Insects have a variety of strategies for bad weather, including hiding from the downpour, dodging and deflecting the drops, or even using the bad weather to their advantage!
In the midst of a hot and sticky summer, a good thunderstorm is always welcome, bringing much-needed relief from the sweltering heat, as well as from the swarming bugs—or so you hope! Humans react to precipitation in a number of ways—umbrellas, waterproof clothing, and staying indoors/under cover, but most other creatures on the planet don’t have those sort of luxuries. In particular, there are hundreds of billions of insects on this planet, many of which are used to flying through the air, that must occasionally deal with falling droplets of death from above!
So… how do insects handle rainy weather? Where do flies and bugs go during storms?
Unique Challenges of Insects
Being tiny, agile and able to fly are the normal advantages of insects, but in the case of inclement weather, such as a storm or cold weather, those same characteristics don’t reap the same rewards. Insects are ectothermic, meaning that the temperature of their small bodies reacts to the outside surroundings; when the weather is cold, the metabolism of insects slows down, as do their activity levels; on the other hand, in warm temperatures, insects are energized and highly active.
When an insect is wet, they also take on additional weight, which can make it difficult to fly. Water can also cause their wings to stick together, in some cases. Combined with lower energy levels, in the case of damp or cold weather, this can make insects vulnerable, and decidedly less agile. High winds that are often present during storms will also make it more energetically expensive to fly and remain on track. The strong exoskeleton of most insects will allow them to be buffeted into objects without any critical damage, but it is probably an exhausting process. Finally, raindrops fall with an average speed of 10 mph, and would generate a huge amount of impact in comparison to the weight of most bugs, which could be potentially deadly.
Taking Cover vs Taking Advantage
Given the risks involved in the case of wind and rain, many insects do the logical thing and seek shelter. A multitude of species have shown a sensitivity to changes in air pressure, allowing them to predict when rain or bad weather is going to strike. In anticipation of this, they can find shelter, by burrowing into logs or underground, or taking a respite underneath leaves, undergrowth, rocks or the eaves of buildings. Generally, getting out of the sky and underneath some type of cover is the go-to response for bugs.
However, this isn’t the case for all bugs, as some are better equipped to withstand the harsh winds and violent impacts from raindrops. Larger bugs, e.g., beetles and dragonflies, are hardier and more capable of withstanding the impact of raindrops, and have greater control over their flight patterns in the wind.
Annoyingly, mosquitoes also seem uniquely capable of surviving downpours of rain, despite their minuscule size and weight. Research has shown that mosquitoes don’t actually slow the impact of raindrops considerably, and therefore take less of an impact from the raindrop. Rather than resisting the impact, a mosquito will “ride the wave”, so to speak, and may plummet a few dozen feet before escaping out from beneath the raindrop. Uniquely water-resistant hairs all over the insect’s body repels the water, allowing the mosquito to slide out from under the drop and continue on its flight towards the nearest blood-filled creature.
While being constantly bombarded and plunged towards the ground may seem frustrating, with so many other bugs hiding or biding their time, mosquitoes can take advantage of a cleared playing field in their search for food. Other bugs also use rain as an indicator that it is time to mate; once spring rains have slowed or stopped, certain species of leafcutter ants will release pheromones to pull in a mate; males will also emerge from the ground after the rain and be drawn towards the scent!
A Final Word
Most humans try to avoid walking around in the rain, though there are those who truly enjoy it, and make the most of the downpour. Similarly, most insects will try to seek cover and avoid getting wet or cold until the rains pass, but there are certain species who revel in the advantage (and potential mating) that a good rainfall can bring!