The thrum of thousands of black soldier flies reverberates around the laboratory. Stacked in rows nearby are boxes containing larvae at various stages of development. Some, just hatched, are so small as to be almost invisible. Others, kept a couple of metres away, are the creatures they will become in less than two weeks: fat grubs that are 7,000 times larger — and ready for harvest.
“When they’re dried and ground into powder, it smells like a mixture of mushroom, soil and macadamia nut,” says Keiran Olivares Whitaker, 39, founder and CEO of Entocycle, the leading British tech company farming these larvae. “And when you taste it, it’s like pork scratchings.”
But you can’t taste Entocycle’s end product yet, because the sale of farmed insects for human consumption isn’t allowed in the UK (though several applications to the Food Standards Agency for black soldier fly protein to be allowed on sale, as a “novel” food, are expected to be approved soon). Instead, it is intended as a high-protein, low-carbon replacement for animal feeds currently based mainly on soya or fish meal, the sourcing of which is causing rampant deforestation and declining seafood populations.
The race to embrace insect farming has never seemed so urgent. According to the World Economic Forum and its post-Covid “Great Reset” initiative, insects are an overlooked source of protein whose consumption will help limit climate change. Last year, the global market for insect protein was worth around $1.5 billion — and, according to “Food Revolution”, a report by Barclays Research, it will grow to $8 billion by 2030.
Certainly, the environmental drivers for insect farming are powerful. Producing insect protein requires one-tenth of the feed, water and land needed for beef production, and it results in only 1% of the greenhouse gas emissions. This is because the food needed to produce all this sustainable insect protein could come largely from waste — the black soldier fly can live off almost anything — and we’ve never wasted more food.
So why not let insects use that waste and bring it back into the food chain? Well, because some scientists and animal welfare groups argue that farming insects could be cruel. And if it is, the sheer numbers of creatures affected by it would be enormous.
According to a paper authored by some of the world’s most prominent biologists and bioethicists published last year and entitled “Can insects feel pain?”, evidence is growing that some insect species (only a tiny fraction has yet been researched) are sentient, to a greater or lesser degree, and so can experience some feelings, including pain. And if they can, the argument goes that they should be brought into line with other farmed animals when it comes to welfare regulations governing the way they are reared and killed. At present, there is none.
“All of the cows, chickens, turkeys, pigs and sheep slaughtered each year amount to about 80 billion animals, whereas there’s already well over a trillion insects being slaughtered every year,” says Dr Andrew Crump, one of the paper’s authors and a lecturer in animal cognition and welfare at the Royal Veterinary College. “There are 300 million beef cows slaughtered every year, but 300 billion mealworms. The numbers are huge, so the issue is that if we get it wrong with welfare, we’re leading to suffering on this absolutely gigantic scale. The problem is that the basic kind of welfare knowledge just isn’t there. With insect farming, we’re basically where we were with conventional farming more than 50 years ago.”
Determining whether an insect feels pain is not as easy as it may sound, because behaviour that might look as if a creature is experiencing it could be put down to a physiological reaction called nociception. The paper on insect pain, published last October in Advances in Insect Physiology, explains: “Nociception does not require pain: hand withdrawal from a hot stove is a nociceptive reflex controlled by neurons relaying signals from the nociceptors in the hand, to the spinal cord, and back again. All this happens before nerve impulses reach the brain (where pain is experienced). Thus, when animals display nociception, this does not necessarily demonstrate that they can feel pain.”
One experiment conducted by Dr Crump and his colleagues found clear evidence that bumblebees can feel pain. (There is no likelihood that bees will be farmed for food other than honey, but that doesn’t make the experiment any the less significant.) Describing the findings, the academics wrote: “We gave bumblebees four feeders: two heated and two unheated. Each feeder dispensed sugar water, which bumblebees love. When every feeder had the same concentration of sugar water, bees avoided the two heated feeders. But when the heated feeders dispensed sweeter sugar water than the unheated feeders, bumblebees often chose the heated feeders. Their love of sugar outweighed their hatred of heat. This suggests bees feel pain, because (like humans) their responses are more than just reflexes.”
They also concluded that flies could experience pain, again because of their reaction to heat. “Hungry flies are less likely to jump away from extreme heat than satiated flies,” they wrote. “Decapitated flies can still jump, but they do not display this difference, demonstrating their brain’s involvement in heat avoidance. Communication between the brain and the responsive body part is also consistent with pain.”
Last year, the Animal Welfare (Sentience) Act included the first invertebrates to be given farming protections: decapod crustaceans, including crabs, lobsters and prawns, and cephalopods, including squid and octopuses. Their inclusion came largely as a result of a sentience framework drawn up by a team of researchers led by Dr Jonathan Birch, associate professor of philosophy at the London School of Economics and principal investigator on the university’s Foundations of Animal Sentience project.
The framework has eight criteria ranging from whether an animal has nociceptors and integrative brain regions to whether it can trade off threat of injury against opportunity for reward, or whether it responds to local anaesthetics or analgesics. No single criterion is proof that it can feel pain, but combinations of some of them may suggest that it can. Octopuses satisfied seven out of the eight criteria; squid and cuttlefish satisfied four; crabs five; and lobster three.
