About 40% of all mammal species are rodents, making them the largest order of mammals. These include rats, mice, hamsters, squirrels, porcupines, and their relatives.
Of these, only a handful of rats and mice are a nuisance to people, and we’ll be discussing the ones that may find themselves in our homes.
These rats are called pack rats because of their characteristic accumulation of food and various debris, which they keep stocked in their dens (or near their den area). Such collections may include edible plants, small pebbles, sticks, feces, insect and vertebrate remains, shiny metal objects, and other small items taken from humans.
Also known as woodrats, they have large eyes, protruding ears that are almost bald, and white-colored feet. They have long, thick and soft fur that can range in color from gray to reddish brown (and white to rust-colored on their underparts). Some populations of desert woodratsare black in color. Often confused with Norway rats, they have tails that are covered in fur.
They’re nocturnal and generally solitary. Bushy-tailed woodrats are vegetarians and prefer green vegetation such as leaves, needles and shoots, while Mexican woodrats eat fruits, seeds, nuts, and mushrooms. Some species also eat animal matter and small insects.
If they’re inside your home, they can damage electrical wiring, wall insulation, and pipes. They make off with small objects such as jewelry (remember, they like shiny metal objects), and they bring these items to their dens, which are lined with urine and feces. They’ve also been known to rip out padding from cushions and pillows to use as lining in their nests.
Pack rats carry diseases including the plague, and their dens and droppings are also a health hazard.
Also known as black rats, roof rats have black or dark brown colored fur with a lighter underside. They have long, hairless tails that measure longer than its entire body. They’re called roof rats because of their tendency to nest in the upper levels of the home such as attics, and they’re excellent climbers. Out in nature, they tend to nest in trees, and may find themselves in your home by walking along tree limbs that connect to your house.
They’re omnivores and have a wide range of food they can eat from seeds, fruits, fungi to a variety of invertebrates and vertebrates. They’ll also eat any food provided for cats and dogs, and food provided for some farm animals such as cows and chickens. They’re known to keep food in small caches to be consumed at a later time.
They carry and spread diseases such as leptospirosis and typhus, and their feces and urine also pose a health hazard. Roof rats are skittish and will avoid anything new introduced in the area, so it may be a while before they venture out to a trap or bait you’ve set up.
If you find either rodent in your house, get in touch with a pest control exterminator to have them removed.