Mice

To some, mice are tiny, adorable creatures. To the rest of us, they are destructive, disease-carrying pests.

Mouse (Alexas_Fotos) Pixabay

Mice are members of the Mus genus unless they happen to be deer or field mice (Peromyscus). There are several types of Mus mice, the most common being the house mouse. There are also white lab mice and mice sold as pets.

Mice have followed us throughout history. We provide easy food sources and shelter, often against our will. Mice are intelligent, curious creatures.

Mouse description

Most of us recognize a mouse when we see one. Its pointed snout, cute little rounded ears, and naked tail are clear giveaways. Or are they? It ends up that the words mouse and rat are not taxonomically specific. In this case, size really does matter. In Ancient Roman times, rats and mice were differentiated by size, calling them mus maximus and mus minimus, respectively.

Descended from an ancestor shared with lagomorphs (rabbits), these species went their separate ways several million years ago. All of them are highly prolific gnawers. Gnawers have some amazing teeth. The reason these animals keep gnawing on things is that their teeth grow continuously. In the photo below, you can see a single lower incisor tooth below the rabbit jaw from which it came. The tooth fits neatly into a tube in the jawbone, and it is always moving outward.

Rabbit jaw with one incisor removed (Kate Russell)

Mouse or rat?

One of the easiest ways to tell if you have a mouse or a rat today is to look at its nipples. Rats have six pairs of nipples. House mice have five. But who’s counting? Other differences include the larger ears and thinner tails of mice. Mice and rats are both excellent climbers and swimmers, but mice can jump surprisingly far, for their size. Mice and rats have poor eyesight but their senses of hearing and smell are excellent.

Mouse lifecycle

Mice generally only live one year, but a single mouse can produce an astounding number of offspring. She can have 5 to 10 “pinkies” in each litter. As soon as they are born, she can breed again. She may have up to 10 litters in her lifetime, and each of her pups becomes sexually mature at 4 to 6 weeks of age. It is estimated that in a world of perfect safety with plenty of food and water, a single breeding pair of mice can be responsible for over 5,000 offspring in one year. Other estimates are significantly higher.

Baby 'pinkie' mice (Muhammad Mahdi Karim) CC BY-SA 3.0

Mice build their nests in tiny pockets of darkness. Those pockets may be found in burrows or any number of neglected spaces in your yard or home. Mice may be small, but they can cause big problems.

Problems caused by mice

Mice may have impressive teeth, for their size, but those teeth are softer than a rat’s. Instead of chewing through concrete and aluminum, mice prefer softer materials, such as wires, irrigation bags, and plants. Mice chewing on electrical wires have been known to cause housefires. They can also create new openings in your ductwork and damage anything you have stored out of the way for safekeeping. It ends up “out of sight, out of mind” isn’t particularly safe for your treasured holiday decorations or mementos when mice are nearby.

In the garden, these herbivores prefer fruits and grain for their food, but they will take whatever they find. Contrary to popular fiction, mice are not especially fond of cheese. [I imagine it gets stuck in their teeth.] Instead, they will strip your cereal grains, ravage your nectarines and persimmons, and make short work of your peas and beans. Look for tiny teeth marks on pods, fruits, and stems. They will also pull seedlings and small plants down from underneath to enjoy in relative safety, along with newly planted seeds. If your seeds and seedlings have been disappearing, mice may be the problem.

Field mouse on barley (Charlie Marshall) CC BY 2.0

Mice are also responsible for spreading diseases such as hantavirus. Hantavirus causes kidney damage and failure. The disease is spread through mouse urine and feces which are found everywhere mice go. No pun intended.

Mouse management

In my experience, a traditional mousetrap smeared with crunchy peanut butter is the best way to trap mice. You can add other nuts and seeds to the peanut butter mixture as an added attractant. One minute a mouse sees food. The next moment, its life is over. When your trap is successful, don some gloves and a mask, remove the mouse from the trap and place the mouse in a plastic bag before depositing it in the trash.

Mousetrap (PublicDomainPictures) Pixabay

There are also electronic traps that electrocute its victims. Live capture traps can also be used, but those mice must be released somewhere else, potentially spreading disease into new areas and disrupting the delicate balances of life that exist there. As prolific as mice are, I opt for the kill trap method. Do not use poison or sticky traps. They are cruel. Sticky traps leave their victims to starve to death and poisons put pets, small children, birds of prey, and many other creatures at risk.

Small dogs and cats will go after mice, but only if they are left out all night, every night. In my opinion, the damage they may cause chasing a mouse outweighs the damage they prevent. Since cats tend to choose garden soil for their “business” and outdoor cats are more prone to injury and disease, I feel cats belong indoors. That’s just me.

Tarantulas will also kill mice, but I don’t want one of those running around loose in my strawberry patch. How about you?