Working Together to Save American Burying Beetles

Posted June 9, 2022 by Mandy Pritchard

Mandy Pritchard, Team Leader at the Cincinnati Zoo’s World of the Insect is currently out in the eastern Sandhills of Nebraska with Cincinnati Zoo World of the Insect keeper April Pitman and colleagues from The Wilds and Nebraska Game and Parks. They are working together to collect threatened American burying beetles (ABB) and release their offspring back to the wild in Ohio.

The ABB was once found everywhere in the eastern United States but because of a handful of issues (habitat destruction, increased scavenger populations, etc.) they are now only found in a few counties in a few states like in the eastern Sandhills of Nebraska!

Here’s a look at Mandy’s trip out West to help save this species:

In the eastern Sandhills of Nebraska is a population of American burying beetle (ABB), a federally threatened species that have been extirpated from over 90% of its historic range.

World of the Insect keepers from the Cincinnati Zoo have been working to reintroduce this species to Ohio since 2012.

Our keepers along with colleagues from The Wilds and Nebraska Game & Parks headed to the Sandhills this week to collect some beetles to support reintroduction efforts in Ohio.

To catch the beetles, we use simple pitfall traps baited with carrion. ABBs are nature’s undertakers and literally bury small animal carcasses which they use to raise their young.

Once we sink the trap into the ground, we put a cover on top to protect the beetles from rain or sun. We put soil on top to help hold it in place.

The next morning we come back and check the traps to see what we caught!

We pull out all the insects that fell into the trap overnight, keeping any ABBs and releasing any other species.

This year the efforts were really successful and the team caught 264 ABBs total!

The team records locations, number of beetles, weights, and measurements of the individual beetles every year. That information helps scientists with Nebraska Game & Parks and USFWS keep an eye on the population over time to help guide decisions regarding this threatened species.

Once the beetles are weighed and measured, the majority of them are released. The team kept 30 males and 30 females who were set up in individual containers with all their relevant data. The keepers will drive these ABBs back to Ohio to breed in managed care to produce a reintroduction population for 2023!

Part 2: The Release

The 60 ABBs brought back from Nebraska this summer were extremely prolific and produced about 1100 offspring! That’s about 500 more than we were expecting so we needed to call in some backup.

Introducing the Beetle-mania team! Zoo Teens, volunteers and all of the insect keepers stepped in to help. Our uniform included matching antenna so all the new beetles would feel at home.

Two months after the parents were bred at our facility their babies emerged as adult beetles and the processing began. First we sift through the soil from their breeding enclosures to find any stragglers that didn’t emerge on their own. Next we had to separate males and females which is thankfully very easy since they have different markings on their heads. Then we needed to weigh and measure each beetle and adhere a unique ID tag. Weighing and measuring helps determine who will be bred together for the next cycle and who will get released. The ID tags help us keep track of everyone since they are housed in same-sex sibling groups. Inbreeding needs to be avoided at all costs so it’s important to carefully keep track of each individual beetle. As you can imagine this entire process takes a lot of time and a lot of patience.

When we realized how many offspring there would be this season we got permission from ODNR and the USFWS to release a large group of them in late summer once they were processed. There’s no possible way we could breed all 1100 beetles at the zoo this winter so we wanted to put them out in the wild as soon as possible to give them the best chance at overwintering in Ohio. So after processing everyone, we released almost 400 ABBs at The Wilds, our partner organization. Those beetles will be free to roam The Wilds, overwinter below the frost line, and hopefully reproduce on their own!

We carried the 400 beetles into a forested area with lots of shade to begin releasing them. At this time of year the beetles aren’t interested in reproducing, but rather are trying to find lots of other bugs to eat so they have enough energy to make it through the winter.

ABBs are nocturnal and high temperatures can actually harm them. When we release them into the wild like this we poke small holes in the cool soil and “plant” the beetles in those holes so they don’t overheat in the sun. The beetles can then decide when they want to come out of the soil and fly off to find food. Next spring the keepers and field technicians from The Wilds will set out live traps to see if any ABBs from this release are still on grounds!

The remaining 700 ABBs that weren’t released were split between the Cincinnati Zoo and The Wilds for breeding. Stay tuned to see how breeding goes this winter and how many beetles we will have to release in the summer of 2023!

Watch more here:

@cincinnatizoo Bringing American burying beetles back to Ohio! #conservation #cincinnatizoo ♬ original sound – Cincinnati Zoo