Illegal waste dumping in the UK is no longer a marginal nuisance. It is increasingly operating at an industrial scale, with serious consequences.

The reported dumping of around 30,000 tonnes of waste at a protected site of special scientific interest in Leicestershire is one recent example of how severe the problem has become. Similar concerns have emerged recently at the large illegal waste site near Kidlington, Oxfordshire, where shredded mixed waste was deposited close to waterways. These are signs of a broader waste-crime economy that is damaging land, water and communities while shifting the bill onto the public.

The House of Lords environment and climate change committee estimated that waste crime costs the UK economy about £1 billion a year.

Part of the problem is that by the time large fly-tipping sites are discovered, it can be difficult to identify the original source.

This is where digital technology and geospatial intelligence are becoming increasingly important.

My ongoing research focuses on exactly this problem: mapping and characterising uncontrolled waste disposal sites worldwide, and using satellite data, geospatial intelligence and AI to identify where they are, how large they are and what risks they pose to nearby people and ecosystems. The principle is simple: you cannot manage what you cannot measure. If waste crime is going to be tackled properly, the sites have to be found first.

Satellite imagery and remote sensing now allow researchers and regulators to monitor land-use change, detect unusual waste accumulations, and identify environmental risks at scales impossible through traditional inspections alone, as demonstrated by recent work using satellite imagery and AI to identify dumpsites in 28 cities.

How would it work?

Drones can provide high-resolution imagery of suspect sites, while AI systems can analyse patterns and flag high-risk activity quickly. To do this, they will build on advances in waste-site detection from aerial and satellite imagery.

Thermal imaging and technologies to detect methane can also identify emissions from decomposing waste that would otherwise remain invisible. Recent studies show the growing capability of satellite-based methane monitoring to identify major emission sources and help create more effective waste-sector policies.

These tools are especially valuable because most large illegal waste sites do not appear overnight. They grow gradually over months or years, so earlier detection creates an opportunity to get on top of the problem before environmental damage escalates.

While these technologies are not usually sufficient on their own to identify individual offenders, they can provide evidence of when and where illegal dumping occurs, help authorities monitor sites over time, and support targeted investigations and enforcement actions. Their value is often in enabling earlier intervention.

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Read more: Dirty gold: the fly-tipping gangs costing councils millions – and how you can help

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The UK government is due to launch a digital waste tracking service in October 2026, replacing outdated paper-based systems with real-time digital reporting.

Official waste operators will then have to create records of receipt of waste, or face fines. If implemented effectively, the system could improve traceability across the waste chain and make it far harder for waste to disappear into illegal sites unnoticed. The government is already starting to use drones to help track down waste dumpers.

How big is the problem?

Local authorities in England dealt with 1.26 million fly-tipping incidents in 2024-25, a 9% increase from the previous year. However, the total number of court fines decreased by 9% over the same period.

Analysis reported by the Guardian suggested the UK may now have around 8,000 illegal waste sites and those that dumped the waste have avoided about £1.63 billion in landfill tax.

Globally, a report from the UN Environmental Programme estimated the hidden costs of uncontrolled waste disposal reached US$243.3 billion (£181 billion) worldwide in 2020.

The environmental damage depends on quantity, composition, location and how long waste remains in place. Illegal sites often contain mixed household rubbish, plastics, construction debris, shredded material, and sometimes hazardous waste. As this material degrades, it can cause damage to water, soil, air and possibly human health, preliminary research suggests.

Without impermeable barriers or drainage, polluted leachate (contaminated liquid generated by waste) can move into soils, rivers and groundwater. There’s considerable risk in floodplains and other sensitive areas, where heavy rain can carry pollution further and faster.

What are the problems caused by dumps?

Illegal dumps can also attract pests and other disease carriers, creating public health concerns, disturbing habitats and harming wildlife. Animals may ingest plastics and other harmful materials, while the wind can spread shredded waste across nearby land.

In some cases, waste can catch fire, releasing smoke and fine particulates into the air. In addition, when organic waste decomposes in the absence of oxygen, it produces methane, a potent greenhouse gas.

The economic cost is equally severe. Cleaning up major illegal dumpsites is technically difficult and extraordinarily expensive. Authorities must map the site, assess contamination risks, identify hazardous materials, secure the area, and safely remove and process the waste.

In sensitive locations such as river corridors or floodplains, sorting out the problem becomes even more complex. The Environment Agency has warned that clearing the Oxfordshire site could cost over £7 million.

The obvious question is why this keeps happening. Part of the answer is economic. Proper waste disposal is expensive, while illegal dumping can generate large profits for individuals by illegally avoiding landfill taxes and compliance costs.

Waste also moves through fragmented supply chains involving brokers, subcontractors, carriers and temporary operators, making accountability difficult. Historically, waste tracking in the UK has relied heavily on paper documentation, creating opportunities for fraud, falsified records and waste simply “disappearing” from the system.

