How insects survive the cold winter months
According to the Smithsonian, insects have different ways of surviving low temperatures during winter. It comes as no surprise as they are cold-blooded creatures. This means they are highly susceptible to such freezing temperatures because they don’t generate their own body heat. Whether it’s through long migration, freezing their own bodies, or even creating their own anti-freeze, insects have a variety of survival tactics during winter.
Insect Migration During Winter
The Monarch Butterfly, or the Wanderer, is probably one of the most widely known migratory insects in the world. According to the Australian Museum, Monarch Butterflies are found along the east coast of Australia and in southwest Western Australia, most especially during the summer. But come winter, when the temperature starts to drop, they leave the inland areas and journey towards the coast.
Apart from the Monarch Butterfly, Australian native budworm moths also migrate during the winter. These insects migrate a great distance in order to find the right winter food for their larvae. They are often found in breeding populations in inland Australia during the winter – a period considered to have good growth for their larvae to survive on. These are the same insects that feed on other plants, especially on your tomatoes. They know that winter means less food for them on the coast, so by the time temperatures drop in Autumn, they begin to move inland to stay there during winter.
Freeze Avoidance by Insects in Winter
Another way for insects to survive winter is by sheltering in place and entering an inactive state of arrested development. This may sound familiar as mammals also go through the same thing during winter called hibernation. When insects are in this stage, they start developing extra layers of fat to help them deal with low temperatures.
Besides, they also reduce their body’s water content. Water freezes quite easily versus other liquids, so reducing water and replacing it with glycerol helps them avoid freezing. One may have encountered glycerol before because this is like the anti-freeze that’s found in cars.
Freeze avoidant insects also remove food particles, dust particles, and bacteria in their gut to provide additional protection. They avoid these things because these are ice-nucleating agents, which means they form ice crystals. And ice crystals in their bodies are bad news.
Even though these insects prepare their bodies to avoid freezing during winter, taking shelter also helps protect them during this time. Where they take refuge is key to their survival and largely depends on their stage of development.
- Young Insects (Eggs, Pupae, and Larvae)
Young ones, i.e., eggs and pupae, can survive more at colder temperatures because they are in their non-feeding growth stage. Silkworms are one of the most popular pupae-wintering species around. One can find them attached to food plant branches during winter.
Insects that are in a larvae stage are protected against Winter by a cocoon. This is why one doesn’t usually see full-grown dragonflies or damselflies in certain parts of Australia during winter. They usually avoid the freezing weather by staying underwater as eggs or larvae.
Some young insects stay warm by covering themselves in leaf litter or a similar shelter. In the case of grubs, they go deeper into the soil and burrow themselves to get protected from the cold.
- Older Insects
Adult insects also find shelter and use antifreeze to protect themselves. Some of their favourite warm shelters are under loose tree barks, in tree cavities or even in unheated buildings. Basically, anywhere that they can fit their tiny bodies inside. Aside from looking for protection from the chilly winter winds, they must ensure that they are out of view of predators such as birds and squirrels.
Adult ladybugs and elder box bugs generally pick wall voids, attics, and other corners of the house and other structures as their spot for overwintering. This is also the case for wasps, flies, and even yellow jackets, which favour the eaves and attics of houses and barns during the winter.
- Social Insects
Insects known to thrive in communities like ants and termites stay in their underground colonies for the winter. They start storing food during the warmer months to sustain them through the cold winter. The same goes for bees which keep warm inside their hives during the winter. They also have honey and pollen stored inside their hive, which they have foraged on sunny days. The insects inside woody galls and borers in timber are also protected during winter, given their chosen habitats.
Freeze Tolerant Insects
On the other side of the spectrum are insects that prefer to be active during winter. This is the case for some insects like stoneflies. They spend the winter as nymphs, a stage that is close to being an adult. However, unlike other insects that are in arrested development, they actively feed and grow all winter long and become adults once spring comes.
There are also other insects that cannot not hide from the cold temperatures of winter, so they have no choice but to adapt. Insects that have high tolerance to the cold are more common in the Southern Hemisphere. They freeze some parts of their body to avoid the harmful effects of ice. But this kind of survival method must be done in specific ways and at certain times.
Yes, there may be fewer flying insects during winter since they may be hibernating or hiding away as pupae. But do not forget that these insects may return once the weather starts warming up. Remember that winter does not necessarily kill all the insects; it just slows them down.
Sydney Pet Inspections During Winter
It essential to continue routine maintenance inspections on your property during Winter. As it can help stop any pest infestation before it even becomes a problem. Inspections must be done by a reliable building inspection company like Exceptional Building Inspections. We can help you protect your investment. Call Robert Taylor today on 02 4950 4197 or 0412 188 199 for more information on our services.