Why the Uptick in Insects After Natural Disasters? 

Natural disasters can have consequences beyond displacing people from their homes and threatening their lives and livelihoods. Some types of natural disasters cause insect populations to grow exponentially — often the most undesirable species. Here we’ll examine which types of natural disasters bring the bugs out en masse and why extreme weather is frequently the culprit behind an uptick in insects. 

Floating Islands of Venomous Ants  

Imagine your neighborhood is flooded. From down the street, an island comes floating your way: one made up entirely of ants. Once they bite you to get a good grip on your flesh, the ants then inject you with a toxin that can cause anything from a stinging sensation to death. Those aggressive antsfire ants — live in at least 15 states, as well as in Mexico, Australia and several countries in Asia.  

Floods, whether caused by heavy seasonal rains, a tropical storm, a hurricane or possibly a tsunami, force subterranean insects such as ants, bees and wasps to seek new homes and food sources. Insects coming to the surface doesn’t necessarily mean there are more of them in the immediate area — they were already there, you just weren’t seeing so many. However, it does mean humans are more likely to encounter them and experience any risks they may pose. 

While some insects pack up and leave for drier neighborhoods after a flood, standing water that remains after even a small rainstorm can cause the population of blood-sucking, disease-transmitting mosquitoes to swell. As the Centers for Disease Control (CDC) explains: “All mosquitoes like water because mosquito larvae and pupae live in the water with little or no flow.” Further, the CDC reports that after a hurricane, “eggs laid in the soil by floodwater mosquitoes during previous floods hatch.” Floodwaters, past and present, drastically expand mosquitoes’ breeding grounds. 

Rain is of course vital to all living things. It helps grass, trees, shrubs, plants and flowers grow, providing a habitat and nourishment for insects, humans and other species. But substantial amounts of rain can lead to insects breeding in excessive numbers, resulting in greater health risks and discomfort for us and more frequent instances of unwanted visitors such as ants, roaches and spiders appearing inside our homes. 

Bone-Dry and Besieged 

As big an effect as flooding can have on insect populations, the opposite conditions are also problematic. A drought can disrupt a region’s normal growing seasons and “create conditions that encourage insect and disease infestation in certain crops,” according to the CDC. When water levels drop significantly, lakes and rivers may be reduced to stagnant puddles of water that invite mosquitoes as new breeding areas.  

Drought also causes insect-bearing wild animals in search of water to come closer to humans. With water and food sources drying up, insects that are used to drinking and eating outdoors also go looking for new water and food sources indoors. During a drought in California a few years ago, some homeowners found themselves hosting an alarming number of thirsty and hungry cockroaches. Unfortunately, whether conditions are too wet or too dry, roaches are ready to make themselves at home in your home.  

Not All Natural Disasters Bring Bugs 

While it’s clear that a region having too much or too little water can give rise to an insect invasion, natural disasters do not automatically translate to a boost in bug populations. Many disasters kill hordes of insects, inhibit their migration and/or interfere with their reproduction cycle. High-wind events, wildfires, volcanic eruptions and earthquakes — the latter of which some ants and bees can apparently see coming — can be unforgiving to insects, though a few of these phenomena are rare and occur in limited geographical regions.  

We Know a Thing or Two About Insects 

If you’re interested in helping limit the spread of harmful insects among our population, there’s no better place to start than the world’s number-one ranked entomology and nematology program — right here at the University of Florida. We offer online master’s degree and graduate certificate programs with specialties in urban and landscape pest management, as well as beekeeping and medical entomology. No matter which program you choose, you’ll enjoy the same advantages: 

  • No GRE requirement. 
  • No thesis requirement. 
  • No campus attendance requirement — courses and labs are presented entirely online.  

Wherever you are in the world and in your career, our online programs can help you get where you aspire to be! Review our programs or apply now

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