The smell of sea water and fresh dung fill the oceanfront air on the Kenyan island of Lamu, as donkeys plod along the town’s dock, ferrying residents and cargo. Lamu Old Town is a Unesco world heritage site, known for preserving its Swahili culture. With no cars but nearly 3,000 donkeys on the island, residents rely heavily on the animals for a living and as transport in the narrow, winding streets of the 700-year-old town, one of east Africa’s oldest.
Now, however, increasing numbers of donkeys are dying from eating plastic on the island, and scientists fear many other land animals are also being affected by human plastic pollution.
With little grass to graze on, donkeys browse for food through heaps of plastic bottles, nappies and scraps of cloth dumped by the road.
The owner of one weak and dehydrated baby donkey recently rushed the animal to the Donkey Sanctuary, an animal welfare charity. When vets gave the animal laxatives, they were troubled to find 30cm of knotted plastic wrapped up in its stool.
“The donkeys will eat all sorts of things, from plastics to clothes to cartons – everything,” says Dr Obadiah Sing’Oei, the lead vet at the Donkey Sanctuary. The animals are eating enough plastic to block their digestive tracts, leading to starvation and death.
“This brings a lot of issues … nutritional colic in donkeys is usually fatal,” says Sing’Oei.
The toll of plastic pollution on marine life is widely documented, but far less is known about the effect on terrestrial animals. In one of the first studies of its kind, researchers from the University of Portsmouth and the Donkey Sanctuary are investigating the effects of plastic pollution on animals in Kenya, focusing on donkeys and other livestock.
The team’s full results are expected to be published later this year. They record at least three donkeys a month dying from colic caused by eating from rubbish dumps – but say the true number is probably higher.
Sing’Oei says: “This is nothing, as just a fraction of colic cases are brought to the clinic. Anecdotally, if you ask any donkey owner in Lamu, they will tell you they have lost a donkey to colic from plastic.
“When owners bring their donkeys to the clinic it is as a last resort.” He says it is “fast becoming a crisis for donkey welfare”. By the time the donkeys get to the vet, Sing’Oei says many of them are writhing in pain, struggling to breathe or unable to move.
“If they came earlier, we may have been able to save them,” says Sing’Oei. “For donkeys, surgery in the abdomen is a ‘Hail Mary’ – they hardly survive.”
Hufeidha Abdul Majid, a 27-year-old donkey owner who lost one of his animals to colic in May, says: “I am really concerned about the plastics. Before, blockages were caused by organic material, so we could handle that, but that’s not the case now.”
Majid’s grandfather passed his donkeys on to him before he died, and he now owns 25 of the animals, using them to carry goods.
“To lose a donkey is hard – it’s like a family member,” he says. “I no longer leave my donkeys to roam in town because you don’t know what they will eat.”
The donkey study will form part of a growing body of research into what plastic waste is doing to animals on land, as well as the more widely known effects on sea life. “We’ve got less data on it [than on marine ecosystems], but initial work on the impact of plastics on land suggests it could be equally pervasive,” says Prof Richard Thompson, from the University of Plymouth.
In the UK, researchers in 2022 found plastic was being eaten by more than half of the small mammal species tested. The most common type was polyester – probably from clothing.
In India, scientists found rubbish in the dung of a third of elephants tested – including glass and rubber as well as plastic. In Indonesia, Portsmouth and Hasanuddin universities are launching a project to investigate how plastic affects Sulawesi moor macaques.
In many countries, domesticated animals are grazing on open waste dumps to find food. Not only does this have a dire effect on their health and welfare, but it can also affect the humans consuming their meat or milk, which can contain microplastics, says Dr Leanne Proops, a member of the Revolution Plastics research initiative at Portsmouth University.
Despite the growing concerns about links between plastic pollution and animal and human health, livestock owners on Lamu often cannot afford to feed their animals. Two years ago, researchers documented a case of a slaughtered cow on Lamu with 35kg of waste inside its stomach, including nappies and bags.
“It’s pretty grim,” says Dr Cressida Bowyer, deputy director of the Revolution Plastics initiative. “We saw what was happening and found there was no research being done in this area,” she says.
In some parts of the Lamu archipelago, residents have formed private rubbish collection associations but in others, such as the Old Town, they rely on irregular county collection services. Some groups, such as the Kenyan plastic reduction organisation FlipFlopi, collect plastic trash for recycling.
“Tractors used to go every two or three days to collect rubbish and colic cases went down, but it’s overflowing again,” says Sing’Oei. “It’s something that causes a drastic change. [Colic] cases go down when the dumpsters are cleared, and rise again when they are filled up.”
“This entire town was built on the back of donkeys,” says Shebe Abdallah, 54, as he pulled up a photo of the donkey on his phone. He lost his last racing donkey to colic a few years ago.
“We don’t need to mark our donkeys because we know each one of them – the one who died was the fourth of a generation of donkeys that passed down through my family,” he says. “It’s difficult to lose one you’ve invested so much in.”
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