Long-embattled, rare beetle offers hope of new discoveries to OSU researchers

• Beth Wallis
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Inside the basement of Oklahoma State University’s Insect Adventure, the room is stacked floor-to-ceiling with buzzing, flitting, scuttling life.

Inside these individual habitats live Jungle Nymph Walking Sticks bigger than the hands that hold them, African Emperor Scorpions with powerful pinchers and Striped Desert Millipedes with hypnotic yellow and brown rings. There are tarantulas, cockroaches and centipedes. 

But one insect in particular is getting special attention by OSU researchers: the American Burying Beetle (ABB).

This rare beetle, colored in black with rich orange spots, could hold the key to new medical treatments and novel meat preservation methods. But these beetles are facing threats that could wipe them out of Oklahoma — and perhaps most of the country. And some conservationists say the government hasn’t done enough to protect the dwindling population of ABBs.

The research

At OSU, three faculty members have begun to study the potential discoveries the ABB could hold: associate professor of entomology and plant pathology Wyatt Hoback, department head and professor John Gustafson of the Department of Biochemistry and Molecular Biology, and assistant professor of animal genomics Darren Hagen.

What makes the ABB unique is its ability to preserve food for its young. Male and female ABBs bury carcasses of small, dead animals, then remove the fur or feathers and coat it with anal and oral secretions. The female lays its eggs in a chamber next to the carcass, and once the eggs hatch, the young ABBs can feast on the preserved meat.

“And so our equivalent — if we have leftover Thanksgiving dinner and we dig a hole in the backyard, put it underground and come back in six weeks, it’s probably not going to pass the sniff test,” Hoback said. “Microbes are going to degrade the proteins in that carcass; the beetles need those proteins intact to feed their offspring.”

The beetles already provide a natural benefit for humans and other animals by contributing to fly reduction. When ABBs bury dead animals, they remove a breeding ground for flies, which can transmit pathogens. Hoback said the beetle is also good for the soil.

“They also increase soil fertility. It turns out that when a burying beetle buries a carcass, when it raises its offspring, it contributes nitrogen and phosphorus to the soil,” Hoback said. “And rangelands typically don’t get applications of fertilizer, so grazing by cattle eat vegetative material and strip nutrients from the land. These beetles actually add back nutrients to those soils.”

The researchers are studying the microbiome of the beetle — that is, the collection of microbes that live within or on an organism. They think organisms living in this microbiome could be responsible for reducing the rotting of meat from buried carcasses. 

Through gene sequencing, the researchers have also been able to identify several genes that seem to be turned on in the saliva secretions. 

For Hoback, the work is a continuation of more than 20 years of study and conservation efforts of the ABB. The beetle is recognized as a federally protected threatened species, which means the U.S. Fish and Wildlife Service (FWS) believes that while the beetle is not in imminent threat of extinction, it could be soon.

“We, as humans, are intelligent enough to see the value that organisms contribute and understand how we impact them, and therefore we’re ethically responsible for doing the best that we can do,” Hoback said.

The storied history of the American Burying Beetle

The ABB once lived in at least 35 states, but has since experienced about a 90% loss of its historical range. In 1989, the species was listed as endangered.

When the beetle was listed, it was believed they only inhabited parts of Oklahoma and Block Island — a small island in New Shoreham, Rhode Island. Over the next 20 years, additional surveys revealed beetle populations also living in Arkansas, Kansas, Nebraska, South Dakota and Texas, though no beetles have been documented in Texas since 2008. 

In 1991, the FWS released a recovery plan for the ABB specifying that to be considered recovered, the beetle would need to have 3 self-sustaining populations of 150 individuals in four regions. Though the ABB never met this benchmark, the FWS downlisted the beetle from endangered to threatened in 2020.

In the time between its initial listing and subsequent downlisting, the beetle became a center of controversy. In 2015, the Independent Petroleum Association of America (IPAA) petitioned FWS to delist the beetle, which would remove it from all Endangered Species Act protections. In the petition, the association writes about the costly and time-consuming hindrances to the oil and gas industry that the beetle has caused, such as delaying development of the Keystone XL Pipeline. One company reported spending $100,000 per beetle to relocate 119 of them.

