Headphones, saw blades, coat hangers: how human trash in Australian bird nests changed over 195 years

This, if you can believe it, is part of a magpie nest.
Kathy Townsend, Author provided

Kathy Ann Townsend, University of the Sunshine Coast and Dominique Potvin, University of the Sunshine CoastEnvironmental scientists see flora, fauna and phenomena the rest of us rarely do. In this series, we’ve invited them to share their unique photos from the field.

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When we opened a box supplied by museum curators, our research team audibly gasped. Inside was a huge Australian magpie nest from 2018.

It was more than a metre wide and made up of the strangest assortment of items, including wire coat hangers, headphones, saw blades and plastic 3D glasses — a mix of detritus reflecting our modern lifestyle.

This was one of almost 900 Australian nest specimens dating back over 195 years that we inspected for our recent, world-first study.

We estimate that today, around 30% of Australian bird nests incorporate human-made materials (primarily plastics). We also noted a steady increase in nest parasites over this period.

It’s clear the types of debris the birds use has reflected changes in society over time. They highlight the unexpected and far-reaching ways Australians impact their environment, and put birds in danger.

The full magpie nest from 2018 that was collected outside a construction site.
Kathy Townsend, Author provided

The first synthetic item

Birds and humans have been sharing spaces and habitats throughout history.

It’s well known birds incorporate material from their environment into their nests, making them ideal indicators of environmental changes and human activity. It’s also well known, particularly among scientists, that museum collections can provide unique insight into environmental changes through time and space.

Compare the magpie nest above to this natural butcherbird nest from 1894. Butcherbirds are in the same family as magpies.
Dominique Potvin, Author provided

With this in mind, our international team investigated Australian museum bird nest specimens collected between 1823 and 2018. Sourced from Museums Victoria and CSIRO’s Crace Site in Canberra, we inspected a total of 892 nests from 224 different bird species.

Australian birds generate an amazing array of nest types. Rufous fantails, for example, build delicately woven structures made of fine grass and spiderwebs, while welcome swallows and white-winged choughs create nests out of mud, which dry incredibly hard and can be used year after year.

A woven egg cup nest from 1870, made of grass and spiderwebs, by the rufous fantail.
Kathy Townsend, Author provided

Fabiola Opitz, a member of our research team, measuring mudnest collected circ. 1933 of a whitewinged chough. These mudnests can last for years.
Dominique Potvin, Author provided

Before the 1950s, human-made debris found in the nests consisted of degradable items such as cotton thread and paper.

This changed in 1956, when we found the first synthetic item in a bird nest from Melbourne: a piece of polyester string. This appearance correlates with the increased availability of plastic polymers across Australian society, seven years after the end of the second world war.

Australian magpies earn their name

We also determined, based on collection date and using historical maps, whether the nests came from natural, rural or urban landscapes. And it turns out the nest’s location, when it was built, and the species that made it largely determined whether human-made materials were present.

The nest of a noisy miner found on the Sunshine Coast, Queensland, in 2020 with plastic string.
Kathy Townsend, Author provided

Our study found nests built close to urban areas or farmland after the 1950s by birds from the families Craticidae (Australian magpies and butcherbirds), Passeridae (old world or “true” sparrows) and Pycnonotidae (bulbuls) had significantly more human-made debris.

Familiar to many an urban bird enthusiast, these species tend to adapt quickly to new environments. The incorporation of human materials in nests is likely one example of this behavioural flexibility.

The research team also had access to ten bowerbird bowers from the family Ptilonorhynchidae, spanning more than 100 years. Male bowerbirds are known for creating elaborate structures, decorated with a range of colourful items to attract a mate.

A silvereye or gerygong nest from 2019.
Kathy Townsend, Author provided

In the 1890s, the birds decorated their bowers with natural items such as flowers and berries. Newspaper scraps were the only human-produced items we identified.

This changed dramatically 100 years later, where the most sought-after items included brightly coloured plastics, such as straws, pen lids and bottle caps.

A satin bowerbird collecting blue junk. Video: BBC Wildlife.

But there are tragic consequences

When birds weave non-biodegradable materials — such as fishing line and polymer rope — into their nests, it increases the risk of entanglement, amputation and even accumulation of plastics in the gut of nestlings.