What next?

Technology alone, however, is not enough. Better monitoring must be combined with stronger enforcement, improved coordination between agencies, clearer accountability across supply chains, and meaningful penalties that outweigh the financial incentives of illegal dumping.

Illegal waste is not simply a waste-management issue. It is an environmental, economic and public-health issue. Allowing industrial-scale dumping to become normalised would shift enormous long-term costs onto society, ecosystems, and future generations.

Prevention, transparency and early detection are ultimately far cheaper and far less damaging than attempting to clean up after the damage has already been done.

Amani Maalouf receives funding from the UK Research and Innovation (UKRI) Digital Research Infrastructure programme, administered by the Natural Environment Research Council (NERC) on behalf of UKRI.

For captive animals, engaging in natural behaviour is a pillar of the animal welfare framework. But when it comes to sex, one important behaviour has been largely ignored, and sometimes even punished: masturbation.

Solo sex is surprisingly common across the animal kingdom. It is well documented in primates. Tortoises are surprisingly vocal during their solo lovemaking endeavours, if not very graceful. Camels masturbate by rubbing their penises in the sand and porcupines make inventive use of all sorts of objects.

Our new study could change how other scientists view masturbation in birds and improve their welfare.

Masturbation also seems to be common in birds. A quick internet search brings up an abundance of video clips on social media and dedicated posts on bird-keeping forums, largely from worried or bemused hobbyist bird keepers.

It has often been treated as an abnormal problem behaviour in captive birds (particularly parrots). Folklore husbandry has assumed it is the undesirable outcome of stress, bad health or poor environment. Bird keepers often therefore discourage masturbation via punishment or veterinary interventions such as diet or care changes and, sometimes, even drugs and surgery. Despite the welfare implications, masturbation in birds had been largely unexplored by the scientific community.

We set out to change that, by investigating the distribution and evolutionary history of masturbation in birds for the first time. We studied 120 species of bird across 22 major groups, gathering data from the scattered scientific literature, online reports and community forums, and surveys of bird experts.

Our study found that masturbation is widespread across birds with a strong evolutionary history, meaning that it’s an ancient trait probably similar in closely related species. Although we found more records of masturbation in male birds, it occurs in both sexes and across all age groups.

Solo sex also seems to be linked to species that mate with multiple partners, supporting the idea that it might help to increase reproductive success when there is a high degree of competition over fertilisation. For instance, in males it may flush out old sperm to leave newer (better condition) sperm for mating. In females it may increase sexual arousal to help with sneak mating with males other than their partner.

Wild behaviour

Crucially, we discovered that masturbation is actually less common in captivity than the wild, and more common in birds reared by their own parents than by humans. What this tells us is that masturbation in birds is neither an unnatural behaviour, nor a consequence of captivity. Given this finding, it is important that birds are not prevented from masturbation. Of course, as with any behaviour, there may be extreme cases where chronic masturbation could indicate underlying health or husbandry issues.

Avian self-pleasure is usually a rather inelegant affair, in which a bird rubs their cloaca (a shared orifice for both excretion and reproduction) against an object, like a branch, twig or toy. This is often accompanied by a lot of flapping and self-satisfied vocalisation.

One potential reason for the lack of scientific studies exploring avian masturbation may be because the cloaca is thought to have fewer nerve clusters, and therefore lower sensitivity, than our own genitals.

Clearly however, birds are getting some satisfaction from masturbation, so perhaps there is more to a bird’s sensations during sex than has previously been recognised. Further exploration of this could have important implications for both welfare and captive breeding programmes. While sexual pleasure may not be exactly the same experience as for mammals, it is wildly premature to dismiss the idea that birds also feel pleasure.

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

William Adams was entranced by energy. As a young man, his interest was nursed by working as a clerk in a London patent office in the 1860s. This gave him an early look at some of the first British designs for exploiting solar energy using mirrors, water or both.

Adams would later recount his excitement at reading about the French mathematician Augustin Mouchot’s invention of the first machine ever to run on energy from the Sun. The device, which connected a solar boiler to a specifically designed steam engine, was warmly received by Napoleon III when it was presented to the emperor in 1866.

Inspired, Adams soon designed and patented his own rudimentary solar boiler. The only problem was, he needed more sun.

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This series is dedicated to lesser-known, highly influential scientists who have had a powerful influence on the careers and research paths of many others, including the authors of these articles.

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When offered the chance to become deputy registrar of Bombay by the Indian city’s governor, Sir Philip Edmond Wodehouse, Adams jumped at the opportunity. There, he became the first Briton to design, build and test a fully-functioning solar steam engine fit for industrial purpose.

