[This is a chapter from my forthcoming book 2% Solutions for the Planet: 50 Low-Cost, Low-Tech, Nature-Based Practices for Combatting Hunger, Drought, and Climate Change.]
One of nature’s most important and overlooked carbon farmers is also an ancient symbol of regeneration and renewal: the scarab.
It’s a beetle, a member of the family Scarabaeidae, which includes more than 30,000 different species, part of the order Coleoptera, which encompasses 400,000 species of beetles (out of the 4 to 8 million still to be classified), constituting roughly 25 per cent of all known animal species on the planet. That’s a lot of beetles! Too many to keep in mind, so you’re forgiven if you hadn’t given them much thought. There’s one type, however, that definitely deserves our attention: the dung beetle.
It certainly caught the attention of the ancient Egyptians, who elevated the lowly dung beetle to the status of a god—and for good reason. Dung beetles united three sacred elements of their culture: sun, soil, and cattle. Scarabs fly to the dung patties created by cattle and disassemble them within hours, usually by rolling the manure into brood balls—where the beetles lay their offspring—and then burying the balls below ground in tunnels and chambers where the nutrients nourish soil microbes.
The ancient Egyptians knew this activity was critical to maintaining the health and fertility of the soil on which their civilization depended, which may be why they revered the dung beetle on a level with Osiris, the god of the underworld.
Alas, the scarab is not so revered today. In fact, dung beetle populations were nearly hammered into oblivion in the mid-twentieth century by the pesticides and insecticides of industrial agriculture. Only in recent years has their benefit to nature and agricultural ecosystems been rediscovered, including the role they can play sequestering atmospheric carbon in soil. It’s also been estimated that dung beetles can save farmers billions of dollars every year. How?
The story starts with a fly—the horn fly in particular.
Most people don’t realize that manure (dung) is a coveted resource in nature, fought over by many creatures, including the pests and parasites that literally “bug” cattle and other livestock. This includes the horn fly (Haematobia irritans—or blood-loving irritant) which arrived on American shores from Europe in 1887. The flies lay their eggs in cow pats and the larvae are incubated there (for as little as five days) until they transform themselves into new adult flies and emerge to begin their torment. Among other maladies, their persistent biting can cause infections in cattle.
A century ago, however, horn flies were not the scourge they became for a simple reason: dung beetles eliminated the manure before the eggs could hatch. A bevy of beetles can bury a field of fresh manure patties in a matter of hours—no dung, no flies!
This natural balance changed dramatically after World War II when farms, rangelands, and animals began to be sprayed with various synthetic compounds in the name of pest and parasite “control.” Not coincidently, dung beetle populations dropped dramatically (being a “pest” after all), leaving a lot of poop sitting on the ground. Horn fly populations exploded.
Flies can also serve as vectors for a variety of serious diseases that infect humans, including typhoid, cholera, amoebic dysentery, and tuberculosis. One cow patty can house as many as 450 different insect species and one pair of flies can parent as many as 1.5 million new pairs in as little as 14 weeks. Flies can quickly develop resistance to insecticides as well. For all of these reasons, in the early 1970s a handful of researchers and cattle ranchers decided to reject the application of ever-more chemicals and opted to bring back the sacred scarab instead.
Lead by US government entomologist Truman Fincher, an energetic effort began to establish viable populations of two species of dung beetle, one imported from Europe (Onthophagus taurus) and one from Africa (Onthophagus gazella), the latter via Australia where livestock producers were experiencing similar problems. In Africa, research had shown that an elephant dung pile supported 48,000 beetles, who buried the dung underground within hours.
One beneficiary of this work was Texas rancher Walt Davis, an early pioneer of high-density, short-duration cattle grazing, which he found to be ideal for the cultivation of dung beetles that trailed his herd of cattle like camp followers trailing an army of soldiers. When he quit using chemicals on his ranch in 1974, the scarab moved in.
“Those beetles really got to work,” Davis said in an interview in Dung Beetles and a Cowman’s Profits by Charles Walters. “In a paddock just vacated by a herd…in 48 hours there was no manure. It was gone!”
It was another example of returning to nature’s way of doing things, in this case dung removal.
According to Fincher, few people realized the significance of the dung beetles to ecosystems. Beetles are nature’s sanitation crew, he insisted. Their quick burial of dung hastens its decomposition, prevents the loss of nutrients, aerates the soil, and increases the depth of soil containing organic material. That sounds like a recipe for building soil and sequestering carbon.
Not only do dung beetles transport carbon, nitrogen, and phosphorus underground when they remove manure, feeding the microbes a rich diet of organic food, their tunnels increase porosity in the soil, which means more water and oxygen reach the microbes as well, revving up their tiny engines. This increases storage of carbon in the soil, with important positive implications for watershed health, plant growth, food production, pollution abatement, and climate change. And all done for free—by nature!
In his book, Charles Walters points out that Onthophagus gazella was released precisely as the natural food and organic agriculture movements began to pick up steam in the US, reflecting a desire for nontoxic approaches to food production that continues to this day. “The mere existence of dung beetles,” wrote Walters, “is a greater guardian of the organic red-meat supply than all the inspection certificates and agencies of verification can account for.”
Then there’s the comic sight of beetles flying to fresh dung as if directed by radar. “No one can say that dung beetles are good flyers,” wrote Walters. “When their encased wings are uncovered like some secret weapon in a military silo, they rise up almost helicopter style, then lumber along like an early Wright Brothers plane.”
Alas, industrial agriculture and its allies were not so amused. The news that their chemicals were killing critters deemed essential to the health of rangelands was not welcome. Infamously, Truman Fincher was forced into early retirement by the US government at the behest of Industry, according to Fincher himself. His research was put on hold and his laboratory samples destroyed.
The lowly dung beetle has struggled to regain its proper place in the ecosystem ever since. Fortunately, it’s making a comeback, thanks in part to rising interest in regenerative agriculture.
Hopefully, one day the scarab will return to its former lofty status!
To Learn More: Dung Beetles and a Cowman’s Profits by Charles Walters. Acres USA, Austin, TX, 2008.
Here is an informative TED talk on the dance of the dung beetle: https://www.ted.com/talks/marcus_byrne_the_dance_of_the_dung_beetle
My web site: www.awestthatworks.com
