Insects are a warm-weather nuisance to many. They damage gardeners’ plants, infiltrate households, and distribute general heebie-jeebies to the masses.
I could go on and on about the virtues of insects, how they are crucial to the ecosystem and more, but the fact remains that most people are relieved when bugs take a break in cold temperatures and leave us alone. But why do insects disappear in winter? Where do they go? When is the best time to contact home services such as pest control?
When temperatures plummet, many insects enter into a state of “diapause”. Diapause is defined as “an inactive state of arrested development”. Diapause is actually triggered by shorter daytime lengths in fall, rather than the cold temperatures themselves. But it is the cold temps that make the change necessary.
During Diapause, an insect’s metabolic rate drops to one-tenth or less of its normal rate. That way, it can use the insect’s stored body fat instead of fresh food to survive the winter. Insects can also produce alcohols in their bodies to use as antifreeze. This makes them able to “supercool” so their bodies can reach temperatures below freezing without icing over.
Different insects go through different life stages during winter. Some are in the egg state, while others may be in nymph, larvae, pupae, or adult phase. Most, though, spend the winter as eggs. If you look closely, you may be able to see insect eggs on branches or woody plant stems.
Some insects remain adults and use different techniques to stay warm throughout the winter. Some stay in shelters under fallen leaves or beneath loose tree bark. Others, such as lady bugs, live in herds under firewood or fallen tree bark.
Some insects, such as the Asian multicolored lady beetles, hole up in our houses until spring! It’s important to still keep up with pest control home services in winter for these reasons.
When warm weather beams in, diapause is relinquished. Insects reverse their “supercooling” capabilities and return to normal metabolic rates. Faster rates give them the energy needed to pursue food and reproduce before cold weather hits again.