such as Indonesian Vice President Jusuf Kalla, representatives of major global economic organisations such as Citigroup managing director Michael Eckhart, and celebrity and entrepreneur Adrian Grenier.
Speakers and panels discussed a number of topics, including the “blue economy” and how companies and governments can participate in this marine-based sustainable industry.
During the summit, the Indonesian government announced it will pledge US$1 billion to curb ocean waste by 70% by 2025. It’s an ambitious objective, which shows dedication and commitment to a plastic-free future.
But not all voices are heard in this global debate. Many Bali-based environmental organisations engaged in education programs were not represented at the summit. Those economically most vulnerable to pollution – such as beach vendors, fishermen and others employed in the marine tourism trade – appear to be left out of the conversation.
Marine pollution and tourism
The Indonesian government plans to boost tourism and increase national visitors from 9.7 million in 2015 to 20 million by 2020. Such increases in visitor numbers and population will raise consumption and waste production, further pressuring the island’s infrastructure and ecosystems.
With tourism as the island’s largest economic sector, many Balinese people depend on foreign visitors to earn an income. Some tourism operators are concerned that if the plastic problem increases it will damage this industry. They fear tourists will stop coming to Bali if it is too polluted.
Marine communities may also suffer negative socio-economic consequences, as fishermen can lose their livelihood and tourism operators lose their customers.
While some tourism operators understand that clean beaches are key in attracting international tourists, the expected growth is likely to further stress Bali’s environment.
What is being done?
Efforts by activists, community groups and NGOs to clean beaches play a key role in protecting Bali’s environment. But they are only a temporary fix and don’t tackle the causes of this global problem.
Such groups are leading the fight against over-development and pollution through protests, clean-up events and educational programs.
Campaigners from Bali-based environmental youth group “Bye Bye Plastic Bags” advocate for an island-wide ban on plastic bags. They also spoke at the Ocean Summit.
And while they convinced Bali’s governor to commit to make the island plastic-bag-free by 2018, continued development of legislation, regulation and industry guidelines is needed to save Indonesia’s waterways from drowning in waste.
Microbes – bacteria and other single-celled organisms – may be tiny, but they come in huge numbers and we rely on them for clean water, the air we breathe and the food we eat.
They are nature’s powerhouses but they have often been ignored. We previously lacked the capacity to appreciate truly their diversity, from micro-scales right up to entire oceans.
Recent advancements in genetic sequencing have revealed this diversity, and our research, published in Frontiers in Aquatic Microbiology this week, shows how we can use this information to understand human impacts on an unseen world – making microbes the new sentinels of the sea.
A sea of microbes
The great majority of bacteria and other microbes are extremely beneficial, performing vital roles such as recycling nutrients.
The number of bacteria on Earth is estimated at 5×10³⁰ (or 5 nonillion, if you prefer), and many of them live in the ocean. There are 5 million bacteria in every teaspoon of seawater, and more bacteria in the ocean than stars in the known universe.
There are yet more bacteria in the world’s soils and sediments, with estimates of between 100 million and 1 billion bacteria per teaspoon. These sediments are vital for recycling nitrogen, particularly in coastal sediments closest to human populations. Without bacteria and other microbes, sediments would turn into unsightly, pungent piles of waste.
Microbial services are not limited to recycling. Many microbes, including cyanobacteria, function like tiny plants by using sunlight to produce oxygen and sugars. Due to their extraordinary number in the world’s oceans, the amount of oxygen these organisms produce is equal to that of all plants on land.
Until recently, finding out just how many different types of microbes there are was relatively difficult. How do you identify and study millions of different organisms that are not visible to the naked eye?
Bacteria, for example, had to be grown in the laboratory in large colonies to be seen. But only 1-3% of bacteria can be cultured successfully.
Advances in genetics together with the development of molecular tools have allowed researchers to investigate marine bacteria in their natural environment. Microbial communities can now be grouped by the role they play in ecosystems and how these groups respond to environmental gradients.
We can use these new tools to measure ecosystem health, which is crucial to managing human impacts on our coastlines, particularly in estuaries. Early studies have found shifts in bacterial community composition to be good indicators of contaminants
Different areas of harbours, such as Sydney Harbour, have distinct bacterial communities. These patterns may be driven by circulation. The outer harbour, which is flushed with seawater on every tidal cycle, is dominated by photosynthetic cyanobacteria. The upper harbour, with less flushing and more runoff, is dominated by soil-related bacteria and those adapted to nutrient-rich environments.
In our waterways, pollutants such as metals bind to fine particles and settle as sediment. This exposes sediment-dwelling organisms to a multitude of toxic products. What effect do these toxic substances have on sediment microbes?
Recent evidence from a large survey of eight estuaries suggests that microbes are far more sensitive to contaminants than larger animals and plants. This survey also revealed that toxic substances were linked to changes in community structure and a reduction in community diversity. This is especially alarming given that a diversity of microbes is essential to nutrient recycling.
Diagnosing wounded seas
It would be great if we could use particular microbes to diagnose human impacts. For instance, certain microbes can indicate water quality.
A technique called metagenomics is revealing the true depth of microbial diversity by pooling DNA sequences from all the species in a sample. It then works backwards to construct a genetic overview of the entire community.
However, while metagenomics can give us important information about the identity of microbes in a community, it can’t tell us what they are doing or how their functions change in response to environmental stressors and human activities.
Metatranscriptomics takes the sequencing approach one step further and characterises gene expression in a microbial community, which can be linked to crucial ecosystem services such as nutrient cycling.
Similar to their use for diagnosis of ailments in humans, molecular tools are being used to diagnose human impacts on earth by observing changes in microbes across polluted and unpolluted environments. They can even detect very small amounts of toxic substances. Because of their diversity, they can potentially be used to detect a wide range of human impacts.
This allows us to identify environmental impacts early, potentially limiting greater loss in larger organisms.
With the new tools to “see” microbes and their importance, we are now perfectly poised to advance our understanding of how microbes are responding to environmental change. They are sentinels of our increasingly human-affected waterways.
Katherine Dafforn, Senior Research Associate in Marine Ecology, UNSW Australia; Emma Johnston, Professor of Marine Ecology and Ecotoxicology, Director Sydney Harbour Research Program, UNSW Australia; Inke Falkner, Community Outreach Coordinator for Sydney Harbour Research Program, Sydney Institute of Marine Science, and Melanie Sun, PhD Candidate – Environmental Research, UNSW Australia
The link below is to an article that looks at an interesting way to clean the world’s rivers.