US Coins

Keeping the pests away

This is the third in a four-part series discussing integrated pest management.

You will remember that integrated pest management integrates pest management into the day-to-day activities of a facility. IPM has five steps — avoid, block, detect, respond and recover.

Last month, we were discussing the detection step that relies heavily on setting traps to monitor vermin and insect activity.

Trapping devices

Mechanical snap traps are best for trapping mice and rats. In my opinion, adhesive mouse and rat traps are inhumane. Contrary to the claims of the manufacturers, these traps often do not cause the animal to die quickly.

For trapping insects, though, adhesive traps are acceptable, and the norm.

Cardboard delta traps, named because they resemble the Greek letter delta (?), are the most common form of adhesive insect trap.

Delta traps can be placed discretely on the floor around the perimeter of a room near doors and windows.

These traps give you an idea what sorts of insects you are harboring.

If you set up a pest monitoring program, it is important to inspect the traps on a regular basis to determine if you have an insect problem.

Not all insects are “problem” insects for your collection. If you are only catching house flies and June bugs, then you have no need to be alarmed. However, if are catching silverfish and dermestids, you should be worried.

For the nonentomologist, identification can be difficult. The “image library” on can be a very helpful aid to identification.

Adhesive insect monitoring traps are available in both baited and unbaited forms.

Baited traps have an attractant (often a food source) built into them to try and draw the insects towards them.

Unbaited traps rely on the insects literally running across the trap. These traps are often referred to as “blunder” traps. Delta traps are blunder traps. Research has shown that blunder traps are less effective than baited traps.

Pheromone traps are a special variety of baited traps. Pheromones are used by insects to communicate with one another.

In this application, we bait the traps with a synthetic pheromone that mimics the female sex hormone. The male insects are lured into the trap thinking it contains females. Once there, they stick to the adhesive surface.

Pheromones are specific to each insect. Pheromones are difficult and costly to synthesize and only exist for a few insects. These traps are expensive, costing around $15 per trap. If using pheromone traps, it is important to have a clear identification of the insect that you are trapping.

Whether baited or not, it is important to replace the traps once they acquire a number of insects. The trapped insects themselves become a food source and attract other insects, especially dermestids.

Keeping records

Record keeping is also a part of integrated pest management. The “record keeping and recording” section on is a very good resource.

Included there is an opportunity to download a free copy of “ZPEST,” a computer program designed to organize and present pest management data.

Trapping is not the only means of detecting pests.

Look for signs of activity. Use your eyes and your nose. If something does not look right or smell right, check it out.

Many museums use traps and constant visual inspection to detect an infestation.

I will finish this discussion next month.

Susan L. Maltby, Toronto, is a private conservation consultant, with an interest in numismatic preservation.

Community Comments