Nature's Gravediggers

By Matt Seek | artwork by Dave Besenger | May 1, 2015
From Xplor: May/June 2015

This isn’t your typical love story. It’s about two beetles who meet on a starry summer night, hit it off, and settle down to raise a family. It’s a happy story really, but it isn’t for the faint of heart. It begins, you see, with an end.

Don’t worry about why the quail died — after all, our story isn’t about a bird. What matters is that just hours after the quail passed, a thumb-sized beetle arrived, appearing like a ghost from the darkness. It was an American burying beetle, and she had used her sensitive antennae to follow the whiff of death nearly two miles through the moonlight.

Dead Meat

Let’s get this tidbit out of the way: Burying beetles eat dead, rotting animals. Mouse-sized morsels are eaten on the spot. Larger corpses — like the quail in our tale — are used for something else.

Beetle Battle

When more than one beetle arrives at a corpse, they fight to see who claims it. Our story is no different. The female had just folded her wings when she heard the clicking and scraping of two male beetles locked in battle. The males pushed and shoved, their clawed legs kicking up tiny puffs of dust, until eventually — as is usually the case — the larger beetle won.

The Big Move

The beetles’ courtship was short, and they soon began working on a home for their future family. Unfortunately, the quail had died on a hard piece of ground and had to be moved. So, the beetles rolled onto their backs, wiggled underneath the carcass, and used their legs to push it forward. When one beetle slid the bird off its body, it ran to the front to take over for its partner. Millimeter by millimeter, the pair scooted the quail to softer soil. Burying beetles can move carcasses that weigh 200 times more than they do. To perform a similar feat, you’d have to lift a small school bus.

Race to the Grave

It now became a race against time. Night was patrolled by an army of thieves — raccoons, opossums, foxes, and coyotes. Sunrise would bring scavenging vultures and squadrons of flies. The longer the quail lay exposed, the greater the chance it would be snatched away. So the beetles did what burying beetles do best: They started digging.

Both beetles squeezed underneath the body and began using their flat, hard heads to loosen the soil and push it out from under the quail. Small rocks were thrust aside. Roots were chewed in two. Bit by bit the soil beneath the quail was bulldozed away, and inch by inch the quail sank into a shallow grave. On average, American burying beetles sink their carcasses about 9 inches underground. Some go-getters dig down a foot or farther. This is no easy feat. If you think it is, try burying a minivan in a single night using nothing except your hands.

With the quail safely underground, the beetles began snipping off its feathers, using their strong jaw muscles and sharp pincers. In short order, the quail was as bare as a plucked chicken.

Making a Meatball

Working together, the beetles rolled the quail into a tight ball. Then they coated the corpse with a gooey liquid from their mouths and backsides. The goo helped slow the decay of the carcass, keeping their meatball “fresh.” The female beetle scooped out a small chamber above the meatball and laid her eggs.

From Grave to Cradle

Four days later, 15 squiggly white grubs hatched. It’s rare for an insect to care for its young. It’s even rarer for both parents to pitch in. But burying beetles, as you might have guessed, aren’t ordinary insects.

Now you may want to hold off on that sandwich for this next part. Every so often, one of the adults would make a squeaky noise by rubbing its wing covers against its abdomen. This signaled to the babies that it was mealtime. To feed the hungry youngsters, the parents ate flesh from the meatball and then, like a mother bird feeding her chicks, regurgitated (threw up) into the waiting mouths of the babies.

Family life continued for about two weeks, until the quail was nothing but bones. Then, the adults tunneled out of the nursery and flew away. When frosts arrived, they would die. The babies burrowed farther into the soil. In late summer they would emerge as adults, snack on dead things for a few weeks, and then tunnel underground to spend winter. In spring the beetles would reappear to start a new chapter in the story of nature’s tiny gravediggers.

Even Beetles Need a Break

Our story had a happy ending, but the real outlook for burying beetles isn’t so rosy. A hundred years ago, American burying beetles were found in 35 states, including Missouri. Today, wild populations exist in only six, and Missouri isn’t one of them.

The Saint Louis Zoo, The Nature Conservancy, the U.S. Fish and Wildlife Service, and the Conservation Department are hoping to change that. Adult beetles reared at the zoo are being released at Wah’Kon- Tah Prairie, north of El Dorado Springs. Pairs of beetles, a male and female, are placed in holes containing a dead quail. Biologists cover the hole with soil and return in 10 days to see if babies were produced. The hope is that someday more than 1,000 of these interesting little gravediggers will live at Wah’Kon-Tah.


And More...

This Issue's Staff

Brett Dufur
Les Fortenberry
Karen Hudson
Regina Knauer
Angie Daly Morfeld
Noppadol Paothong
Marci Porter
Mark Raithel
Laura Scheuler
Matt Seek
David Stonner
Nichole LeClair Terrill
Stephanie Thurber
Cliff White