With the petitioned interests of the oil and gas industry, as well as the Trump Administration’s efforts to weaken the Endangered Species Act, conservationists like Noah Greenwald, the endangered species director at the Center for Biological Diversity, said the decision to downlist the beetle was a politically motivated “gift to the oil and gas industry from the Trump administration.”

“The beetle didn’t stop oil drilling,” Greenwald said. “What it did is it required the oil and gas industry to mitigate the habitat destruction they were causing by putting money into a fund, which was then used to purchase conservation lands for the beetle. So this isn’t even about whether we’re about stopping economic development, it’s about the oil and gas industry not wanting to put money into a conservation fund for the beetle.”

The Center for Biological Diversity filed a lawsuit in March 2021 against FWS and the Department of the Interior, claiming the downlisting from endangered to threatened was unwarranted and calls for the reinstatement of the ABB’s endangered status. Greenwald argues because the Endangered Species Act defines endangered species as one at risk of extinction in “all or a significant portion of its range,” and because 90 percent of its historic range is gone, the beetle should still qualify. Greenwald also points out FWS has estimated beetle populations in the Southern Plains region will be wiped out in the next 20-50 years.

Other instances also contributed to the controversy of the downlisting. In 2013, two managers at FWS were found guilty of scientific misconduct by Scientific Integrity Review Panels after overriding experts to adopt an inaccurate map that shrank the range of the ABB, rushing the article to publication despite concerns and retaliating against scientists who spoke out against the publication.

In 2017, Hoback and another scientist, Douglas Leasure, were offered the opportunity to work with FWS to study how farming affects the ABB. Within about a month, the pair left the project, saying officials pressured them to combine maps showing the beetle population was wider-spread and safer than it actually was, and insisted the research be completed on a rushed timeline. Upon leaving, Hoback and Leasure had their names removed from the flawed analysis.

“It felt like the Fish and Wildlife Service wanted to conclude that agriculture is not a risk to the beetle and were going to use the data in a way that made that conclusion, no matter what,” Hoback told the Washington Post, which broke the story.

Despite the history of controversy, officials at FWS say the decision to downlist the beetle was not politically motivated, but instead was due to an entirely separate issue: climate change.

Climate change and conservation

Kevin Stubbs, a FWS biologist based in Tulsa, was working with the agency at the time of the downlisting. He said FWS had already started the assessment process for the beetle before the IPAA sent its petition, and the reason for the downlisting was mainly due to the predicted impact of climate change on the ABB.

Stubbs said instead of the original recovery plan, FWS used a Species Status Assessment. The agency looked at how resilient the beetle was under several threat scenarios and made its decision based on predicted resiliency, rather than a quota. The agency tested multiple climate scenarios and concluded that between 2040-2069, the Southern Plains populations will likely be wiped out. In the High Emissions scenario, all but the New England populations would die out by about 2070.

In the decision, FWS used what’s called a 4(d) rule. In this application of the rule, all intentional take — displacing, injuring or killing —of the beetle is prohibited. Incidental take is also prohibited, except in the Southern Plains region. There, outside of designated conservation areas, entities are exempted from incidental take prohibitions during activities not anticipated to injure or kill the beetles. The Southern Plains exception, Stubbs said, is due to the predicted reality of climate change.

“It wouldn’t matter if we protected all the habitat that was available down here if climate change was going to make that habitat unsuitable in the near future,” Stubbs said.

Stubbs said to be considered endangered, the beetle must be at a more imminent risk of extinction. The beetle’s “threatened” status acknowledges the risk of extinction, but only in the foreseeable future, instead of imminently. Stubbs said the FWS is not just waiting until the Southern Plains population dies out to reconsider the listing, and the agency conducts an evaluation of all species every five years.

One tool in the conservationist kit is the use of conservation banks. With a conservation bank, high quality habitat land is set aside, managed and protected with the goal of offsetting impacts of things like development from oil and gas companies or landowners. Entities wanting to use land inhabited by protected species purchase credits that pay for the land and its management.

Amy Smith, now the division manager for Apex Companies, worked with Common Ground Capital to set up and monitor conservation bank efforts. She said the numbers from their 2020 survey showed promise.

