Meet the beetles! These rice-sized workers clean up specimens at Seattle's Burke Museum

Listen to the sound of the Burke Museum's secret clean-up crew by playing the audio clip below. (Courtesy of Daniel Peterson)

Meet the secret workforce of the Burke Museum

Very few museum visitors realize that thousands of secret workers are helping make these specimens. No, it’s not a secret organization of janitors. But this team also cleans up expertly.

The secret workforce cleaning up specimens is a team of flesh-eating beetles better known as dermestid beetles.

Dermestid beetles — only the size of a grain of rice — perform a crucial task that humans cannot replicate: meticulously clean decaying animal remains down to pristine animal bone specimens.

These beetles are part of a global clean-up crew called decomposers, organisms that work tirelessly at the beach, desert, the arctic, all over. Decomposers turn decaying remains into nutrients that jump start the cycle all over again.

But at natural history museums like the Burke, scientists intervene in the decomposition. Otherwise the beetles will eat the bones. They’ll eat everything, really.

“Anything that used to be alive is fair game,” said Jeff Bradley, a mammalogist and collections manager at the Burke Museum.

Feathers, fur, guts, bone — all of it can be slurped up by these voracious beetles.

An up close view of the Burke Museum's beetle lunch room. On the menu: a river otter.

KUOW Photo/Paige Browning

“It is super crucial that none of these hungry beetles get inside and get access to our collections.”

Containment is key for this museum, especially for people like Bradley who frequently work with the beetles on potential specimens.

You can think of Bradley’s job as a collection manager as being the museum’s librarian. Except instead of books, he manages a collection of 55,000 mammal specimens.

Getting to the beetles is like working your way through a maze of the museum. You go past the mammalogy department — where Bradley works — and through the bird team's hub, down past the fluid lab, then down the stairs and out the doors past business support. And then you have to leave the main museum completely and head for the parking lot.

Just a few paces away, the beetles crackle and rustle as they consume their latest meal. Bradley brings a rotating menu of carcasses every few weeks to the beetle room.

On the menu you won’t find any top-ranking dishes from KUOW’s Seattle Eats. Instead you’ll find the decaying remains of pelicans, river otters, and wolverines.

These beetles have strict dining and working conditions:

• The room must stay cold.

“ We don't want them to get too warm in there, because they'll also fly when they get warm, and that would thwart a lot of our containment methods,” Bradley said.

• The room must be dark.

“ They don't like light — they will run from the light,” Bradley said as he lifted the lid off the box.

The beetles eat and eat and eat until they poop. Or until they produce frass, insect excrement.

Dermestid beetles have a built-in dissolver in their mouths that they use to process decaying animals and turn them into nutrients. These dissolvers are called enzymes.

Yes, people have enzymes, too. But these beetles have enzymes that can quickly break down and digest hair, feathers, shells, and skins thanks to their unique enzymes.

“ There are other ways to get these (carcasses) cleaned,” Bradley said. “We could use chemicals or we could just soak them in water until the bacteria took care of everything. But the beetles are much more efficient and they do a better job in terms of the skeletons come out cleaner at the end.”

And with each chomp, they dissolve tough parts essentially blasting them into a frass smoothie. Every decomposer plays a distinct role and these funk-producing beetles specialize in processing harder stuff – things other decomposers might have a hard time eating.

The thought of being in a room full of rotted flesh and boxes of carcasses doesn’t exactly bring you to the water. But for his part, Bradley sees the beetles in their best light.

“You gotta think what would happen to all those dead carcasses in the woods … if we did not have decomposers to take care of them,” Bradley said. “There'd be a lot of dead animals laying all over the place. That wouldn't be good."

In fact, that could throw the whole ecosystem out of whack.

“So it's important to embrace the good aspects of things [for which] maybe your first impression of them isn't so good,” Bradley added.

One carcass working its way through the beetle colony at the Burke tells a unique story about wolverine survival. This specimen, a wolverine kit, was found near Mt. Rainier in Washington.

Dermestid beetles helped clean the skull of this wolverine kit.

KUOW Photo/Brandi Fullwood

Wolverines are rare in Washington. There are only a handful of them left. In 2020, a mother wolverine gave birth to a few kits. This was the first time in 100 years that wolverines were born in the park. The mammal team at the Burke said this male kit is likely one of them.

“ So we need to study it,” Bradley said.” We need to find out what went wrong.”

After the beetles do their job, researchers will be one step closer to understanding this wolverine specimen's story. And it might tell us about the resilience of rare baby wolverines.

How are you thinking about the idea of breaking things down? Tell us what you've seen be broken down and turned into something new and amazing by shooting us an email at spectacular@kuow.org.