I have a bad problem with what has been identified as a hister beetle. Also known as clown beetles? They are everywhere on my house like they’re trying to get inside. I also see them in our living room and kitchen. They are hanging around the ceiling and there is a bad smell like something died up there or is it the beetles? What can I spray to keep them from invading? I can’t take the smell and they just keep coming.
There are many types of hister beetles found worldwide; an estimated 4000 species or so exist with several hundred here in the United States. Most all are predaceous and feed on the larvae of other insects as well as eggs and pupae. They seemingly love ants, termites and maggots of any common house fly but will also eat dung, carrion and rotting fungi. Around the States the most common species we find around the home seem to target fly maggots and pine bark beetles. In fact, hister beetles are able to reveal valuable information used by CSI labs since certain species will arrive to a rotting carcass only when certain stages of decomposition have occurred. Based on their presence or absence, it can be deduced just what stage of decomp a body is at which can prove important for establishing a time line from the time of death.
Hister beetles will actively hunt prey during the spring, summer and fall. Common locations to find them are pine trees since they love pine bark beetles. Also known as engraver beetles, pine bark beetle larvae cause more damage to pine trees than any other pest. Hister beetles have been considered for biological control of this damaging pest but as of date there is no economically feasible way to utilize them. But it has been noted that homes surrounded by pine trees with pine beetle problems commonly find hister beetles too.
Hister beetles also love young and active maggots. They will sniff out decaying animals in their pursuit of fly larvae knowing that where something is rotting it’s highly likely some healthy maggot will be feeding. I suspect there could be a dead animal on or in your home which may indirectly be to blame for your beetle invasion. Hister beetles could very well be attracted to any decaying body and this would explain why they’re swarming your house seemingly wanting to get inside. You mentioned a bad smell; is there any chance you might have a dead rodent, bird or other animal in either a wall void, ceiling space or attic? If so, hister beetles in the neighborhood would no doubt smell it decaying. They would essentially be targeting the larvae (maggots) that are no doubt feeding on the carcass and for now, the ideal way to resolve the matter would be to try to track down the source of the smell. If you’re able to find a dead animal of some species, remove it and the histers will disappear as well.
But if you’re not able to find anything dead, there are some forms of treating that will help. For starters, you need to spray the outside of the home with BIFEN. This low odor product can be applied with a HOSE END SPRAYER and liberally sprayed on any side of the home you see them congregating. It will both kill and repel them so in the end, less will be able to enter your house.
Inside the living area, vacuum away any you find on the walls and ceiling. Hister beetles are quite tough and sturdy and will hide out of sight in any little crack you have along baseboards and ceiling molding. To insure they’re not avoiding people in these cracks, treat with PT-MICROCARE. This Pyrethrin based product will both flush and kill any that might be hiding and it will also provide a week or two of residual. This way you’ll have something in place to help protect the room from further histers getting inside.
You can also use the Bifen inside and it would be suggested if you locate an attic or crawl space that might be harboring a food supply for them. Spraying down the insulation and/or walls of the area will both prevent migrating maggots from living to pupate and kill off foraging histers. Again, the best solution will be the removal of the food source but if you can’t find one, treating the active areas with Microcare and Bifen will keep hister beetle numbers down.
Here are direct links to the information and products listed above: