MICE PRE-EMPT STRANGE HOME
by Ranger Naturalist Harry Woodward

During the recent summer at Fishing Bridge, I became interested in the habits of mice (Peromyscus maniculatus artemisiae). These little rodents, sometimes known as deer mice, are among the most attractive of all the wild mice in the park. They seemed to be particularly abundant this summer, no doubt due to the fact that a series of favorable seasons from the standpoint of an abundance of food or a lack of natural enemies has improved living conditions for them.

I was interested in determining habits of the mouse as compared with the various types of the Neotoma family. This is the family which includes the packrat or trade rat and the various types of wood rats. These mice, however, are much smaller than the rats, yet in many other ways have similar habits.

One camper at Fishing Bridge had considerable experience with these mice. They found a way into his car by way of the openings in the floor board for the brake and clutch pedals. The first thing they did was to remove enough of the material used in the upholstery to make a warm, snug nest in the cushion of the front seat. The next thing he noticed was a rattle in the top which sounded like the rattle of rocks every time he drove the car. When he discovered the presence of the mice, he removed the nest and set a mouse trap baited with cheese. He succeeded in catching five of these little creatures. After removing the lining in the top, he found about a gallon of stones, peach pits, plum pits, pieces of bacon rinds, and other articles brought in by the mice.

The puzzling thing about it is how these mice carried all of this material up the spokes of the wheels of the car, through the small opening in the floor of the car, and then up the body wall to the top of the car. Some of the material was almost as large as the mouse itself. I am inclined to believe the mice jumped to the openings with their load in hand. There seems to be no other logical way they could get their load in.