For example, we found evidence of one pallid cuckoo juvenile dying in 1981 after it was entangled in plastic twine used by its adoptive bell miner parents.

This is the bell miner nest with twine that caused the cuckoo chick to die, according to the museum notes.
Dominique Potvin, Author provided

Plastic was not the only issue. We found the prevalence of nest parasites that attack the young chicks also increased by about 25% over the last 195 years.

Nest parasites can kill huge numbers of nestlings. Recent research into the forty-spotted pardalote in Tasmania, a threatened species, has shown nest parasites kill up to 81% of its nestlings.

What has caused this increase isn’t clear. However, the team determined it wasn’t directly linked to urban or rural habitat type, or the presence of human-made materials in the nest. This goes against the findings of other studies, which show a decrease of parasites in nests that incorporated items such as cigarettes.

Interestingly, we did find eucalyptus leaves might deter parasites, as nests that incorporated them were less likely to show evidence of parasitism.

An eastern yellow robin nest from 2003, with eucalyptus leaves, lichen, spider webs and no parasites. Eastern yellow robins are specialist nest builders that don’t tend to stray from using specific natural items.
Kathy Townsend, Author provided

This nest from 1932 is from an Australian magpie, using eucalyptus leaves.
Kathy Townsend, Author provided

It may be, therefore, that sticking with certain natural materials is not only better for the safety of nest inhabitants, but also may have an added effect of pest control.

Stop littering, please

While most are aware of how plastics harm sea life, our study is one of the first to show the impact goes further to harm animals living in our own backyard. If the trend continues, the future for Australian birds looks bleak.

However, we can all do something about it.

A weebill or mistletoe bird’s woven nest from 1941, with tufts of spider webs and plant fluff.
Kathy Townsend, Author provided

It is as simple as being responsible for our rubbish and supporting proposed legislation and campaigns for moving away from single-use plastics.

The team had access to nests from 224 different species, which equates to only about a quarter of Australia’s total of 830 bird species.

There is still plenty more to discover.

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Read more:
Birds on beaches are under attack from dogs, photographers and four-wheel drives. Here’s how you can help them

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Kathy Ann Townsend, Senior Lecturer in Animal Ecology, University of the Sunshine Coast and Dominique Potvin, Lecturer in Animal Ecology, University of the Sunshine Coast

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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After a storm, microplastics in Sydney’s Cooks River increased 40 fold

A litter trap in Cook’s River.
James HItchcock, Author provided

James Hitchcock, University of Canberra

Each year the ocean is inundated with 4.8 to 12.7 million tonnes of plastic washed in from land. A big proportion of this plastic is between 0.001 to 5 millimetres, and called “microplastic”.

But what happens during a storm, when lashings of rain funnel even more water from urban land into waterways? To date, no one has studied just how important storm events may be in polluting waterways with microplastics.

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Read more:
Microplastic pollution is everywhere, but scientists are still learning how it harms wildlife

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So to find out, I studied my local waterway in Sydney, the Cooks River estuary. I headed out daily to measure how many microplastics were in the water, before, during, and after a major storm event in October, 2018.

The results, published on Wednesday, were startling. Microplastic particles in the river had increased more than 40 fold from the storm.

Particles of plastic found in rivers. They may be tiny, but they’re devastating to wildlife in waterways.
Author provided

To inner west Sydneysiders, the Cooks River is known to be particularly polluted. But it’s largely similar to many urban catchments around the world.

If the relationship between storm events and microplastic I found in the Cooks River holds for other urban rivers, then the concentrations of microplastics we’re exposing aquatic animals to is far higher than previously thought.

14 million plastic particles

They may be tiny, but microplastics are a major concern for aquatic life and food webs. Animals such as small fish and zooplankton directly consume the particles, and ingesting microplastics has the potential to slow growth, interfere with reproduction, and cause death.

Determining exactly how much microplastic enters rivers during storms required the rather unglamorous task of standing in the rain to collect water samples, while watching streams of unwanted debris float by (highlights included a fire extinguisher, a two-piece suit, and a litany of tennis balls).

Back in the laboratory, a multi-stage process is used to separate microplastics. This includes floating, filtering, and using strong chemical solutions to dissolve non-plastic items, before identification and counting with specialised microscopes.

