QUESTION:

with the summer heat wave going on one question comes to mind as I bait attics for mice. How hot is too hot for a mouse? At what temp does a mouse find it too hot to inhabit an area?

ANSWER:

Well this is interesting. I looked in a number of our most authoritative references on mice and it seems that all the discusssions on the house mouse and temperatures are with respect to how LOW of a temperature the mice can tolerate. So, lacking an answer from one of our experts I turned to that magical reference library in the sky - the Internet. This also gives me the freedom to speculate at will with my answer. What is interesting is that the only (and therefore the best) information I could find was on websites pertaining to the care, feeding, and passionate loving of mice as opposed to anything on managing the little vermin.

Two items came up. One suggested that the ideal temperature for your little companions is between 65 and 85 degrees Fahrenheit, and that above 85 the mice begin to get lethargic, sick, and could die. A second website stated that mice will die if kept at a temperature of 104 degrees. Obviously the air temperature in an attic in the summer in many states is going to get well above 104 degrees, so if the mouse were confined in that airspace this could prove lethal to it. But, perhaps as the mice do in freezers, where they have been found living just fine, they seek out a place that is a lower temperature. In freezers they cozy up inside things to conserve body heat. In an attic perhaps they would nestle down under the insulation, where the temperature against the sheetrock of the ceiling below would likely be much cooler than the air above the insulation.

I would expect that a very hot attic is going to limit their activity but not necessarily exclude the mice completely if they can find these little micro-environments that remain suitable. A really hot attic might become a concern for paraffin baits that might be placed up there, so this could be one side effect for their control.

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