EL DORADO SPRINGS, Mo. -- Insects are unique to start with. But the American burying beetles take evolutionary traits a step further. This federally endangered beetle feeds and cares for its young, unlike most insects, and the bug parents possess some unique skills when it comes to turning dead animals into dinner.
Entomologists have not found this carrion feeder on a Missouri native prairie remnant since the 1970s. But the Saint Louis Zoo, in partnership with the Missouri Department of Conservation (MDC), will release about 150 pairs of American burying beetles on June 5 at the Wah-Kon-Tah Prairie north of El Dorado Springs. Also partnering in the project is The Nature Conservancy of Missouri and the U.S. Fish and Wildlife Service.
Since this is classified as a non-essential experimental release by federal authorities, the burying beetle’s presence will not affect property owners in the area despite its status as an endangered species. The only prohibition is capturing and selling the beetles. It is now found in only a handful of states.
The beetle’s unusual life patterns will require a unique approach for their release at Wah-Kon-Tah, said Bob Merz, director of the zoo’s restoration program for burying beetles. The zoo is funding all costs for the release and restoration program.
Returning the beetles to grasslands could be important to prairie ecology. Less than one half of one percent of Missouri’s prairies remain, and this effort returns a colorful insect that may serve important purposes.
“This was a useful species that used to be common in 35 states,” Merz said. “It was found here in Missouri well into my lifetime, but now it’s not here. Something is going on out there that impacts a species, a species that may or may not be an integral part of the ecosystem.”
Burying beetles scavenge dead animals. The adult beetles have black and orange markings and can be an inch and a half long. Working in pairs, they can lie on their backs and push up with their legs to move a dead bird or a chunk of flesh from a larger carcass to a spot where they want to lay eggs underground, Merz said. They will then dig a hole and bury the food, and they use secretions to firm soil around the food to form an underground chamber. Here they will mate, the female will lay eggs, and they will care for the young larvae.
The beetles strip meat from whatever carrion they’ve scavenged. They remove bones, fur or feathers and create a “meatball” that is preserved by secretions that inhibit bacteria and fungus. After the young hatch into larvae, looking like tiny grub worms, the adults use their wings to make a sound that calls the young to meals. The parents feed the young from the meatball.
Merz and staff will be digging holes to bury burying beetles for the release. Circular holes will be dug that are paper plate size in diameter and about nine inches deep. The sod will be removed as a plug and set aside. Then crews will dig another hole or chamber in the side. They will place a dead pen-raised quail and a pair of beetles in the chamber and replace the sod plug in the hole.
Crews from the zoo will check some holes this summer to see if young were produced. By late July or August, biologists hope new burying beetles will have hatched, gone through the larvae and pupae stage, emerged as adults and be looking for food on the prairie. They are nocturnal and spend most of their life underground.
The beetles to be released were propagated at the zoo. Zoo staff collected the founding generation at Fort Chafee, Ark.
Merz began studying the burying beetles a decade ago. The zoo’s breeding program began in 2004. This is the zoo’s first release of the American burying beetles at a Missouri site. For more information visit http://www.stlzoo.org/conservation/wildcare-institute/americanburyingbeetleconse/.
For more information on Wah-Kon-Tah Prairie, go to http://bit.ly/Kgj3Bt.