Beating the creepy-crawlies - Museums Association

Beating the creepy-crawlies

Pest control may not be glamorous, but it's increasingly vital for the safe-keeping of museum collections, says Louise Gray
“Liverpool museum is looking for ship rat bodies (ten if possible) for a display at the new dockside museum.” This advert appeared in August 2008 on the website of the National Pest Technicians’ Association.

Happily, Sorex, a Widnes-based pest-control company, came to the rescue and so it was that Tony Parker, assistant curator of zoology at the World Museum Liverpool, found himself returning to Liverpool with ten dead black rats in his bag.

“We needed them in a hurry for a display in the new Museum of Liverpool [which opens in 2011],” Parker says. “Black rats used to live on ships, but they are harder to find these days, hence our plea to the community of pest controllers. The rats are now in our taxidermist’s fridge awaiting stuffing.”

As far as Parker is concerned, the best rat is a dead rat. Like most museums, Liverpool is normally more concerned with keeping rats – and other pests – out of its premises.

But this is not easy to do. All buildings have a natural rate of decay that needs to be monitored and acted on, and this will often involve watching out for the insect predators that accompany this process.

Usually it’s not the big things – rats, squirrels and birds in the attic – that cause the problems. The real enemies are moths, so dangerous to textiles; carpet beetles (and their larvae, woolly bears), which like to eat textiles and book-binding glue; booklice; and woodborers such as death-watch beetles.

One of the problems for pest controllers is that there has been a huge change in the nature of pests in Britain. Entomologist and independent consultant David Pinniger gives advice on pest issues to many museums and heritage organisations, including the British Museum, National Trust for Scotland, English Heritage and the Imperial War Museum.

Pinniger is responsible for devising and implementing integrated pest management programmes (IPM) across the UK. “There’s been a spread northwards of insects that would have once found Britain too cold a habitat,” he says.

He cites the Guernsey carpet beetle and the vodka beetle, a brown carpet beetle that was named by the Victoria and Albert Museum’s (V&A) preventive conservator Val Blyth. (Its entomological name is Attagenus smirnovi.)

Museum conservators agree that integrated programmes are necessary to protect collections. Insects can move rapidly, and a proper strategy, which includes trapping, identification and discussion of treatments and preventative techniques, is the best route to take. Pinniger says that each organisation needs a lead officer on pest issues.

London-based Dee Lauder is the collections pest control manager at English Heritage and is part of its collections conservation team. She oversees and manages the IPM at the organisation’s houses, stores and sites where collections vulnerable to pests are stored.

“Pest controllers operate in the background,” Lauder says. “We are, in one way, the invisible guardians of collections.”

English Heritage’s IPM was set up by conservator (and now head of collections conservation) Amber Xavier-Rowe after a nasty incident with a flag.

“In 1996, we opened a cupboard to get an historic flag to find that it had been munched by woolly bears. It was this experience that instigated our IPM,” says Lauder.

English Heritage’s IPM covers 72 sites and involves three distinct stages: trapping, in which traps are set up for insects and then checked every three months by staff trained in identification methods; good housekeeping; and treatments.

The weapons in the arsenal of pest controllers change all the time and Lauder says one of their jobs is to be on top of the legislative changes.

Vapona, once the scourge of household moths, is now banned because of carcinogenic scares, says Pinniger. “The Natural History Museum and the V&A were two museums that once used large amounts of Vapona.

"It worked. Moths only had to get a whiff of that and they fell over. Thirty years ago, we barely saw any moths. We’re now seeing a big rise in clothes moths. This cannot be coincidental.”

“If we have to carry out a treatment – and that doesn’t happen often – we try to use natural methods such as freezing or heating,” Lauder says. One chemical they do use against a broad spectrum of insects is Constrain, a water-based spray with a low toxicity.

The most common pest at the V&A is the webbing clothes moth, but there has been no major infestations because the museum’s IPM is effective, says Val Blyth.

She coordinates the IPM programme, chairs the pest management group, which meets quarterly, and supervises the monitoring of the site by collections and conservation staff.

Each year, there are training sessions and pest-identification sessions. “We routinely treat objects at low temperature as preventive measures. This is important for incoming loans,” she says.

Three years ago the Royal Air Force Mus-eum in Hendon had a bad case of clothes moths in its offsite collection in Staffordshire, says Andrew Cormack, its keeper of visual arts, medals and uniforms.