The “Can insects feel pain?” paper, of which Dr Birch was a co-author, concluded that flies and cockroaches satisfied six of the criteria, which amounts to “strong evidence” for pain. Other insects met fewer of the criteria, yet the researchers concluded that there was “substantial evidence” they could experience pain. Ants, wasps and bees met four criteria, and crickets, grasshoppers, butterflies and moths met three.
Perhaps surprisingly, not all environmentally conscious and animal-friendly groups support insect farming, in spite of its many obvious advantages. When I asked People for the Ethical Treatment of Animals (PETA) what they thought of it, they simply replied that we could get all the protein we needed from plants. Elsewhere, Phil Brooke, Compassion in World Farming’s research and education manager, argues that feeding animals protein from insects makes the food chain less efficient: “Less than 40% of the protein you feed to a chicken ends up in the meat you eat. If you feed a salmon, it’s only 28%. If you feed a pig or a trout, it’s just over 20%. And it can be lower for other species. It’s the simple law of ecology that at each stage in a food chain, you lose energy. So if you’re feeding flies on waste food, we think it would be better to simply feed that waste food directly to animals, like pigs, and miss out a layer.”
Back at Entocycle, tucked away in a railway arch a stone’s throw from London Bridge, I put all of these points to Olivares Whitaker, who has a degree in environmental design and conservation. He seems unfazed: “The phrase ‘plenty more fish in the sea’ is a complete fallacy. The latest data says we have exhausted more than 51% of all fish. We have destroyed the coral reefs, the nurseries of the ocean. By messing up the coral reefs, you mess up the juvenile fish populations, and if you mess up the juvenile fish populations, you mess up all the seabirds, you mess up the seabirds, you mess up the ecosystem.
“Our rainforests are being cut down for large monoculture crops. What most people don’t realise is that 90% of all soy that’s brought to the UK doesn’t go into your soy burger or your soy milk. It goes straight in to feed the cow, straight in to feed the pig, straight in to feed the chicken. And it’s really unhealthy for most animals to be eating this stuff. They’re being force-fed rations which are the lowest cost to the highest value.
“I couldn’t sit back and just watch that, so I began looking at insects. How do insects currently act in the food web? Because the rotting apple falls from the tree, the insect eats the apple, the bird eats the worm, and off we go up the food web. It’s just normal. Every single animal on this planet, including humans, has been eating insects for millions of years.”
While Entocycle used to farm larvae for the pet-food industry, its focus today is on designing insect farms that ensure the greatest ratio of “protein in” to “protein out” – and, yes, to achieve the highest levels of welfare based on the company’s own research. And, so far, this mission is selling well. It has, for instance, recently attracted £4.2 million in funding from US investors and £3.3 million from Innovate UK, a government-backed body that provides money and support to industry. Meanwhile, Olivares Whitaker’s team of 35 engineers, designers, computer specialists and entomologists have contracts to design facilities in the Middle East and the UK that will produce thousands of tonnes of protein each year. And, as a welcome by-product, almost half of each farmed larvae contains excrement that can be used as a rich fertiliser.
“We are now facing a fertiliser crunch,” Olivares Whitaker says. “People don’t realise that the fertiliser industry is screwed since the war in Ukraine, and prices have quadrupled. Here, we have a perfect, organic and sustainable way of producing high-quality fertiliser using black soldier flies feeding on waste.”
But what about welfare concerns, and the claim that farming insects is inefficient? “Waste isn’t perfect,” he says. “You can’t just feed any waste to animals — for example, we saw with cows and BSE what happened when we fed them waste derived from other animals. Farmers need to know exactly what is in the protein they are feeding their animals. You can’t just feed anything to, say, pigs. But black soldier flies could feed off anything and turn it into high-quality protein.”
At present, however, UK rules don’t allow flies to be farmed that have been fed on excrement, but they could be — and the end product would be perfectly safe for animals and even humans. In developing countries with sewage disposal and protein security problems, governments are already looking at the possibilities of farming with insects.
So, what about the welfare side of the argument? I direct Olivares Whitaker to a paper written by Dr Meghan Barrett, another co-author of “Can insects feel pain?”, entitled “Challenges in farmed insect welfare”, in which she argues that farmed black soldier flies are susceptible to five welfare issues: nutritional inadequacies, larval overcrowding and overheating, unmet needs for mating behaviour, starvation, and inhumane slaughter.
But he’s having none of it. “If you get any of those five requirements wrong, your farm simply won’t work. If you starve your flies, they’re not going to breed your next generation of larvae. If you don’t meet their needs for mating behaviour, you’ll have nothing to farm. The welfare of the insects goes hand in hand with how successful and productive your operation will be.”
What if the government legislated to include insects in farming welfare regulations — would the industry comply? “I personally would welcome welfare regulations,” says Olivares Whitaker. “If you didn’t care for every aspect of their needs, your farming system simply wouldn’t work and you’d be out of business.”
I asked the Department for Environment, Food and Rural Affairs if it had any plans to bring insect farming into line with other types of animal farming welfare, but it didn’t reply. Perhaps ministers are concerned that the public isn’t ready for insects to be deserving of concern. That might be true, but it’s hard to argue in a protein-insecure world that Olivares Whitaker is wrong. And one day soon, it won’t just be animals being fed on insects — we’ll be eating them, too.