Moles

Common Name:

Moles

Scientific Name:

Talpidae family

Type:

Mammals

Diet:

Omnivore

Average Life Span:

Two years in most species

Size:

Two to nine inches, depending on species

Weight:

Under half an ounce to more than half a pound, depending on species

What is a mole?

Moles include dozens of species of small, burrowing animals found all over the world. Known for their tunneling prowess, moles are pint-size predators that create elaborate networks of tunnels and pathways through leaf litter, vegetation, and soil.

Consistent with a life spent underground, mole eyes are tiny and lack external ears, which could fill up with dirt. Mole bodies tend to be cylindrical, with powerful shoulders and broad, shovel-like hands, all of which helps them ply through the substrate as if it were water.

Speaking of water, some mole species are surprisingly good swimmers. For example, the star-nosed mole inhabits wetlands in northeastern North America, where it uses its curious-looking, namesake appendage to rapidly detect and devour invertebrates. (Inside the bizarre life of the star-nosed mole, world’s fastest eater.)

Because of their cryptic nature and subterranean lifestyle, moles are some of the least-studied mammals. They are also frequently misunderstood.

For instance, many people think all moles are blind or even without eyes entirely. This is not true: All mole species have eyes, though their vision tends to be quite basic. Scientists believe moles are colorblind and nearsighted, but that their eyes are exceptionally good at detecting light.

A number of other small animals have evolved similar body shapes and behaviors to moles, sometimes earning them common names that lead to confusion. This includes mammals, such as golden moles (more closely related to tenrecs, which are small mammals native to Madagascar) and mole rats (which are rodents), as well as insects such as mole crickets and crustaceans like mole crabs. However, none of these animals are actually moles of the family Talpidae.

However, animals that are members of the Talpidae or mole family include desmans, which look like more typical moles but have webbed paws for swimming rather than digging, and shrew moles, which spend more time foraging above ground than their relatives.

Habitat and diet

While most people associate moles with dirt, these creatures can be found in lots of different habitats, including grasslands, sand dunes, woodlands, swamps, and wetlands. Mole species inhabit every continent except South America and Antarctica.

Many mole species possess surprisingly large home ranges, at least when compared with other small mammals. For example, a male eastern mole (Scalopus aquaticus) in North America was recorded as inhabiting more than two acres.

Moles are experts at excavating soil, which they discard at the surface in easily-identifiable “molehills.” But these tunnels are more than just holes in the ground. Within their complex, moles also create special rooms, such as bedding and birthing chambers.

Tunnels also serve as traps for prey, and moles are known to race up and down their two-inch-tall corridors searching for food.

Moles are sometimes classified as insectivores, but they are actually omnivores. Gut content studies have found that the animals ingest some vegetable matter, as well as mycorrhizal fungi. Arthropods, especially insects and grubs, make up a large part of their diet. But most moles specialize in eating earthworms.

In fact, moles eat so many earthworms, they have developed several advanced methods for preparing them. Grabbing the invertebrate with its front paws, a mole will actually squeeze the worm along its length to remove debris from the outside and push out any accumulated dirt in the worm’s gut. In his book, The Life of Mammals, David Attenborough likened the process to squeezing toothpaste from a tube.

When food is plentiful, moles will also sometimes bite the head of the earthworm, which incapacitates it and keeps it from crawling away. Then the mole will stash its prey in a storeroom, along with any other earthworms it has caught recently.

Threats to survival

Thanks to a life spent out of sight, moles have few natural predators. However, hawks, owls, red and gray foxes, coyotes, weasels, raccoons, skunks, pine martens, and even pet dogs and cats will all prey upon moles when given the chance.

In many areas, humans are the biggest threat to mole survival. Homeowners often trap or poison the animals because of the perceived threat to their lawns. And while moles don’t target plant roots like some believe, many people consider their tunnel systems to be a nuisance. Development projects, agriculture, and other habitat changes can also affect mole populations.

Conservation

Most mole species are not of conservation concern, but some are thought to be in decline.

For instance, the small-toothed mole of Vietnam and China was classified as critically endangered in 1996, but is now considered “data deficient,” which means scientists don’t have enough information to know how the species is faring.

Likewise, the International Union for Conservation of Nature considers the Russian desman to be endangered, thanks to the widespread use of fishing nets across its range. As a result, the species has been given protections in some parts of its range. Reintroduction efforts have also been attempted.