Litter caught in a trap in Cooks River. These traps aren’t effective at catching microplastic.
Author provided

In the days before the October 2018 storm, there were 0.4 particles of microplastic per litre of water in the Cooks River. That jumped to 17.4 microplastics per litre after the storm.

Overall, that number averages to a total of 13.8 million microplastic particles floating around in the Cooks River estuary in the days after the storm.

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Read more:
Seafloor currents sweep microplastics into deep-sea hotspots of ocean life

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In other urban waterways around the world scientists have found similarly high numbers of microplastic.

For example in China’s Pearl River, microplastic averages 19.9 particles per litre. In the Mississippi River in the US, microplastic ranges from 28 to 60 particles per litre.

Where do microplastics come from?

We know runoff during storms is one of the main ways pollutants such as sediments and heavy metals end up in waterways. But not much is known about how microplastic gets there.

However think about your street. Wherever you see litter, there are also probably microplastics you cannot see that will eventually work their way into waterways when it rains.

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Read more:
Sustainable shopping: how to stop your bathers flooding the oceans with plastic

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Many other sources of microplastics are less obvious. Car tyres, for example, which typically contain more plastic than rubber, are a major source of microplastics in our waterways. When your tyres lose tread over time, microscopic tyre fragments are left on roads.

Did you know your car tyres can be a major source of microplastic pollution?
Shutterstock

Microplastics may even build up on roads and rooftops from atmospheric deposition. Everyday, lightweight microplastics such as microfibres from synthetic clothing are carried in the wind, settling and accumulating before they’re washed into rivers and streams.

What’s more, during storms wastewater systems may overflow, contaminating waterways. Along with sewage, this can include high concentrations of synthetic microfibers from household washing machines.

And in regional areas, microplastics may be washing in from agricultural soils. Sewage sludge is often applied to soils as it is rich in nutrients, but the same sludge is also rich in microplastics.

What can be done?

There are many ways to mitigate the negative effects of stormwater on waterways.

Screens, traps, and booms can be fitted to outlets and rivers and catch large pieces of litter such as bottles and packaging. But how useful these approaches are for microplastics is unknown.

Raingardens and retention ponds are used to catch and slow stormwater down, allowing pollutants to drop to bottom rather than being transported into rivers. Artificial wetlands work in similar ways, diverting stormwater to allow natural processes to remove toxins from the water.

Almost 14 million plastic particles were floating in Cooks River after a storm two years ago.
Shutterstock

But while mitigating the effects of stormwater carrying microplastics is important, the only way we’ll truly stop this pollution is to reduce our reliance on plastic. We must develop policies to reduce and regulate how much plastic material is produced and sold.

Plastic is ubiquitous, and its production around the world hasn’t slowed, reaching 359 million tonnes each year. Many countries now have or plan to introduce laws regulating the sale or production of some items such as plastic bags, single-use plastics and microbeads in cleaning products.

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Read more:
We have no idea how much microplastic is in Australia’s soil (but it could be a lot)

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In Australia, most state governments have committed to banning plastic bags, but there are still no laws banning the use of microplastics in cleaning or cosmetic products, or single-use plastics.

We’ve made a good start, but we’ll need deeper changes to what we produce and consume to stem the tide of microplastics in our waterways.

James Hitchcock, Post-Doctoral Research Fellow, University of Canberra

This article is republished from The Conversation under a Creative Commons license. Read the original article.

There’s no ‘garbage patch’ in the Southern Indian Ocean, so where does all the rubbish go?

Plastic waste on a remote beach in Sri Lanka.
Author provided

Mirjam van der Mheen, University of Western Australia; Charitha Pattiaratchi, University of Western Australia, and Erik van Sebille, Utrecht University

Great areas of our rubbish are known to form in parts of the Pacific and Atlantic oceans. But no such “garbage patch” has been found in the Southern Indian Ocean.

Our research – published recently in Journal of Geophysical Research: Oceans – looked at why that’s the case, and what happens to the rubbish that gets dumped in this particular area.

Every year, up to 15 million tonnes of plastic waste is estimated to make its way into the ocean through coastlines (about 12.5 million tonnes) and rivers (about 2.5 million tonnes). This amount is expected to double by 2025.

