If you have squirrels in your storage areas you have more issues than just the squirrels. If squirrels have access to an area, so do nearly all other agents of deterioration, including other even more damaging/dangerous vertebrates like bats, coons, cats, etc. There are more variables to consider when dealing with and predicting behavior of vertebrates than with arthropods but squirrels should be easier to exclude than arthropods from even the most basic of collections storage areas. Glue is certainly not a preferred food source and, though cardboard is a good nesting material, these are not resoiurces they will work too hard to obtain under most circumstances. As with the previous posts about hibernating insects, make sure all holes and access points are patched and sealed. With squirrels it may be necessary to cover an area with sheet metal since, once they find a place they like to sit and gnaw, they may return to a wooden patch and open it again. Ammonia soaked rags placed or tied in the area are irritating and usually avoided. Tanglefoot is annoying to them. Repellents are a good occasional control method but squirrels can habituate to them; use them in conjunction with other control methods. Monitor historic and potential entry points rigorously and make them unpleasant places either with the above methods, Christmas lights, monitors with squirt guns, vegetation modification, kinetic sculptures, etc.
Relocation is usually a bad idea from both pest control and ecological perspectives. The squirrels either return or die miserably from fights, starvation, weather, or predation. Trapping and euthanasia is the most humane and effective course, just like we do with all other museum pests. Squirrel populations can tolerate up to 80% annual mortality and still maintain long-term stability. You can use live traps and CO2, big snap traps, and other control methods similar to that used for rats, though local regulations vary because squirrels are a game animal. Sometimes it seems that the population learns to shelter in buildings from a few individuals so concerted trapping for a few seasons eliminates the problem individuals and for sometime later there aren't any problems. Eliminating outside food and nesting areas for squirrels can be difficult since these often come from legacy trees and their mast. However, if squirrels are being fed near the building or are regularly using garbage cans you can enact policies to manage this. Also, I would approach the "old lady who swallowed a fly" method of eradication with care. In most cases this has poor results, at least for the introduced animal which usually dies a miserable death and, if not, it will negatively affect more than just the intended target. Feel free to email or call if you want to talk about your specific situation and discuss particular methods. In the meantime, I hope everyone will tell me about the squirrels near them at ProjectSquirrel.org <http://projectsquirrel.org/> . --Steve Steven M. Sullivan | Curator of Urban Ecology The Chicago Academy of Sciences and its Peggy Notebaert Nature Museum Museum | 2430 North Cannon Drive | Chicago, Illinois 60614 | naturemuseum.org <http://www.naturemuseum.org/> Collections Facility | 4001 North Ravenswood Ave. | Chicago, Illinois 60613 | ProjectSquirrel.org <http://projectsquirrel.org/> 708-937-6253 | Fax 773-755-5199 | [email protected] The Urban Gateway To Nature And Science From: [email protected] [mailto:[email protected]] On Behalf Of Dennis Piechota Sent: Wednesday, October 06, 2010 12:45 PM To: [email protected] Subject: [pestlist] Squirrels I hope this is the appropriate place to ask about larger urchins. We have a storage area for archaeological materials (almost all inorganics, typically ceramics, stone and iron) that keeps getting attacked by squirrels. They like to eat the glue in our corrugated boxes, thus destroying our provenience data. Then they will sometimes nest in the boxes! Very disheartening. We keep trapping them and plugging up their outside entry points. We prohibit all bonafide food sources from storage and are now switching over to glueless twin-walled polyethylene cartons with duplicate labelling. Still with all that I've learned not to under-estimate these critters. Is there anything else we can do? Dennis Dennis Piechota Conservator Fiske Center for Archaeological Research UMass Boston Office: 617-287-6829
