Star-Nosed Mole Fact Sheet | Nature

Star-Nosed Mole (Condylura cristata): a small semiaquatic mole.

Size and Weight:

They measure 6-8 inches and their is tail 2.6-3.4 inches. On average, they weigh 0.12 pounds.

Appearance:

Set aside the 22 fleshy pink tentacles that form the “star” on the nose of this mole, and it remains an odd-looking creature. The mole, which is covered in dense, blackish brown, water-repellent fur (ideal for its life in moist, mucky soil), has broad, scaly feet with large claws for fast digging, a stout cylindrical body, and a long thick tail that swells with fat to three to four times its normal size during the winter. The males’ testes also expand during the mating season (once yearly, roughly mid-March to April, although females may breed a second time if their first litter is unsuccessful), and can reach nearly nine percent of the animal’s entire body weight.

Appropriate to its life largely underground, the star-nosed mole is essentially blind. However, thanks to the tentacled star, the mole has perhaps the best sense of touch of any mammal in the world. Each of the .03-.16 inch-long (1-4 mm) tentacles is covered by about 25,000 minute touch receptors, known as Eimer’s organs. The receptors come in three varieties, including one that senses the microscopic texture of objects, believed to be unique to the mole. The tentacles, which are also thought able to detect the minute electrical fields produced by aquatic animals as they move through water, move with lightning speed, and can touch as many as 12 objects per second. This allows the mole to rapidly identify and consume small prey, which consist of worms (including leeches), aquatic insects like dragonflies and damselflies, and the occasional terrestrial insect, mollusk, and small fish.

Photo: US National Parks Service/ Wikimedia Commons

Diet:

Earthworms and aquatic insects are the primary foods, but it also eats snails, crayfish, small amphibians, and fish. The star-nosed mole blows and re-inhales air bubbles underwater as fast as five to ten times per second to track prey.

Habitat:

Star-nosed moles are found in a variety of habitats with moist soil, including woods, bogs, marshes, and fields.

Geography:

Native to eastern North America, from Quebec and Newfoundland, south to at least Virginia, and west to North Dakota. Also found throughout the Appalachian Mountains

Breeding:

Mating begins in mid-March to April with young being born in late April through mid-June. Females produce one litter of offspring per year like other moles. Litters ranging in size from 2 to 7 (average 5) young are born after a 45 day gestation period. The pale pink, blind, and hairless newborns grow at a rapid rate. Eyes, ears, and the tentacles of the star become functional at 2 weeks and the young are ready for weaning after 3 weeks.

Social Structure:

Like many other moles, star-nosed moles dig networks of tunnels through moist soil. They use these shallow surface tunnels foraging. Unlike other mole species, they do not dig deeper burrows for protection in the winter.

Star-nosed moles are more social than other mole species. While most moles are territorial and live alone, star-nosed moles have been observed living in small family groups, particularly during the breeding season. It is not known if more than one mole will share a network of tunnels, other than paired males and females during the breeding season.

While their primary sense is touch, using their unique star-shaped nose, they may also communicate through scent markings and possibly vocalizations or other subtle behaviors.

Lifespan:

Their lifespan in the wild is unknown. However, based on female reproduction rates, their lifespan is likely 3 to 4 years. In captivity, some star-nosed moles have lived 2 years.

Threats:

Star-nosed moles are relatively adaptable and not currently considered endangered, but they do face several threats in their wetland and forested habitats. These threats include habitat destruction, pollution and the impacts of climate change.