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Read more:
A current affair: the movement of ocean waters around Australia

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Some of this waste sinks in the ocean, some is washed up on beaches, and some floats on the ocean surface, transported by currents.

The garbage patches

As plastic materials are extremely durable, floating plastic waste can travel great distances in the ocean. Some floating plastics collect in the centre of subtropical circulating currents known as gyres, between 20 to 40 degrees north and south, to create these garbage patches.

The Great Pacific Garbage Patch.
National Oceanic and Atmospheric Administration

Here, the ocean currents converge at the centre of the gyre and sink. But the floating plastic material remains at the surface, allowing it to concentrate in these regions.

The best known of these garbage patches is the Great Pacific Garbage Patch, which contains about 80,000 tonnes of plastic waste. As the National Oceanic and Atmospheric Administration points out, the “patches” are not actually clumped collections of easy-to-see debris, but concentrations of litter (mostly small pieces of floating plastic).

Similar, but smaller, patches exist in the North and South Atlantic Oceans and the South Pacific Ocean. In total, it is estimated that only 1% of all plastic waste that enters the ocean is trapped in the garbage patches. It is still a mystery what happens to the remaining 99% of plastic waste that has entered the ocean.

Rubbish in the Indian Ocean

Even less is known about what happens to plastic in the Indian Ocean, although it receives the largest input of plastic material globally.

For example, it has been estimated that up to 90% of the global riverine input of plastic waste originates from Asia. The input of plastics to the Southern Indian Ocean is mainly through Indonesia. The Australian contribution is small.

The major sources of riverine input of plastic material into the Indian Ocean.
The Ocean Cleanup, CC BY-NC-ND

The Indian Ocean has many unique characteristics compared with the other ocean basins. The most striking factor is the presence of the Asian continental landmass, which results in the absence of a northern ocean basin and generates monsoon winds.

As a result of the former, there is no gyre in the Northern Indian Ocean, and so there is no garbage patch. The latter results in reversing ocean surface currents.

The Indian and Pacific Oceans are connected through the Indonesian Archipelago, which allows for warmer, less salty water to be transported from the Pacific to the Indian via a phenomenon called the Indonesian Throughflow (see graphic, below).

Schematic currents and location of a leaky garbage patch in the southern Indian Ocean: Indonesian Throughflow (ITF), Leeuwin Current (LC), South Indian Counter Current (SICC), Agulhas Current (AC).
Author provided

This connection also results in the formation of the Leeuwin Current, a poleward (towards the South Pole) current that flows alongside Australia’s west coast.

As a result, the Southern Indian Ocean has poleward currents on both eastern and western margins of the ocean basin.

Also, the South Indian Counter Current flows eastwards across the entire width of the Southern Indian Ocean, through the centre of the subtropical gyre, from the southern tip of Madagascar to Australia.

The African continent ends at around 35 degrees south, which provides a connection between the southern Indian and Atlantic Oceans.

How to follow that rubbish

In contrast to other ocean basins, the Indian Ocean is under-sampled, with only a few measurements of plastic material available. As technology to remotely track plastics does not yet exist, we need to use indirect ways to determine the fate of plastic in the Indian Ocean.

We used information from more than 22,000 satellite-tracked surface drifting buoys that have been released all over the world’s oceans since 1979. This allowed us to simulate pathways of plastic waste globally, with an emphasis on the Indian Ocean.

Global simulated concentration of floating waste after 50 years.
Mirjam van der Mheen, Author provided

We found that unique characteristics of the Southern Indian Ocean transport floating plastics towards the ocean’s western side, where it leaks past South Africa into the South Atlantic Ocean.

Because of the Asian monsoon system, the southeast trade winds in the Southern Indian Ocean are stronger than the trade winds in the Pacific and Atlantic Oceans. These strong winds push floating plastic material further to the west in the Southern Indian Ocean than they do in the other oceans.

So the rubbish goes where?

This allows the floating plastic to leak more readily from the Southern Indian Ocean into the South Atlantic Ocean. All these factors contribute to an ill-defined garbage patch in the Southern Indian Ocean.

