Today we’re talking about pests, and no I don’t mean your little brother who keeps running in circles and poking you, I’m talking BUGS and other creepy crawlies that can cause harm to cultural heritage objects.
Pests are living organisms that can damage and destroy objects so we’re talking about microorganisms, insects, rodents, all those things. A good rule of thumb is if you don’t want it in your house, you don’t want it in your museum or storage room either. (Don’t get me started on people who have mice and rats as pets).
There are, of course things like this that don’t count as pests, like spiders and centipedes... in fact they eat pests! That being said, you probably don’t want them either because that means pests could be nearby, and also when they die, their bodies become food for pests. Nature, you guys, it’s all about the circle of life. Ladybugs are also considered quote good pests, which is like… a relief! Who wants to hate a ladybug?! But of course, we don’t really want them trolling around collection storage either.
Let’s get in to these pest subtypes:
Microorganisms such as fungi, moulds and bacteria are everywhere. They can be airborne and brought in in a varying amount of ways. Bacteria can also be brought into a collection by contaminated flood or standing water so there’s our agent water up to its no good tricks again!
For bacteria to survive and thrive there needs to be a generally high relative humidity in the area. And we’ll be talking about relative humidity in another video as it is also an agent, but imagine a humid, wet environment. This is where bacteria love to hang out.
Moulds and fungi are also dependent on water that is in an object. They need moisture to germinate, but once they’re fully fledged, their spores can spread in the air and find another juicy place to take up residence.
Microorganisms can digest, eat, stain and attract other pests and insects as some insects and animals like to eat that stuff. Microorganisms also pose health risks to people because they can cause allergic reactions and respiratory problems.
Insects are the most numerous of the pests in the animal category. Think of moths, silverfish, termites, bookworms, and all the fun things that like to eat delicate organic museum objects. Each insect has their own palate let’s say and they’re attracted to different types of materials so you’ll have to be on the lookout for different species based on what your objects are comprised of.
Rodents like rats and mice like to gnaw on materials that will help to sharpen their teeth. They usually come on the scene when there’s a decent food source so mitigating that is key. Rodents shed a lot of hair and leave being a lot of poop, which can attract keratin-and protein eating insects which can then spread to other collections.
Birds and bats:
Birds and bats like to build nests, so they might take bits and pieces of organic objects in order to do so! They also love to poop and other pests love to eat it. Their nests can also contain parasites, which is not fun. And too much poop can cause health hazards to people.
So we know who our pest friends are. Now let’s get in to what they want and what materials and objects are vulnerable.
What these pests are looking for, are alternatives to what they would find in the natural world. Seeing as they’ve somehow found themselves inside,
With mould, every organic and inorganic surface is susceptible if the conditions are right. We talked about those a bit earlier, but damp things are the chocolate ice cream of mould. Cellulose and proteinaceous materials like paper and parchment are particularly susceptible because they’re porous, soft and super easy to digest.
Insects will eat a variety of things, but as I said before, they are very individualistic to the types of material they like. Silverfish eat paper, silkworms eat silk, termites eat wood, moths love textiles, etc.
Rodents love to chew, so anything that gives them a good bang for their buck is open game. They also like to gather things for nesting like insulation and packing materials.
Birds and bats are more harmful to structures than they are to objects. Nesting can become a problem, and when they poop or die, a lot of pests come for the buffet.
So how can we prevent pests from ruining our lives?
First thing to do is to remove or limit things that would attract or feed pests. Use protective barriers like containers or other practices to deter pests from finding their way in. Don’t eat or bring food into areas where collections are because no matter how tidy you are, you’re going to leave crumbs and a bug is just salivating, waiting for you to drop it. Brining in plants and soil into museum areas are also probably not a good idea because there could be bugs hiding in there.
Keeping a low relative humidity is important to stop mould and bacteria growth. Museums also use glue traps to catch bugs and shield vents to prevent rodents and birds from coming inside.
You want to be monitoring your collections regularly as well in order to catch any early signs of infestation. When a new object comes in to the museum, it’s a good idea to put it in a quarantine room in order to make sure nothing has come along for the ride and if it did, then it won't get in to the rest of your collection. A lot of places freeze objects or remove oxygen from them in order to kill anything hiding in the nooks and crannies. On the opposite end of the spectrum, some people use heat, or heat from the sun with objects in special pillows.
Museums implement things call Integrated Pest Management Programs or IPMs for short. They are essentially risk assessment and action plans in order to reduce the chance of pests coming in contact with collections. There are a lot of different techniques and ways to prevent pests. As not every institution will have the same environment or resources, these plans are written specifically for each institution.
Looking to find out more?
Canadian Conservation Institute- Agents of Deterioration: Pests by Tom Strang and Rika Kigawa