Book lice

Gretchen Voeks <gretchen_voeks [at] nps__gov> writes

>I am aware that book lice feed on mold but am wondering what
>potential risks they pose to collections?  Besides providing food
>for other pests, will book lice damage collections? Information on
>this issue, and any safe methods (other than freezing or lowering
>RH) of controlling these insects would be appreciated.

My understanding is that booklice and silverfish will both damage
starch-based materials (i.e. books, papers, photographs), even if
not mouldy, but prefer starches/foods with a higher protein
content--e.g. papers sized with gelatin, gelatin photographic
emulsions, flour paste rather than purified starch paste etc. Hence
they also like to munch on microscopic moulds and bacteria living on
various surfaces.

The damage from both appears similar--i.e. surface grazing. My
experience is that booklice and silverfish usually don't cause
damage as extreme or as rapid as that caused by clothes moths and
carpet beetles but can still cause a fair amount of damage if left
undisturbed. Collections without a regular housekeeping/IPM program
and those that lack adequate storage containers seem to suffer the
most, as you would expect.

As you are already aware, a combination of good housekeeping and
controlling high humidity levels provides the best chance of
prevention, but I thought you might be interested in the research
conducted by David Rees of the CSIRO (Commonwealth Scientific and
Industrial Research Organisation) Entomology Department (see
<URL:http://www.ento.csiro.au/>). He has spent many hours in grain
silos studying the habits of psocids (booklice), which are a large
problem within the grain industry. High temperature and high
humidity "hot spots" can form within huge piles of grain, fueling
outbreaks. Failure to adequately clean grain silos, particularly
around machinery, can also result in infestation of new crops.

Rees gave a paper at the Fifth International Conference of
Biodeterioration of Cultural Property, held in Sydney in 2001,
called "Monitoring insect pests within buildings using traps: case
studies of the use of traps to monitor activity, spatial
distribution and efficacy of pest control". This paper presents two
case studies, one looking at grain moths and the other at psocids.
Phosphine is used relatively regularly in the grain industry to
treat infestations, not always with success as survivors can still
reproduce quickly enough to cause major infestations. Results were
improved when phosphine and dichlorvus were used together, but in
any case this kind of large-scale fumigation is rarely appropriate
for cultural collections.

Papers from this conference can be found in the Volume 28 of the
AICCM Bulletin (2003/2004). This publication also contains papers
about low-oxygen and heat treatment methods, which may be suitable
alternatives to freezing in some cases. The heat method is a useful
"field" control method, at least for items not in danger of melting.

David Rees has also written a book called "Insects of Stored
Products", available from CSIRO, which may be of interest. And, in
case you haven't already consulted these, you might also find
various publications and papers by David Pinniger (UK) and Tom
Strang (Canada, CCI) useful. Tom Strang has written extensively
about IPM and using solar heat systems to treat infested items.
Pinniger has published papers about using pheromones as a control
method (see AICCM Bulletin #28 again), which can work on a small
scale provided there is an appropriate pheromone available (I don't
think there are ones for psocids yet but you never know).

Hope this helps,

Alice Cannon
Paper Conservator
Conservation
State Library of Victoria
328 Swanston Street
Melbourne, Victoria 3000
+61 3 8664 7331
Fax: +61 3 9639 6559
+61 402 041 064


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                  Conservation DistList Instance 20:49
                  Distributed: Friday, April 13, 2007
                       Message Id: cdl-20-49-001
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