Re: Specimen fumigation The last few messages on modes of fumigation of dry preserved specimens make some interesting observations, but I have seen nothing to indicate what pests are being the problem, if any. I presume that insects are the main culprits, likely one or more species of dermestid beetles. However, booklice (not true lice), cockroaches, and other critters can be equally devastating. Freezing and inert gas fumigation are both viable alternatives to more typical pesticides, but both have severe limitations requiring accurate determination of the pest at hand. For example, dermestid beetles, depending on species, can tolerate normal deepfreeze temps for many hours, even days. Also, even if you freeze for a 3-4 days or a week, the adults and larvae may have been killed, but not necessarily the eggs; again, depending upon exposure duration. Similarly, inert gas use is not defined, but CO2 or N2 have their exposure limits as well. If short duration, the beetles will simply close their spiracles and await breathable air. Eggs can tolerate extremely low O2 concentrations for long periods of time; thus, repeated treatments may be necessary. The failure to begin with proper pest determination can cause serious problems in the museum, as much as in the crop field. ========================================== Paul J. Johnson Assistant Professor & Curator Insect Museum, Box 2207A South Dakota State University Brookings, South Dakota 57007 USA e-mail: [log in to unmask] ========================================== "By every conceivable measure, humanity is ecologically abnormal." - E.O. Wilson The Diversity of Life