How birds are spreading plastic pollution

White storks and gulls feeding at a landfill. Enrique García Muñoz (FotoConCiencia), CC BY-NC-ND

Andy J. Green, Estación Biológica de Doñana (EBD-CSIC); Manchester Metropolitan University

Hungry gulls do not only steal our chips and sandwiches. They learn our habits, and look for reliable sources of food. That includes waste treatment centres, landfill or anywhere food waste is concentrated. Many gull populations have moved inland from the coast to exploit these sources of food.

Wherever our waste is processed, gulls and other birds can forage. At landfills, gulls feed on waste before it is covered up. If there are plastic or glass pieces covered in food that are small enough, gulls will swallow them whole. Only the food itself gets digested, and when the gull flies back to its roost site, the waste gets regurgitated, polluting that site. This movement of pollutants is known as “biovectoring”.

For the first time, scientists like me are now quantifying just how much plastic and other waste is being leaked into important nature areas through the daily movements of birds.

Many lesser black-backed gulls breeding in the UK and other parts of northern Europe migrate to Andalusia in southern Spain, where they form a wintering population of over 100,000 feeding mainly in rice fields and landfills. Fortunately, many of these birds are fitted with GPS tags while breeding. This enables detailed tracking of their movements.

Fuente de Piedra lake in Málaga is a hotspot for migrating lesser black-backed gulls. This wetland has such special natural significance, it’s designated as an internationally important site under a global convention known as Ramsar. It’s most famous for the largest breeding colony of flamingos in Spain. Gulls fly up to 50 miles to landfills to feed, then fly back to roost.

By combining GPS data with waterbird counts, and analyses of regurgitated pellets, scientists have estimated that an average of 400kg of plastics, plus more than two tonnes of other debris such as glass, textiles or ceramics, are deposited by this gull species into the lake each year. This lake has no outflow, making it salty and hence flamingo friendly. Those imported plastics remain in the lake, breaking down into microplastics. They can be ingested by flamingo chicks, aquatic insects and other animals.

Two yellow-legged gulls chase a white stork that is carrying plastic in its bill, which it picked up at a landfill. Enrique García Muñoz (FotoConCiencia), CC BY-NC-ND

In coastal Andalusia, these gulls join the resident yellow-legged gulls (equivalent to our herring gulls) and a mixture of migratory and resident white storks as the three major waterbird visitors to landfills.

In the Cádiz Bay wetlands (another Ramsar site), surrounding the historical city that is now a favourite stop for cruise ships, the three species combine to spread different types and sizes of plastics into different microhabitats. Annually, 530kg of plastics are deposited into wetlands via regurgitated pellets. Although a stork is bigger, so transports more waste per bird, most of the plastic is again moved by the lesser black-backed gulls that winter there in larger numbers.

Plastic film regurgitated by a gull roosting in a field in Atherton, Greater Manchester. Kane Brides, CC BY-NC-ND

This waste ingestion has strong effects on the birds themselves, through direct mortality from diseases, choking or becoming entangled with plastics, and toxic effects of the additives within them. Then after regurgitation in pellets, those plastics are a threat to all fauna and readily enter our food supply through aquaculture and table salt production, both important in Cádiz Bay.

These studies in Spain address a problem that is ongoing all over Europe. There are no comparable quantitative studies yet in the UK, but similar problems occur wherever gulls concentrate to feed on our waste. If white storks become abundant in the UK future, they will probably visit our landfills, together with gulls and perhaps cattle egrets.

The sealing of many landfills, and improvements in waste management may have contributed to recent declines in many gull populations in the UK and elsewhere. But these problems of plastic leakage will continue so long as our consumer society generates so much waste. Reducing waste, and reusing things is better than recycling, partly because food containers may get eaten by birds before they can be recycled. Cleaning our food containers before we bin them, and composting our own food waste, can also help to reduce this phenomenon.

Andy J. Green, Professor of Freshwater Ecology, Estación Biológica de Doñana (EBD-CSIC); Manchester Metropolitan University

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

Read More........→March 29, 2026

Australia has dedicated more than 20% of its land to conservation but not where it matters most

Kakadu National Park is a well-known example of protected land. Liana Joseph/Author provided, CC BY-ND 

James Watson, The University of Queensland; Carly Cook, Monash University; Michelle Ward, Griffith University, and Ruben Venegas Li, The University of Queensland

On paper, Australia is a conservation success story.

