They Can Feed on What?! (AKA: Procrastinating my talks)
I’m headed to the Georgia pest control conference this week and I have two presentations to give on fumigation. So naturally, I’m procrastinating and I got off on a tangent when someone asked me about cigarette beetles. Cigarette beetles are really fascinating from a scientific perspective and a real pain from a pest control perspective. As I was running down my current procrastination rabbit hole, I came across some great stuff.
Insect light traps are pretty effective at attracting these beetles. Even in the presence of food (typically a strong attractant), the adults are attracted to ILTs and it’s the UV output that’s attracting them. Interestingly, unmated males are the most attracted followed by mated females. While ILTs can’t be used as a control method, it’s good to know that they are taking some of the adults out of the equation.
These beetles are pretty sensitive to temperature, but still pretty hardy. Their ideal temp appears to be between 30-33C (86-91F), and they will reproduce the fastest and live the longest in that range. However, it doesn’t mean they won’t survive (and procreate!) at temps outside those ranges so using heat or cold as a treatment method still means some pretty extreme temps. The egg stage is the hardest to kill with heat and needs more than 10 hours at 50C (122F). The pupal stage might be the most cold resistant: pupae held at -10C (14F) for 24 hours had a few adults successfully emerge!
Think you can suffocate them? It takes eight days at 0.1% oxygen (remainder nitrogen) for complete mortality of the eggs.
Cigarette beetles have been around for as long as we have been storing food. The beetles have been found in sealed Egyptian tombs, likely feeding on the grains and spices that were interred with the deceased…though they could be feeding on the bodies as well.
Cigarette beetles are notorious for getting into spices. A study from India showed over 60% loss to fennel seeds after seven months of storage (however, there was no information on how the seeds were stored). Some other odd items cigarette beetles can develop on: cumin seeds, chamomile flowers, roselle flowers, fenugreek, and turmeric. I’ve also personally observed them feeding on cayenne powder! They are actually ATTRACTED to chili powder!
As the name suggests, cigarette beetles feed on tobacco and can be a big issue in cigarette and cigar manufacturing. They are also a problem in cannabis operations, particularly the seeds.
This might be my favorite example of odd food material:
We were alarmed in January 2010 when small (2.4 mm), brown beetles, later identified as Lasioderma serricorne (F., 1792) (Anobiidae) (Fig. 1), began to appear on the floor of the insect collection room at the Smithsonian Tropical Research Institute (STRI) in Balboa, Ancon, Panama City, Panama. There were too many beetles for them to have entered the room one by one from outdoors, yet none of the specimen drawers had infestations. So from where were the beetles coming? The search lead to a large bag of packing peanuts accumulated from parcels received from other museums, and now stored, ready for re-use when we send specimens out. The bag contained mostly polystyrene peanuts, but mixed in were a few starch-based biodegradable peanuts; the beetles were associated with the starchbased peanuts.
Speaking of odd food sources, cigarette beetles are often found in museums. Think of all the old plant material, animal material, and more that is available for these insects to feed on.
The moral of this story is that cigarette beetles are incredibly hardy little buggers and will feed on a wide range of things we may not think of as traditional “food”. They are hard to detect and can do quite a bit of damage. If you have been having issues with cigarette beetles or any other stored product pest, contact us, we can help look at your pest management program and provide solutions. Now I really should get back to doing my fumigation presentations (oh look, a video on cigarette beetles!). Wish me luck at my conference ... or as I’m calling it: the pest control super spreader event. (Who holds an in-person conference at the current massive peak of covid cases with NO maks requirement?!?!)
Lagniappe - this