El Dorado Springs, Mo. – The American burying beetle is a large and unusual insect. The parents tend young in an underground cavity, and they feed on carrion such as dead birds. Habitat losses or changes have made them an endangered species. But a cooperative restoration program between the Saint Louis Zoo, the Missouri Department of Conservation (MDC), and the U.S. Fish and Wildlife Service (USFWS) has re-established a population at the Wah’Kon-Tah Prairie and Taberville Prairie conservation areas in St. Clair County.
The zoo staff raises American burying beetles and releases them in early summer in a partnership with MDC. The Nature Conservancy of Missouri owns large sections of Wah’Kon-Tah Prairie, which is managed by MDC. The Taberville Prairie Conservation Area is owned by MDC. Both prairies are part of the Upper Osage Grasslands, an MDC priority geography devoted to enhancing native grassland ecology on both public and private land.
Releases began in 2012. A pair of male and female beetles are placed in a hole with a dead, pen-raised quail and covered with soil. That mimics the beetle’s natural reproduction cycle where they pair up, then drag some type of small dead bird or mammal to a site. The beetles dig a hole where they stay until young have hatched from eggs. They feed the larvae from the carrion they stashed. Adults later emerge to wander the prairies or woodlands.
A release of more zoo-raised burying beetles this year was almost scuttled by precautions against the COVID-19 virus. But Bob Merz, assistant director of the Saint Louis Zoo WildCare Institute, led a small party following safety precautions. They released 77 beetles on June 15 at Taberville Prairie Conservation Area. Concerns about coronavirus have so far cancelled this year’s survey for beetle populations originating from releases in past years. But earlier surveys showed promising results.
“I feel that we have given the beetles the best opportunity to thrive as we possibly could have,” Merz said. “We set them up to succeed. Seven years of reintroduction and supplementing with carrion resources that they raise their young on was done in a way where we saw that the species could meet important benchmarks. They survived winters in decent numbers, and we saw evidence that they were finding food and reproducing on their own for all of those years.”
The first releases were at Wah’Kon-Tah Prairie. But no more releases are planned at that prairie. The zoo, MDC staff, and biologists for the USFWS are now monitoring the burying beetles at Wah’Kon-Tah to see if they can now sustain their population without new releases.
“Their numbers were good, so I feel really good,” Merz said of past surveys. “However, the proof of the pudding for this species is if they survive without our help now. That, only time will tell.”
The American burying beetles released at the two prairies are considered a non-essential population by the USFWS under federal endangered species protocols. That’s because they were raised at the zoo, rather than a surviving historic wild population. The non-essential designation means that there are no restrictions placed on land uses. Any farms and ranches in the release area can operate as normal.
For more information about the American burying beetle program at the Saint Louis Zoo, visit https://short.mdc.mo.gov/Z84. To learn more about MDC’s partnership with the zoo, visit https://short.mdc.mo.gov/Z8o.