Instead, ants frequently come inside during heavy rain because they, like people, prefer a secure, dry place to reside. When the rains come down hard, you may anticipate ants to enter your home through every opening possible—cracks in windows, gaps in brickwork, or doors that don't seal completely shut, to name a few. However, most ants will only invade when the temperature is at or near their tolerance level. If it's cold outside, they'll seek out warmer shelter inside. If it's hot outside, they'll search for cooler places to live.
Ants are very efficient at finding new ways into houses. They need food and water, so they tend to find these things where they can. This often includes breaking into homes through small openings such as cracks in windows or doors. Once inside, an ant will try to establish itself by forming a colony in a safe spot. This might be under a sink, in a cupboard, or on a wall. From there, it creates more tunnels and bridges over other objects until it has reached more important areas of the house such as the kitchen or bathroom. Only then does it begin to build its nest and look for food and water.
Ants are responsible for spreading several diseases, so it's important to keep them out of the house.
You've certainly observed that ants come indoors more frequently in the summer—this is partly due to the fact that most insects are more busy during the warmer months. Ants will occasionally venture inside in quest of water, especially during dry spells. In this situation, they may be found in bathrooms or other humid areas of the house.
Ants also come indoors to escape the heat outside. As the temperature rises, so does the rate at which ant bodies decompose. The smell is what makes humans want to get away from it, not the nature of the insect itself. If you find an ant on you when it's hot out, don't panic! It's not a sign of a serious problem with your home health system.
In addition to being brought in through doorways and window openings, ants can enter houses via underground tunnels or bridges. These structures are often built by worker ants in search of new homes. When they find one, they return to their original colony and tell other workers where they're going. Then all parties involved excavate a tunnel or bridge to the new location.
During warm weather, ants will often abandon their colonies and look for new ones. The purpose of swarming is to establish new colonies with better food sources and lower temperatures. It's thought that ants sense when it's time to swarm based on the number of eggs in their nests.
Ants are most likely to enter homes in cold, wet circumstances, such as those found in Northern California during the winter, they write, noting that a lesser peak in the degree of infestation occurs during hot, dry conditions, such as those found in August and September. They say that this makes sense because when it's cool and damp outside, ants will want to keep their temperatures down by seeking out ways to warm up their environment, which means more trips into houses looking for heating ducts and other sources of warmth.
They also say that when it's hot outside, there will be less need for ants to travel far from their colonies to find food, so they'll be more likely to spend their time searching out houses to invade. When you combine these two factors, it seems like there should be more ant activity in summer than in winter or spring.
But don't just take my word for it. There are some studies out there that back up what we're saying! One study conducted by UC Berkeley looked at how often ants entered houses throughout the year, and they found that although there's generally more ant activity in the warmer months, there is also more activity in the colder months too!