Simulated concentration of floating waste over 50 years in the Indian Ocean.

In the Northern Indian Ocean our simulations showed there may be an accumulation of waste in the Bay of Bengal.

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Read more:
‘Missing plastic’ in the oceans can be found below the surface

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It is also likely that floating plastics will ultimately end up on beaches all around the Indian Ocean, transported by the reversing monsoon winds and currents. Which beaches will be most heavily affected is still unclear, and will probably depend on the monsoon season.

Our study shows that the atmospheric and oceanic attributes of the Indian Ocean are different to other ocean basins and that there may not be a concentrated garbage patch. Therefore the mystery of all the missing plastic is even greater in the Indian Ocean.

Mirjam van der Mheen, PhD Candidate in Oceanography, University of Western Australia; Charitha Pattiaratchi, Professor of Coastal Oceanography, University of Western Australia, and Erik van Sebille, Associate Professor in Oceanography and Climate Change, Utrecht University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Pristine paradise to rubbish dump: the same Pacific island, 23 years apart

The same beach on Henderson Island, in 1992 and 2015.

Jennifer Lavers, University of Tasmania and Alexander Bond, Royal Society for the Protection of Birds

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.

Our May 2017 video story detailing the rubbish on Henderson Island.

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”.

Henderson Island in happier times.
Marshall Weisler, Author provided

The same stretch of beach in 2015.
Jennifer Lavers, Author provided

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.

Cleanup confounded

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.

Jennifer Lavers, Research Scientist, Institute for Marine and Antarctic Studies, University of Tasmania and Alexander Bond, Senior Conservation Scientist, Royal Society for the Protection of Birds

This article was originally published on The Conversation. Read the original article.

This South Pacific island of rubbish shows why we need to quit our plastic habit

Jennifer Lavers, University of Tasmania

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.

Our study probably actually underestimates the extent of plastic pollution on Henderson Island, as we were only able to sample pieces bigger than two millimetres down to a depth of 10 centimetres. We also could not sample along cliffs.
Jennifer Lavers, Author provided

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.

Henderson Island, marked here by the red pin, is in the UK’s Pitcairn Islands territory and is more than 5,000 kilometres from the nearest major population centre. That shows plastic pollution ends up everywhere, even in the most remote parts of the world.
Google Maps

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.

Jennifer Lavers, Research Scientist, Institute for Marine and Antarctic Studies, University of Tasmania

This article was originally published on The Conversation. Read the original article.

Media Release: Cleaning up Barrington Tops State Forest

The link below is to a media release concerning the Barrington Tops State Forest and rubbish dumping.

For more visit:
http://www.forestrycorporation.com.au/media/releases/cleaning-up-barrington-tops

Yacaaba Headland Walk

Kevin's Daily Photo, Video, Quote or Link

I ran out of time yesterday to post about my walk up Yacaaba Headland and how I only just avoided being in a storm that was moving in. So today (it’s actually the 27th July 2012 as I type away) I must get two days of posts done, even if I slip this one in back in time, so to speak (as you can with the post time when posting).

So I decided to do the Yacaaba Headland walk just before lunch and had lunch in the carpark, while reading the paper. Nothing too healthy – I tend to eat far too much junk when I’m on holidays. So it was a bacon & egg roll, as well as a couple of potato scallops and some chips (and coke of course) See Picture at Left. It was really brunch and I needed the energy boost to accomplish the walk. Sounds…

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Mount Everest to be Given a Clean Up

The world’s highest mountain, Mount Everest, is to be given a clean up. Everest, which was first climbed by Edmund Hillary in 1953, has become something of a garbage tip. Everything from climbers rubbish to dead bodies has been left on the mountain. Now a Nepalese expedition made up of twenty Sherpa mountaineers and eleven support crew is seeking to remove some of the garbage left behind since that first ascent.

The government of Nepal wants to clean up the popular tourist attraction, bringing down rubbish that includes old tents, climbing equipment and the odd body. Global warming has led to much of the rubbish (and several bodies) no longer being covered by snow and ice.

Over 300 people have been killed attempting the climb to the top of the world, the Mount Everest summit.

For more on this story, see the Reuters article at:

http://af.reuters.com/article/worldNews/idAFTRE63I0XE20100419