A friend called who was concerned about mice entering her home. They had arrived suddenly and she felt that they might create permanent nests which could be an ongoing problem because of disease, destruction of property, and noise. She didn't want to use poison and had found that her mostly outdoor cat was not interested in routing the mice inside.

This is a subject that many of us have had a little experience with, but few of us, myself included, seem to know much about. A call to the Kenwood Wildlife Center, where Peter Gruchawka, Nancy Summers and

several other volunteers take a broad interest in wildlife, proved to be quite informative.

Peter suggests that there many things to know about mice that can assist in preventing them from setting up their home in your home. The more we understand the life cycles of animals and plants we are concerned about, the more we are able to work with them toward an outcome we desire.

A mouse has a life span in the wild of about one year. In years when there are plentiful rains, and the small plants and seeds that mice feed on are therefore plentiful, mice will have more frequent litters, as many as eight in one year. Mice are staple food for many birds and several mammals that are also part of these natural cycles. Barn owls, for example, will only lay eggs in years when mice are plentiful. Because this has been a wet year, it is a good year for mice in the wild, and we can expect that many living things are adapting to an increased quantity of mice.

Indoors, this bounty can be a problem. Many species of mice and even voles, a close relative of the mouse, will start looking for shelter in our houses as the cooler fall weather arrives. They usually enter the house from brush, plants and taller grass nearby and seek out cracks in the house. Because a mouse can fit through a crack or hole the size of its skull, or about the size of the tip of your little finger, a mouse can enter a house rather easily. Once inside, it will seek out a comfortable dark place to nest, often in a wall or behind a large fixture, and it will explore for food and nesting materials.

Several things can be done to discourage a mouse from nesting in your home. Peter defines the two major factors as food and access. Start by keeping the house sealed off from mice as much as possible. By keeping brush and grass away from the house a few feet, mice are forced to go into the open where they are vulnerable to predators. This will discourage them from exploring for a way in as well as from nesting inside and going back outside to find food. Use weatherstripping to seal doors and steel wool as a means of blocking off small holes. Keeping food in sealed containers, and keeping floors and counters clean of food scraps is a good way to discourage mice from becoming comfortable with the inside of your house as a source of food.

Removing mice that are already inside requires some creativity, especially if you wish to avoid using poison. Cats of course are one of the more proven methods of mouse removal. There are several varieties of mechanical mouse trap available at most hardware stores which crush a mouse. Seabright Laboratories in Emeryville ((510) 655-3126) makes a live trap called the "smart mouse trap", which efficiently traps mice and allows you to take them into the wild to release them. It comes with clear instructions and some good advice. Peter suggests that a mouse should be released at least one mile from your home, preferably in blackberry or other brush.

Following these basic guidelines, my friend was able to rid her house of mice within two weeks.