If you are dealing with pantry moths, you may think that, as the weather cools off, the moths are disappearing. Many people make the mistake of thinking that this means that the moths are gone, only to find that they have another full-blown infestation as soon as the weather warms up in the spring. The fact of the matter is that once the weather cools, the moths become lethargic, and the unhatched moths can go into somewhat of a "hibernation" phase- where they remain inactive and the process is slowed down enough that you will not be seeing adult moths during the cold months. That is why it is SO important to treat the moth infestation before the winter comes- or you will miss your chance to get rid of them, and they will STILL be hiding in and around your food (where you can accidentally be eating the larvae and eggs) until spring comes and they finally hatch into adult moths. It is imperative that you take action now to prevent the moths from settling in for the cold months.
To understand this hibernation phenomenon, we must go over the life cycle of the moth. There are four stages in this insect's life cycle:
1). EGG: These are very small- 0.5 mm- and cannot be seen by the naked eye. The eggs start hatching in 2-14 days (unless the weather is cold), usually beginning in April.
: This is the most destructive stage, and constitutes the majority of the insect's life. This stage can last from 2 weeks to a full year! In this stage- the moths look like tiny little white worms/ caterpillars. When they hatch from the eggs, they are very hungry and start feeding immediately. This is the only stage of the organism that feeds- so these are the buggers that are ruining your pantry staples. As they feed, they produce silk that loosely binds to food fragments, appearing like webbing or cobwebs that clump food together. This can be the first sign of an infestation.
The worms are capable of chewing through plastic bags & thin cardboard, and they can often be seen on ceilings and countertops. Mature larvae usually leave their food supply and wander about looking for a place to pupate (make cocoons). In heavy infestations, pupation may occur far from the original food source, which is why you can find the larvae in weird places throughout the home.
Temperature greatly affects the life cycle. Moths in areas with temperatures of 86 degrees & higher generally complete a life cycle in about half the time it takes moths in regions of or around 68 degrees F. Moths express lethargy in temperatures led than 50 degrees F. The larvae undergoes hibernation and metamorphosis inside a cocoon to avoid harsh climates & comes out as a moth for reproduction in the favorable time which is synchronized by a biological clock in the moths as well as ecological conditions prevailing there. During the fall and winter months, the larvae will often enter diapause (a form of hibernation) only to emerge as adults when the weather warms in the spring, and live out the remainder of their life in that general area.
: Upon reaching maturation, pantry moth larvae spin cocoons in the wall of their habitat, be it grain barrel or pantry. The chrysalis (pupation) takes four to 30 days.
Mature brown moths emerge from the cocoons and stay within the habitat of the larvae while searching for a mate. The sole purpose of the adult pantry moth is to mate and lay eggs, and they only live for 5-25 days. Females lay between 40-400 eggs on or adjacent to food. They usually fly in a zigzag pattern at dusk & through out the night.
It takes about a month to complete the whole life cycle, in the best of conditions, there can be 5-8 generations per year, and the hatching can overlap (which means that you could constantly have pantry moths in various stages for up to a year). This is why it is so important to interrupt their life cycle before you perpetuate a continual infestation. Being in the month of November- the moths are slowing down, and you are about to miss your chance at getting these pests before they hunker down for the winter. So, let's get busy and clean out the pantry! It is especially important to place any grains that you plan on storing long term in the freezer (to kill any eggs or larvae) and also to thoroughly wash down the delves, and storage areas like under the sink and where you keep the pots and pans as these can be prime real estate for hibernating/ pupating moths to hide out during the winter... biding their time until spring appears!