Over the past 15 years, we’ve dedicated vast areas of land to conservation. Our primary goal has been to protect our unique plants, animals, and ecosystems. As a result, Australia now has one of the largest protected area estates in the world, covering roughly 22% of the country.

That’s an impressive achievement, and a significant step towards our goal of protecting 30% of Australia’s land by 2030.

But there’s a problem. Our new analysis shows we’re not protecting the places that matter most for Australia’s diverse wildlife and environments.

So what are we actually conserving? And what should change?

More land but no more protection

Our recent analysis of Australia’s network of protected areas shows, between 2010 and 2022, we’ve nearly doubled the amount of land under protection. Protected land refers to areas which are specifically set aside to conserve nature. However, this expansion has done little to help our most at-risk animals, plants, and ecosystems.

Our national list of threatened species, which identifies the plants and animals most at risk of extinction, illustrates this. Since 2010, we’ve only slightly increased the amount of protected land that’s home to threatened species. Based on our data, in that time this figure rose by an average of just 3%.

Worse still, 160 species have virtually no protection. That’s roughly 10% of our endangered species list. Many others species only have a very small amount of their habitat inside the fences of protected areas.

One example is the Margaret River burrowing crayfish, a critically endangered crayfish from Western Australia. Currently none of its two remaining habitats are protected.

And the Grey Range thick-billed grasswren, a bird endemic to New South Wales, is now critically endangered because of habitat loss and agriculture. However none of its habitat, found just north of Broken Hill, is formally protected.

Tragically, these are not exceptional cases. And they are exactly the plants and animals that protected areas are designed to protect.

The same is true for Australia’s ecosystems, which are geographic areas where plants and animals interact with their natural environment. Nationally, we have nearly 100 ecological communities which are listed as threatened. But in the last decade, we’ve only improved protection for a handful of these.

And some still have no protection. The critically endangered weeping myall woodlands in the Hunter Valley, Sydney’s blue gum high forest and the iron-grass natural temperate grassland of South Australia are just three examples.

So what’s gone wrong?

For decades, we’ve tended to protect land that is more remote and less productive. Our findings suggest this pattern is continuing today.

However, many of Australia’s at-risk plants, animals, and ecosystems are found in heavily modified landscapes. These include areas which have been cleared for agriculture or are close to towns and cities. But under current conservation models, we’re much less likely to protect these kinds of land.

As a result, we are expanding protected areas but not necessarily where they matter most.

Protected areas, such as Kakadu National Park, help safeguard endangered species. Liana Joseph/Author provided, CC BY-ND

To be clear, protecting some of these landscapes is incredibly valuable. This is especially true given the current and future impacts of climate change. And in Australia, we’ve done well to protect nearly half of intact ecosystems by including them in nature reserves.

But protecting intact ecosystems is just one piece of the conservation puzzle.

Getting our priorities right

Australia has committed to protect 30% of our lands and waters by 2030. This is known as the “30 by 30” target. We are also a leader in the so-called high ambition coalition of 124 countries which have pledged to meet this same target.

But to protect our biodiversity we need to focus on which land is protected, not just how much. A hectare in the wrong place will have little effect, while a hectare in the right place can be the bridge between survival and extinction.

So as Australia moves towards the “30 by 30” target, the key challenge will be ensuring we protect land strategically, not opportunistically.

The good news is, we now have the tools to do so. Australia has some of the best biodiversity data in the world. This is because the Australian government has invested in ecologists from around the country, allowing them to closely study endangered species.

However, what we’re missing is a commitment to use this information. So far, we’ve largely measured progress using one blunt metric: total area protected. This metric is easy to communicate but is dangerously misleading. It tells us very little about whether protected areas are in the right location or are being managed well.

If we’re serious about halting species extinctions within the next five years, we need to change course now. Here are three ways to do that.

• urgently protect areas of highest biodiversity value, especially the habitats of species on the brink of extinction
• prioritise under-protected ecosystems instead of those which are easiest to conserve
• start measuring success in terms of outcomes, not just area.

Without this shift, we risk meeting our “30 by 30” target while failing to save our most threatened species and ecosystems. That would be a hollow victory.

James Watson, Professor in Conservation Science, School of the Environment, The University of Queensland; Carly Cook, Lecturer Head, Cook Research Group; School of Biological Sciences, Monash University; Michelle Ward, Lecturer, School of Environment and Science, Griffith University, and Ruben Venegas Li, Research fellow, School of Environment, University of Queensland, The University of Queensland

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

Read More........→March 25, 2026