Effect of Snowmobile Noise on Small Rodents

Abstract

The relationship between immediate activity response and snowmobile noise level was measured for 30 female white mice ranging in age between 90 and 120 days. The mice were divided into three groups: the first was exposed to 85±4 dB (flat); the second to 95±4 dB (flat); and the third was a control group. The sound was a tape recording of several snowmobiles. The predominate tones were at about 500 and 1000 Hz. The mice were exposed for a period of 1 min for approximately three times each day. The experiment lasted for 24 days. Once each day the motion of each mouse was measured in an activity box during the exposure and for 5 min following the exposure. The data does not show a statistically significant difference in immediate activities between the exposed and nonexposed mice. The over-all stress response was measured by adrenal gland weight. At the end of the experiment, the adrenal gland weight was determined for each mouse. There was no statistical difference in adrenal weight per unit body weight between the exposed and control groups.