DTY German Cockroach Management
Monitoring Cockroach Mayhem
Strategies for detecting evidence of cockroach activity.


Pest infestations are crime scenes. Pest management professionals (PMP) are crime scene investigators. Successfully solving and preventing future pestiferous crimes involve monitoring cockroach mayhem.

In forensic science, Locard’s exchange principle holds that the perpetrator of a crime will bring something into the crime scene and also leave something behind. In other words, no pest commits a crime without leaving a trace of its presence and/or changing the environment. The longer the perpetrator was on the scene, the more evidence there will be to discover.

Investigative Strategies
The primary method to understand a crime scene is the use of monitoring devices. Additionally, pest-sighting testimonies from personnel must be investigated, even though “recollection” sightings can be unreliable due to the vagaries of human memory.

It is critical to properly identify the perpetrating cockroach species. Correct identification provides essential cockroach modus operandi via biology and behavior. The cockroach species determines crime scene locations.

Learning from Monitoring Devices
As a general rule, the main purpose of crime scene investigation using monitoring devices is to obtain actionable pest evidence. Many monitoring devices are not designed as a method of pest population reduction.

During an investigation place monitoring devices in the most strategic positions to provide the best physical evidences. Pest detectives will determine position from knowledge of pest biology, behavior, and the physical site layout. Final monitoring device position is generally a compromise between the best possible site, its accessibility and whether or not the monitor will remain undisturbed.

Adhesive monitoring traps are effective for monitoring cockroaches in three dimensions. Label monitoring traps with an arrow to indicate their orientation as traps may become dislodged during use. This allows placement back into the correct orientation for additional monitoring. Additionally, labeling traps with arrows indicates the direction the cockroaches are entering the trap, which provides further clues as to the characteristics of the perpetrator and infestation.

Large adhesive traps may be used where pest infestations are heavy. Where pest infestations are forecasted to be light, deploy a greater number of smaller adhesive traps. Some adhesive traps incorporate food and pheromone lures.

The presence of cockroaches in a monitoring trap provides essential physical evidences of the species as well as the scope and age of the infestation. Determining the scope of a cockroach infestation will require several monitoring traps.

The number of cockroaches trapped depends on several factors, including:
  • The initial size of the infestation.
  • How long the traps have been in place.
  • Trap effectiveness.

Thorough surveillance through monitoring provides essential physical evidence for best allocation of pest management resources. Look for fecal smears and droppings, cast cuticles, egg cases and live and dead cockroaches. Heavy cockroach infestations often have a characteristic smell.

Captures found in monitors serve as essential crime scene evidence of recent cockroach activity. Presuming the monitoring traps were refreshed on the last inspection, any cockroaches found will have emerged within the intervening period. Adhesive traps can actively detect cockroach perpetrators 24/7 for 365 days a year. Therefore, they provide both a “video” and a “snapshot” of cockroach activity.

Understanding Cockroach Behavior
A study concluded that populations of cockroaches make collective decisions about harborage or refuge. When a space was large enough for all of the cockroaches, all remained in place. When a large space was not available, cockroaches divided into equal groups to fit into the smallest number of other spaces.

Monitoring cockroach mayhem allows PMPs to see the LITE and to effectively manage the pests.

  • Locate German cockroaches based upon foraging behavior.
  • Identify German cockroaches down to species.
  • Treat for German cockroach infestations based upon biology.
  • Exclude German cockroaches and prevent re-infestations.

PMP’s Direct To You provides pest management professionals with educational refreshers on timely and critical topics essential to operational success. This content is not to be used as a substitute for obtaining legal advice from an attorney licensed to practice where you live. Look for the content-rich PMP Direct To You archives at mypmp.net/direct-to-you-archive.


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