“I had a record number of American Burying Beetles at the American Burying Beetle Conservation Bank in the McAlister Conservation Area,” Smith said. “I handled over three hundred and fifty beetles in a five-day period.”

While the results of these conservation efforts offer a bit brighter outlook for the beetle, climate change is the issue many ABB conservationists are still trying to work around. Southern Plains conservation areas may not be usable for much longer if the beetles begin to succumb to climate change. Previous efforts to relocate Southern Plains beetles to Ohio were unsuccessful, and reintroduced populations have struggled with becoming self-sustaining, instead relying on managers to provide food for them. 

One reintroduced population at the Wah’Kon-Tah Prairie in Missouri has shown signs of promise, but it’s too early to tell if it will sustain itself in the future. The team of ecologists from the St. Louis Zoo are now shifting their efforts to a nearby Taberville Prairie Conservation Area, with the hope of creating a “metapopulation” of beetles. Bob Merz, the assistant director of the WildCare Institute at the zoo, said time will tell if the beetles will be able to thrive on their own someday.

“I think once we pull away and we stop putting beetles out, we’ll be able to assess if [these reintroduction efforts] work,” Merz said. “And that’s one of the hard things about conservation. … [It’s a] twenty, twenty-five year commitment sometimes before you even start to see results.”

In Rhode Island, Director of Conservation Programs Lou Perrotti has collaborated with several state agencies and other organizations to release thousands of beetles on Nantucket Island in the hopes of reestablishing a self-sustaining population. Perrotti has led the beetle’s captive breeding program at the Roger Williams Park Zoo since 1994, starting with beetles captured from one of its few remaining native areas, Block Island.

Perrotti said in addition to climate change, the ABB has been affected by habitat fragmentation and the loss or decline of major food sources, like the passenger pigeon and Carolina parakeet. He said he doesn’t agree with the FWS that the beetle’s downlisting was warranted.

“Anybody who’s a true conservationist and species biologist knows that the species is no better off today than it was,” Perrotti said. “We don’t even have one self-sustaining population in 28 years of efforts. … So that, to me, is truly still an endangered species.”

In Perrotti’s experience, the easiest animals to galvanize conservation support around have generally been the “cute” ones. 

“The cuter it is, the easier it is,” Perrotti said. “We can’t conserve species based on people’s fears and speculations about that species, because we’ll have a very fragmented ecosystem. So if we just save the bunnies and the butterflies, that’s not good either.”

That fragmented ecosystem could cause a catastrophic cascade of ecological effects, Perrotti said. He likes to look at nature through the metaphor of a bicycle.

“You’ve got a nice new bike. Every spoke in that wheel represents species on the planet. You might be able to poke a few spokes out and still ride the bike,” Perrotti said. “You poke one more out, it might wobble on you. You do more, it’s going to collapse. Every species plays an ecological role… And I think we owe it to those species to do the best we can to keep them on this planet and hopefully maintain the ecological role they play.”

Perrotti has worked with Hoback before on conservation efforts and said he sees promise in the researchers’ work studying beetle secretions. Though, he said it’s a sad reality that putting a human value on an animal makes people more likely to want to save it. 

“If we could prove that these secretions have a use for humans, whether it be battlefield necrotic wounds and keeping those from getting any worse, to coming up with a spray that’s against bacterial and fungal [growth] that could be used in meatpacking plants… I think it’s exciting, and I think it should be explored,” Perrotti said.

Hoback and the team of researchers see not only medicinal benefits from studying beetle secretions, but perhaps the work could spawn a renewed interest in conservation efforts for a storied beetle with a controversial protection status.

“So this beetle could hold the cure for cancer or the cure for food poisoning or the cure for whatever, right?” Hoback said. “And if we lose the beetle, then we also lose everything else that we could possibly discover. And that’s just irreplaceable.”

With the Center for Biological Diversity’s lawsuit and the potential benefits with new research, advocates and scientists hope the story of the American Burying Beetle is far from over. But the beetle, like so many other insects, will continue to battle the impending threat of climate change, and whether this brightly-colored bug will survive in Oklahoma much longer remains to be seen. 

Editor’s Note: This story has been corrected to change the spelling of Bob Merz’s name.