To the Editor:
May I, as the cause of the letter from Dr. Parker regarding the "wives" tale of dermestid colonies being a threat to museum collections (October 1993 issue), add a couple of small but important points.
Although dermestid colonies used for cleaning up skeletal material do not pose a great threat to museum collections, it would be wrong to say they pose no threat. As Dr. Parker states, both adult and larval forms are highly mobile and unless strict preventive measures are taken, can escape into other areas of a museum. Insect glue boards and electrocuting insect traps are not 100% effective at catching all escapees, and poor management and design of dermestariums can pose a risk of lack of containment of the insects.
Dermestes species are well recorded as attacking and damaging museum collections and infesting museum stores. One UK museum has a deep-seated infestation of Dermestes peruvianus, and a major Canadian museum has reported Dermestes sp damage to Amerindian ethnographic collections. In my own museum, we have encountered severe Dermestes maculatus damage to prepared comparative bone collections, freeze-dried animal specimens and oak-bark cured skins and hides. The infestations were encouraged by damp, poor storage and display conditions and bad preparation of specimens.
My point is that we know the conservation standards that will prevent deterioration of our collections but sometimes it is difficult to achieve them. As a result, even low potential threats such as that posed by the dermestid beetle need, at least, to be borne in mind in an integrated pest control program.R.E. Child