But he also came up against the conservatism of India’s colonial rulers, who did not see this Bombay bureaucrat for the energy visionary that he undoubtedly was.

‘The rays beat like missiles’

Adams arrived in Bombay in 1873 to find it in the middle of a cotton boom, with mills popping up like mushrooms across the city. The population was growing so quickly that firewood was depleted for miles around. The landscape grew “bald as a billiard ball”, as Adams put it.

Every morning before setting off for work near Bombay’s central fort, Adams would set up his outdoor laboratory at his home in the southernmost Colaba district, near the open sea. He instructed an Indian fundhi (skilled carpenter) to build a set of three-tiered wooden shelves to hold 18 looking glasses.

“Each glass was moveable on a swivel in the same manner as an ordinary toilet glass”, Adams explained, meaning he could pivot each glass by “the touch of the finger”.

Later, for open-air experiments, Adams used two banks of mirrors (36 in total) which made “the mercury in the thermometer boil, leaping up to over 670 degrees fahrenheit”. He then placed a copper cylinder containing three gallons of water in the focus of all 36 mirrors, making it boil in exactly 20 minutes.

But Adams’s ambition did not end there. To reach sufficient pressure in the boiler to drive a steam engine, this bureaucrat-cum-engineer built a giant concave mirror, 24 feet in diameter. He then sent for his London solar boiler, which was delivered by ship to Bombay in 1876.

One fine morning, Adams – wearing dark glasses for safety – turned his giant concave mirror on the copper cylinder filled with water. “The rays beat like missiles in a continuous and incessant storm of solar fire,” he wrote.

An hour later, the cylinder registered 55 pounds of pressure per square inch. He hired a steam engine of 3 horsepower and connected it to the boiler: the pressure moved the pistons. Adams had built the first working, British-designed solar steam engine.

For a fortnight, he kept the pump going near his bungalow in Colaba – proudly and sweatily displaying his innovation to government officials, newspaper reporters, mill owners and the local Indian communities. Members of the public were invited to witness his experiments too, via a notification in a Bombay newspaper.

‘An inexhaustible source of wealth’

In 1877, Adams wrote a letter to the editor of the Times of India arguing that the application of his solar steam engine would “make India the seat of the principal manufacturing industries of the world”.

Later, in his wildly ahead-of-its-time treatise Solar Heat: A Substitute for Fuel in Tropical Countries (1878), Adams argued that countries near the equator “possess, in their clear skies, a gratuitous and inexhaustible source of wealth, equal to that which western nations have to dig, with infinite labour and toil, from the bowels of the Earth”.

Adams sketched out plans to use solar heat for everything from cotton gins (engines to separate cotton fibres from seeds) to Hindu crematoria. He called upon the colonial British government to invest in this promising substitute for coal, which was then being imported to India at great expense.

Adams envisioned solar energy transforming the Raj. Just like the coal-combusting steam engine had replaced the waterwheel in England, he argued that thermal heat could now replace fossil fuels in India. But his colonial bosses were not persuaded.

‘Too subversive’

Adams was part of a 19th-century wave of global research into solar steam engines, as I explore in my postdoctoral project and upcoming book. But in contrast to fellow pioneers including Frenchman Mouchot, Adams built his solar steam engine to stimulate local Indian industry, not to benefit the colonial government.

The locals shared Adams’s belief in this technology. One even wrote to Scientific American magazine to express their desire for the rapid adoption of solar power:

My residence is in a tropical part of India … where fuel is scarce and dear … In this part of the country (about 300 miles north of Bombay), there is a great opening for cheap power in small units.

Bombay’s new governor Sir Richard Temple concluded, however, that solar heat “could not be used for commercial purposes on a large scale”. He argued that local factory owners would not like giving “the workmen a holiday on days when the sky is not clear”.

In truth, Adams’s invention was too subversive for Britain’s colonial officials and capitalists. In less sunny climes, solar energy – tethered to the seasonal rhythms of nature – might negate their commercial ambition for timeless industrial production. But they also saw India as an important market for British coal exports.

While a few mill owners adopted Adams’s auxiliary solar heater for their steam engines, most regarded it as a primitive contraption unfit to satisfy the demands of modern civilisation.

Increasingly frustrated that neither the industrial capitalists nor the colonial government supported his vision, Adams abandoned further experiments. His dream of India switching away from coal to solar power, from combustion to concentration, would not happen for at least another century.

Now, however, India is a world leader in the global energy transition. It heads the International Solar Alliance, and is the third largest solar power generator in the world.

Which begs the question: how much further advanced would this technology be had Adams’s 19th-century solar experiments been embraced by India’s colonial rulers at the time?

Sebastian Egholm Lund receives funding from the Carlsberg Foundation. His upcoming book, Changing the Climate at the Fin de Siècle, is published by Cambridge University Press (September 2026).