“We found a live moth infestation inside a pair of furry flying boots,” he says. “Although it hadn’t caused much damage, we couldn’t afford to take any chances.”

The museum called in Thermo Lignum, a company that has developed a process that involves sealing objects in a chamber where temperature and humidity are carefully controlled.

Used by the V&A, Historic Royal Palaces and many other heritage organisations, Thermo Lignum offers a treatment that will kill any stage of insect infestation within 24 hours and is effective against a wide range of pests and fungi such as dry rot.

“We spent three weeks loading and unloading uniforms in and out of the chamber,” says Cormack. It was, he says, “an expensive and time-consuming process.”

Ian Fraser, a conservator at Leeds Mu-seums and Galleries, points out that pest control is often an issue of buildings management. He cites cases of woodboring beetles at Burton Constable Hall, near Hull, where the care and management of the collection is under Leeds’ control, and carpet beetles at Lotherton Hall.

“At Burton Constable, it turned out that the damp conditions the beetles need to survive was created by some bad 1970s re-roofing,” he says. “At Lotherton Hall, near Leeds, the problem was also in the roof voids.

Carpet beetles are protein scavengers and they were feeding from dead birds in the attic. The solutions in both these cases was on a macro level, but once the problems were understood, they were dealt with very quickly.”

Lauder says: “I cannot stress too much the importance of good housekeeping in pest prevention. At English Heritage, we regularly sweep, vacuum and deep-clean our properties. Costumes are checked and hand-vacuumed. If there are any signs of infestation, they are wrapped up and deep-frozen.”

The public also pose risks. With many museums and heritage sites hosting private functions, there are lots of things that managers need to look out for – and not the odd sandwich stuffed down the back of a radiator.

“Flowers can house insects and these need to be checked,” says Lauder. “So do Christmas trees, so we have a procedure for checking them and sometimes pretreating them with Constrain. Before logs are brought inside, we freeze them for two weeks.”

Cleaning is not a sexy subject, but Pinniger warns that it’s too important to let slip. Budgets are being cut and it’s the cleaning services that are the first to be clipped.

Staff need to be trained to monitor their environment for insects, be on guard against new species and be up to date on insecticide regulation. All this costs money – but there is no alternative.

“As an entomologist, probably one of the worst things I’ve seen is at one historic house,” Pinniger says. “The curator opened a drawer to show me a display of beetles; the whole collection was in pieces. Wings, legs, bits of frass – that’s insect poo – everywhere. The collection was utterly destroyed.”

Louise Gray is a freelance journalist

Don’t panic

In 2002, Jeremy Bentham, the philosopher founder of the University of London and preserved resident of a glass box in the south cloisters of UCL since his death in 1832, was found to have a case of woolly-bear infestation.

When moved, showers of frass – the dusty refuse left behind by insects and their larvae – fell from the brim of his hat. His auto-icon (that is, his preserved body) was packed off to the Textile Conservation Centre in Southampton (which closed in 2009) for treatment. Bentham is now back in his box at the college and on public view.

Good housekeeping

Keeping your premises clean and monitoring its spaces regularly for insects is essential, says English Heritage’s Dee Lauder.

Keep drainpipes and guttering clear to prevent infestations from woodborers such as deathwatch and furniture beetles, which find it easier to enter damp, soft wood – their attacks are costly to repair.

Chimneys needs to swept regularly, as birds’ nests and other items can get stuck in them, providing breeding grounds for clothes moths, woolly-bear larvae, fur beetles and other insects.

“In one of our stately houses, we found a very old rolled-up carpet stuffed up a fireplace – the carpet had caused an major infestation,” Lauder says. It had been up there for years and it was not a pleasant experience to remove.

Most important, adds Lauder, is an effective pest management programme tailored to each establishment, with seasonal checks of the premises and members of staff trained to recognise insects and larvae.

Coming soon?

Cockroaches are not seen often in museums; like mice, they need human food. “But they are a future risk,” says Lauder. Cockroaches are an example of a semi-tropical insect that exploits the building environment.

Another one to watch is the Guernsey carpet beetle, a new species of beetle found first in the Natural History Museum. “It has spread out across London,” says David Pinniger. “It eats textiles and breeds very quickly.”

Termites pose a greater problem, he says. “They have arrived in northern Europe. They will devastate all kinds of things – wood, paper, structures. I hope I will be retired before this becomes a problem in the UK.”

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