Contributed by Emma Cook
For any museum institution with a vast collection and storage of artifacts, there is no holiday from IPM work! IPM stands for Integrated Pest Management and focuses on prevention of pests through preventative actions that protect museum collection environments from various pests. Examples of these actions include reducing clutter, sealing areas where pests may be entering the building, removing items that may be attracting pests such as food, and protecting artifacts that have the potential to be food or shelter to pests.
What’s important about this work is the long-term prevention taken to protect collections and their housing space. IPM work is not simply eliminating the pests, but looking at the environmental factors that affect the pest and its ability to thrive in its current conditions. Part of what museum staff do is use this information, and the observations made to locate potential pests, to create conditions that are unfavorable to pests and disrupt their occupied environment.
A large part of what Peabody staff do with IPM work is monitor the collection and building environments and identify potential threats or pests. The most common pests to come across in a museum collection space are various carpet beetles, webbing clothes moths, and case-making clothes moths. The type of pest one may have or attract depends on what is in the collection for the pest to eat. Most insect pests are drawn to animal and plant products such as wool, skins, fur, feathers, hair, silk, paper, horns, whalebone, and leather. As you can imagine, a museum collection looks a lot like a buffet to these insects.
The Peabody uses small insect sticky traps to monitor specific areas of the building for pests. These traps can catch insects and staff can then closely inspect these traps to understand what pests may be a potential threat and where they are occupying in the museum. It is always important to consistently check these traps as well as circulate new ones every so often.
Another form of monitoring for pests is through observation and identification. As staff rehouses and inventories the collections, they complete condition reports and inspections of each artifact that may be threatened by pests. If any evidence is identified on or around the artifact, further pest control must take place. The types of pest evidence that staff is looking for is frass, webbing, larvae carcasses, and live insects. Frass consists of the excrement of an insect and the refuse produced by the activity of the boring insect. Webbing and tubular-looking cases are present for webbing and case-making clothes moths. These are usually present in textiles and are made by these insects when they are larvae. Larvae carcasses are present when the insect sheds its larvae form into an adult. These carcasses are something to look out for with objects and their storage, as it demonstrates that an insect had once been there and the same kind of pest could very likely return. If an insect or evidence of an insect are found, staff then must try to identify which insect is the threat and begin pest control and further prevention from the artifact and surrounding collection.
Artifacts with evidence of insect activity are cleaned and rehoused with new acid-free tissue paper. The box holding the artifact is also cleaned. Once the artifacts are placed back into their box storage, the box is sealed in a large, acid-free plastic bag with little to no air in the bag. The box is then wrapped further in another layer before being placed in the freezer for low-temperature treatment. This type of treatment control helps eradicate pests from the artifact through freezing. After a few weeks of freezing, the artifact is inspected again by staff to determine if there is any additional evidence of infestation. If the artifact has no further evidence of insect activity, the artifact will sit for a few more weeks, sealed in a plastic bag, through a process called bagging or isolation. After another few weeks a final analysis will be given before the artifact is deemed safe to return to its original storage in the collection.
There are several other treatments that are used amongst museum professionals to control pest infestations in their collections. These are heat treatment, the use of pesticides in collection areas, and controlled atmosphere through nitrogen/argon gas, carbon dioxide, and depleting oxygen levels. The treatment that is used on each artifact depends on the artifact’s material. Some treatments cannot be used on all objects and it is important to always keep the artifacts’ well-being in mind.
IPM work requires a careful eye and patience, along with a resilience to properly eliminate pests and protect collections from future threats of infestation. To learn more about Integrated Pest Management visit Museum Pests, a product of the IPM working group.