Tuesday, June 07, 2011

Small, Brown, Hardshell Bugs!

Have you ever found small, brown, slow-moving bugs crawling around your house that appear to have a hard-shell? If you look closely the hard cover appears to be split down the back. These are probably one of several "stored product" beetles that infest dry foods and natural fabrics. If the beetles appear black, or mottled with red/gray/black, instead of brown they are probably one of the dermestid (Dermestidae) carpet beetles but the brown ones are likely one of the anobiid (Anobiidae) beetles, for example the cigarette or drugstore beetles.

If the brown/black beetle has a tan stripe across the back it is probably the larder beetle, another one of the dermestid beetles.

This very large and diverse group of beetles are specialist scavengers on dead plant and animal products. They evolved as nature's master recyclers that help breakdown and decompose dead plant and animal tissue. If you think about it from the beetle's point of view a piece of wool cloth (or animal carrion) or a dog biscuit (or cache of seeds) is just another dead animal or plant, and something good to eat.

Larval Stage
The larvae of all these different beetles are the real recycling workhorses whereas the adults are simply there to ensure the next generation. Depending on the species, larvae can survive on a wide range or natural plant and animal matter, from cereal stored in cupboard to the wool rug in the den. In more natural situations they would feast on dead plant material or animal carcasses.

When you find the beetles indoors it usually means there's an infestation somewhere in the house. The beetles are harmless but obviously if the infestation is large damage can be done to your stored food or natural fabrics.

See the pages cited above for ways to detect and manage infestations of stored product beetles. Once the infestation is found and cleaned up you can treat the surrounding area with one of the new Botanical Insecticides to eliminate any stragglers that may have been missed.

3 comments:

Kristi Watson said...

Thanks! This sounds exactly like what we have, but we can't figure out where they came from. I was glad to find out they eat dead stuff instead of me. I especially liked your comment from the beetle's point of view. It made me laugh when I was all creeped out over these minute creepy crawlies.

suga said...

I've been plagued by these rust colored beetles with relatively shiny and hard shells. They seem to be getting into all dry foodstuffs, and also seem to enjoy things like chocolate bars! If, however a piece of fruit or carrot stick is left on the table, they'll soon he on it. They grow between two to four mm in length, and seem to enjoy laying (not eating) on white paper towels. I've thrown out thousands of dollars in wasted food, and am at my wits end! What can I do to finally iradicate them, and how can I store food in the future? I use large amounts pasta, and don't know how I can keep them from being pillaged! If we were ever in a crisis situation, I feel like any attempt at food storage would be in vain!

Natale Fish said...

Suga, I would recommend investing in a large quantity of air-tight Rubbermaid/tupperware containers to store your dry goods. I used to live in apartment buildings which were 150+years old and had to do that to keep mice away. I had a great mouser cat, but she couldn't keep up with them since there were exposed pipes which the rodents used as highways around the building. Grosssssss! But, I found the tupperware kept my cereal, pasta, flour, rice etc safe from any kind of bugs as well as mice.
Good luck!!
~Natale