What are occasional invaders and why do they enter your facility?

Nancy Troyano

Among all different pests found in the United States, you might be familiar with some of the species that are considered structural pests. These are the ones that infest areas to breed, feed and develop, such as rodents, ants, cockroaches, and bed bugs, to name a few. However, there are other pests that invade places – especially buildings – on specific months due to the extreme weather conditions outside, or even accidentally. 

These pests are called occasional invaders, and, despite being a nuisance more than a threat, their presence indoors is a warning of entry points for other pests, as they make their way in via cracks and crevices in foundation walls and around doorways and windows.

What pests are classified as occasional invaders?

Some of the pests classified as occasional invaders include, but are not limited to, the following insects and non-insect arthropods:

  • Clover mite
  • Crickets
  • Earwig
  • Ground beetle
  • Millipede
  • Pillbug
  • Springtail

Rentokil data from 2017-2018 shows that occasional invaders spike between May and September at commercial facilities. That is exactly when extreme weather conditions – such as heat, humidity, moisture, or dryness – are present.

They appear across all industries, but some businesses have had more occurrences, such as Multifamily, Pharmaceutical, Manufacturing, Food Processing, and Retail

Although these pests are not likely to cause any structural damage, some can harm papers and fabrics, such as crickets. Others may harm grass and plants, such as clover mites and earwigs. 

Their presence indoors works as a warning, as occasional invaders make their way in via structural gaps. Occasional invaders are of even greater concern at facilities where edible products are processed. If one of these pests gets in contact with the product itself, the product is considered contaminated or adulterated. Springtails are a classic example of a pest that invades in very high numbers. These large populations make it easy for them to accidentally coming into contact with clean areas or products. And if they can get in, so can other higher-risk pests.

earwig on wood structure

How to stop the invasion

Preventing and controlling occasional invaders is not a complicated task. Below are five easy steps you and your staff can take to make sure they won’t make their way inside: 

  • Inspect your facility for any potential entry points;
  • Seal any cracks and crevices before the first frost; 
  • Ensure windows and door frames seal tightly and are not damaged; 
  • Install door sweeps to tighten the gap at the base of doorways;
  • Eliminate moist harborage sites around the perimeter of the building, such as uncontrolled vegetation, mulch, leaf piles, etc.

If you have a small problem with occasional invaders at your business, you can use a vacuum or employ the ‘catch and release’ method. If the infestation is moderate to severe, or prolonged in duration, we recommend you get help from a professional pest control expert.

Rentokil specialists are highly trained to properly identify occasional invaders and formulate a management strategy for your facility. Contact us online or call 1-888-268-8853 to speak with one of our experts.

Nancy Troyano
Nancy Troyano

Nancy received her PhD in Entomology from Virginia Tech, with research primarily focused on virus transmission by mosquitoes. Nancy is also a Board Certified Entomologist, skilled in medical, veterinary and urban entomology. In 2009, Nancy began working for Rentokil North America, a billion dollar organization, where she currently serves as the Director of Operations Education and Training. Nancy is responsible for leading and supporting education and training for all lines of business and at all levels of the operation, which includes over 4500 pest technicians. She develops comprehensive academic programs and pest management courses that are utilized globally, and oversees a team that manages all of the learning and development needs of the organization. Additionally, Nancy provides ongoing technical support to field operations and acts as a subject matter expert for vector management programs.

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