Haak raises beetle cleaning crew

Derek Haak, of Maurice, raises colonies of dermestid beetles to clean animal skulls like this elk head. The beetles do a more precise cleaning job than the traditional method of boiling bones, Haak said. [Click to enlarge]

Derek Haak, of Maurice, keeps live ones.

Thousands of them.

But the colonies of dermestid beetles Haak raises aren't just to look at. They've got a job -- a messy one.

The beetles clean off animal skulls and bones so hunters like Haak can preserve them.

"I had been cleaning my own deer skulls -- boiling them -- and that's kind of messy and not fun to do," Haak said. "I was thinking there must be a better way."

That's when he caught a TV program about dermestid beetles, also known as carpet beetles. The beetles are used by museums and taxidermists to clean meat and other tissue from bones.

Beetles work better than boiling because they preserve all the paper-thin nasal cavity bones, which are usually destroyed in boiling.

Haak's interest was piqued.

"Science was my favorite subject growing up," he said. "I've been pretty fascinated with the outdoors and anything to do with that."

Haak ordered dermestid beetles from a biological supply company he found on the Internet, starting out with 12 beetles and 12 larvae.

Now he has about 15,000 of the bugs at work for him.

To clean an animal skull, Haak removes the hide and fur then sets it in the container with a colony of dermestid beetles.

It takes about two to three days before they have cleaned the skull bone dry, Haak said.

All he has to do then is lift the skull out of the colony, shake it off and clean it with canned air.

"The largest thing we've ever done is a bison skull -- we're doing one right now -- they're about 2 1/2 feet wide. That takes a couple of weeks," Haak said.

Originally, Haak housed the beetle colony in a container in his garage in Maurice when he started more than one year ago.

The time it took to grow from just 12 beetles to a "hot colony" -- enough beetles to clean a specimen -- was about three months.

That's about 10,000 beetles, Haak said.

He decided he needed more space.

Haak had a friend in Rock Valley, Mike Bandstra, who was interested in helping him. Bandstra had access to a building in Sioux Center, so the two worked together to create a larger dermestid beetle operation.

They purchased box freezers that no longer worked, equipped them with ventilation and a thermostat attached to a heat lamp, and set up beetle colonies inside.

Walking inside the building, you can hear the beetles at work, Haak said.

"It sounds kind of like rustling leaves," he said.

Along with eating the tissue off the bone, the bugs are burrowing into styrofoam blocks, which is where they undergo the metamorphosis into adults, Haak said.

The growing beetles shed their exoskeleton eight times before they reach adult stage, he added.

While the beetles don't need any encouragement to do their work, they do need the right setting to live.

"You're constantly babysitting beetles," Haak said. "You need to make sure they always have something to eat and you need to keep the humidity about 50 percent."

Haak also needs to make sure other infestations don't get in with the beetle colony. He freezes each skull before he sets it in with the beetles to make sure no other species are inside.

Haak also makes sure he doesn't take any beetles home with him.

"They'd eat carpet, and they'd even burrow into wood," he said.

For now, Haak mostly cleans deer heads he brought back from hunting trips or other animal skulls for friends and family.

He has been known to trade a beetle cleaning job for permission to hunt on someone's land.

"Right now this is just a hobby," Haak said.

A growing hobby.

Haak is looking at buying another 10,000 beetles.

"We've got three more bison to do and a couple of elk," he said. "These are pretty neat little beetles."