Have you ever thought that no single insect would survive through the nasty winter? Well you’ve thought wrong. We’ve suspected that all insects die during winter but this is not quite the case. Winter weather has little influence on the insect population that will come by in upcoming spring.
If we were to describe insects, they are a very pesky and versatile bunch. The reason why winter is not as impactful like most of us would think is because our pesky friends have found excellent means of surviving the harsh cold. We could think of them into two ways. There are insects who avoid the winter, and there are insects that are tolerant of the winter. Here are some ways insects and pests survive the cold season.
Insects who avoid the cold do not sit still in one place or area. They don’t wait to be exposed to cold conditions. Insects such as aphids, white flies and locusts have been known to migrate when seasons start to change. Their migratory patterns are different with some species travelling long distances and they usually migrate in big populations. Some insects also display the same behavior. For example, armyworms, earworms, and other Aphids reproduce in tropical and subtropical places.
Diapause, FROZEN BUGS!
The bitterly cold has not exterminated entire populations of insects. This is because insects that are more tolerant to the cold conditions have developed a number of ways to stay alive. In order to survive the winter, insects have developed a way of entering into a diapause stage.
Diapause by definition is a period of physiologically enforced dormancy between periods of activity. This means that there is a suspension of growth or development. It could occur at embryotic, larva, pupal or adult stage depending on the species. For some species it could be induced by environmental conditions. In others, diapause has become a mandatory part of their life cycle. During a diapause, insect metabolic rate slows down and their movement is limited in order to conserve heat. Some insects accumulate biological antifreeze in their cells prior to winter. Insects use specialized carbohydrates as biological antifreeze. These compounds lower the freezing point of the insect’s body fluids, preventing ice crystal formations inside the insect’s cells. If ice crystals form, the crystals would cause ruptures and tiny holes on their membranes. This would eventually cause death to the insect due to the cellular contents getting mixed up and disarrayed. With the lowering of freezing point of the insect’s bodily fluids, they are able to withstand temperatures below freezing point. This allows them to become frozen in the winter, and thawed out when spring comes. Some of these compounds are glycerol and mannitol, compounds that we are used to seeing in our everyday lives.
Laying eggs, Covering Up
Insects spend their winter in various stages of life: Egg, Nymph, Larvae, Pupae, or Adult. Many insects over the winter are still in their eggs. Many insects actually do die in the winter, leaving nothing but eggs behind. That means they are replaced by an entirely new generation in the spring.
Aphid laid their eggs on bud scales of woody plants. Bagworms lay on ornamental plants, and Mealybugs lay off egg masses on branches of trees. Other insects overwinter in the larval or immature stage. Turf-feeding grubs overwinter deep in the soil as beetle larvae. European corn borers survive as full grown larvae. Some insects improve chances of winter survival by building protective structures, such as cocoons or pupae, at a specific growth stage. This reduces surface moisture contact that could cause freezing. Insects such as coddling moths and swallow-tail butterflies overwinter as pupae in cocoons or chrysalis.
Hiding from the cold
Many insects brace the cold by hiding in different crevices and warm places found in our houses or trees. Others simply lay around the snow. Insects such as Curculio and bean leaf beetles spend their winter as adults in protected areas, such as under loose tree bark and in fallen leaves. Native Lady Bugs overwinter in herds under fallen tree bark or firewood. Asian multi-coloured lady beetles look for a warm spot in our homes to wait for spring. They seek out a protected spot and lay dormant until the winter season ends.
Some insects use geothermal heat to keep them from freezing. Insects like Japanese beetles, June bugs, cut worms, fire ants and dung beetles do not leave. They instead avoid freezing temperatures by burrowing themselves in to the ground.
Insects continue the next life phase on the spring time. The warmer temperature of spring serves as a wake up call for those who are in the diapause stages of their lives. They generally do not come out as early as this may cause them their demise. However, they tend to wait out a bit until they are sure temperatures will not revert back to a colder environment. Insects are highly adaptive creatures, but winter conditions can affect their survival. Temperature fluctuations, the duration of the cold season, snow cover and the environment during the season all play roles in their survival.
The best predictor of insect survival will be the conditions when the insects re-emerge from their slumber or hatch. Insects need food when reaching spring time. These little critters are famished and they need energy. They need food.
Sometimes weather delays growing crops and vegetables. This delay is deadly for some of the emerging insects since they rely on the crops for food. This reduces the population due to the limited food supply present. However during spring time, these critters will be lurking around your gardens and homes. They would be very pesky. Expect your garden to be riddled with such pests.
Insects have different ways of getting through the cold winter. Best be prepared by disinfecting your garden once the spring time comes. Eliminate the homes of the pests and pull out any weak plants you see lying around. Keep you foliage dry most of the day and build healthy and organic soil. Follow these tips to keep those pests away.