A woman recently contacted us about a moth infestation she has been experiencing over the past couple of months, and she asks for our help in identifying and dealing with the problem. She has herself identified the moths as pantry moths (Indianmeal moths) “because they have a stripe across their body”, but is now wondering whether or not they could be drain moths.
The way this article is going to be laid out is detailing the context our reader provided, of which there is a lot (which we are thankful for), and responding to her questions and concerns. Unfortunately, as our reader did not send any photographs, we will not be able to make any identifications based on appearance, which does make it more difficult. She begins by asking us why she has been finding worms on her ceiling from pantry moths and how they got on the ceiling. She asks if the adult moth deposited its eggs “right there” or if it crawled there and “picked the middle of the ceiling to turn into a moth?” To answer all of these question, pantry moths lay their eggs in food (as in the food we humans eat), but once they are fully grown larvae and have eaten enough to sustain themselves through metamorphosis, they tend to crawl around the home in search of a dark, narrow and safe space to begin pupation. Hence, the worms got on the ceiling simply by crawling there! So yes, the larva did pick “the middle of the ceiling to turn into a moth.”
She also asks what the moth ate to reach that stage of life, because there is no food on her ceiling and all of her food in the kitchen has been stored in airtight containers for two months. Well, as we said, the larvae are not going to the ceiling in search of food, but to pupate. So, unless there really is food on our reader’s ceiling, as a result of some unhappy pancake-flipping incident, the pantry moth larvae will have found their food elsewhere. The fact that our reader has been storing her food in airtight containers is definitely the right move, and we commend her for it. Unfortunately, pantry moth larvae are sneaky little critters, and can find ways into one’s food regardless. For example, they could lay their eggs in the food taken out of the fridge, in dog/cat food, or even in birdseed!
Moving on, our reader tells us that she has been setting moth traps around her home every “night or morning” which are supposed to attract male moths using a “female scent.” She reports that she finds 2-3 moths “hanging upside down with their wings spread out over them” daily, and that in the last two months, the traps have caught “about 50 or more moths.” She then asks where those moths came from, as she has not seen that many moths “in [her] home since [she] started noticing them.” One possible answer to that question is that those are the moths that pupated on our reader’s ceiling. However, given the sheer number of moths she has found using the traps, this is unlikely. The pupation of an Indianmeal moth can last between 2-3 months. And so, while it would not be implausible to suggest that some of the worms she has been finding hatched in her food prior to her storing them in airtight containers, it is not likely that all of the moths in her traps were larvae in her food two months prior, as she would have noticed hordes of larvae in and around her home since then as they made their way toward the ceiling (and other places) to pupate.
Our reader then wonders if the moths are coming from outside her home and are attracted by her traps, which is definitely a possibility. We advise that our reader does check and ensure that any cracks and gaps are sealed — where possible — in her home, both in walls, flooring and window screens. Moths of all species could very well be simply flying in through an open window. That is especially likely now as it is getting warmer (depending on where in the world our reader is, of course) and people are leaving their windows and doors open more often.
Lastly, our reader adds that she thinks she has a leak in her bathroom as her floor has “gotten very soft and feels like it’s going to cave in.” She then asks if she has drain moths instead of pantry moths, and if they are coming in through the cracks in her floor and are likewise attracted to the moth traps. Although it is possible that a leak of some sort might attract drain moths (as they are attracted to moisture and are most commonly found in bathrooms), we are doubtful as to whether or not the moth trap would attract them. Of course, we do not know what moth trap our reader purchased and what species of moth it is supposed to attract, but nonetheless, the fact is that drain moths are not actually moths, but flies. In addition to that, our reader does describe seeing a stripe on the wings of the moths she has been catching, and while Indianmeal moths do have stripes, drain flies do not. Drain flies are a uniform gray/black and are fuzzy, while Indianmeal moths are beige/brown/black with one or more horizontal stripes of darker colors across their wings. That being said, it is possible that the moths are coming from cracks in our reader’s home. It is not uncommon for bugs to congregate inside the walls of older homes with weakening foundations. We know this is a creepy thought, but it is a possibility worth considering and worth fixing. We also recommend that our reader contact a professional to deal with her bathroom leak and floor as soon as possible, as the situation sounds quite dire!
To conclude, it sounds to us like the moth infestation our reader is experiencing could be made up of a variety of species of moths, but that the primary problem, which has worms crawling on her ceiling, is an infestation of pantry moths. Her moth traps may have backfired, attracting more moths than it eradicated. Seeing as her home now seems to be a hot spot of insect activity, and her bathroom seems moments away from caving in, we urge her to contact professionals to deal with both of these problems. We understand it may be difficult now during the pandemic, and our reader did mention that she is noticing these issues far more as she is staying inside, but emergency services should still be available in most locations nonetheless. Best of luck to our reader!