If you're a science student tasked with building an insect collection, flipping over a semi-decayed bit of road kill is bound to reveal a horde of dermestid beetles. Used by taxidermists and natural history museums, dermestids have been helpfully munching away at meat, muscle, skin and connective tissue for decades. The beetles clean bones in preparation for their future use as display pieces. Under these circumstances, a healthy colony of dermestid beetles is a good thing. But, when you find them under your carpet, they are not as welcome.
Establish a positive identification of the dermestid beetle. Capture a few in a jar and observe their physical characteristics. Generally speaking, dermestid beetles are mottled or dark or in colour, oval shape, less than ½-inch long and hairy looking. They are covered in scales known as setae.
Remove whatever is drawing them in. An infestation of dermestid beetles typically indicates the presence of an animal carcase in the immediate area, such as a dead mouse or bird. Opportunistic feeders, once the meat is gone they move on to a number of other natural food sources, making the most of whatever is nearby. Dermestids can be found living happily in bee hives or wasp nests or making a light lunch of fur coats, mounted trophy animals, or natural fibre carpets.
Locate the central areas of dermestid activity. These will be distinguished by an accumulation of skins shed by the growing larvae, unexplained holes in natural fibre fabrics, or an obvious build-up of fecal matter. Check in sheltered, out-of-the-way places such as basements, closest or the backs of drawers. Don't forget to inspect the underside of your home's rugs and carpets, as this is a favourite hiding place for dermestid beetles.
Take the main nozzle off your vacuum cleaner and use the hose to sweep up any visible beetles or beetle larvae. Then run the sweeper over any areas of discernible infestation. When you are finished, remove the bag from the vacuum and place it inside a plastic trash bag. Tie the top to seal and remove it from the house immediately.
Wash any affected rugs or fabrics in hot water at least twice, using strong soap and an additional laundry booster such as Borax each time. Dermestid eggs are well-protected and extremely durable due to their tough outer coating. The extra washings will help to ensure their destruction.
Borrow or rent a steam cleaner, if you don't own one, and diligently clean each and every bit of carpet in the house. Steam the furniture, too, if possible.
Sprinkle boric acid in any areas where dermestid beetles were previously discovered. Place moth balls or naphthalene flakes in closets or along the backs of cupboards. For a stronger approach, apply a commercial pesticide to cracks and crevices, around windows and doors, or directly on any large areas of infestation.
Boric acid has been known to have a bleaching effect when applied directly to fabrics which have subsequently become damp. Moth balls are toxic to animals and humans. Keep them away from kids and pets.