Q&A Special: How do you handle Pests?

Those pests which cohabit with museum objects are no lightweights. They know how to survive and they do it under extreme conditions. A museum environment with its dark corners and large amounts of organic material, is the equivalent of a five star hotel to your average cockroach or silverfish. If you add high humidity into that mix then the clients you can attract will expand to include the Mould Family and the Fungi Group Inc.

'Know your enemy' is a valuable maxim for the museum worker, with the rider 'never underestimate them'. The damage they cause can happen quickly. Pests love to work overnight and the results of their labours are devastating.

Pests in the museum environment (human examples aside) span a good range of the large and small marsupial, rodent, bird, insect, mould and fungi life forms. The intensity of their desire to eat, sleep, defecate, procreate and put in some quality recreation time in your museum is directly proportionate to the level of comfort and accessibility which you provide for them.

Generally, your large or small marsupial or rodent is attracted by a safe entry and exit point, and some peace and security once they have arrived. Blocking off access is therefore important; for example check for loose tiles or fascia boards and ensure that there are no detaching skirting boards. Possums are a protected species and require special consideration in relation to eviction. However, rodent baits are an effective means of controlling mice and rat infestations.

Birds generally fall into the 'bewildered visitor' category in a museum. That is they are not sure how they got in, they have no idea how to get out, and the reasons for being there are not clear to them. Common sense (avoiding leaving doors open, blocking in obvious entry points in roofs) can pre­empt the dazed and confused bird. Once in, a calm, systematic approach generally incorporating a pincer movement, is the most successful eradication tactic.

Insects, on the other hand, are small, quick, cunning and quiet. Often insect damage is not obvious until after severe damage has been done. With 'The Insect' eternal vigilance is essential. Insects eat, defecate, breed and die. All stages can result in damage to museum items. Silverfish, cockroaches and moths are common pests which cause damage by using museum and archival items as a food source. Their dead bodies and faeces can also stain items and cause rot in organic material. Other insect pests cause most problems in the larval stage where they burrow or bore through material or build cocoons within material. As the larvae grow they also feed on their surroundings. Insects dislike housekeeping being carried on around them. They resent the disturbance and dislike cleanliness. Therefore good housekeeping practices are the best weapons in the defeat of 'The Insect'. Regular cleaning, good air flow, the use of appropriate chemicals and other techniques (as deterrents and for killing), eradication or isolating of food sources, the use of insect traps and regular inspection are critical in minimising insect damage to your collection.

Mould and fungi spores prefer damp areas in order to develop into fruiting bodies. It is therefore important to avoid the development of microclimates within a collection, however once the spores germinate mould and fungi create their own microclimate by absorbing moisture from the air, creating damp spots and further fuelling their growth. Mould and fungi grow best in warm, dark, damp areas with little or no airflow. Maintaining stable humidity in the range 45-55%, and certainly no higher than 65% is important. Avoiding cross contamination from mould spores travelling or brought in from other areas is also important.

Damage to museum collections from pests is widespread, yet generally preventable. Common sense and vigilance are the best defence. Remember also that pest control often involves the use of chemicals or poisons that can adversely affect human health, and following good health and safety procedures is therefore very important. The literature on pest management is constantly being added to and updated. A good overview is presented in the reCollections volume Damage and Decay.1 While pest control companies can provide good advice they are often not aware of the special needs of museum collections. For example, some fumigation chemicals can damage organic materials, others can lead to corrosion of metals and some may contain other materials such as oils which will stain objects. If you require specialist assistance you can seek support from conservation staff in the major institutions.

Pests that are common to museums are common elsewhere. They are the original and most successful exponents of globalisation, and will takeover and restructure your valuable assets to their advantage whenever your defenses are low. It is a very important maxim in relation to pest control in museums that 'Prevention is Better Than Cure'. A three pronged approach of securing your area, checking for infestation and taking immediate action is essential. You can generally stop pests before they enter the museum, you can make conditions inhospitable for them once they have entered, and you can exterminate them upon discovery. Each step involves more knowledge, more energy and more cost than the previous. And the simplest approach of regular housekeeping and regular checking will lessen the amount of anguish and work an insect or other pest can cause.

They may be small, but they are very effective - never underestimate the enemy!

Robyn Sloggett, Deputy Director and Grimwade Chief Conservator, Ian Potter Museum of Art and Ian Potter Conservation Centre, University of Melbourne, Telephone (03) 8344 7989 or ou can visit the Ian Potter at www.art-museum.unimelb.edu.au

1. reCollections was handed out to most small museums as part of its launch and workshop 18 months ago. Otherwise people could contact: Paul McInnes, (02) 6271 1094, Email: hcc@dcita.gov.au or get a copy online at www.amol.org/recollections Members can also come into the MA (Vic) office and view our copy.

 

Ed. For additional online conservation resources try these: http://www.austmus.gov.au/science/division/matcon.htm
http://palimpsest.stanford.edu:80/

 

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