The Star-nosed Mole is a small North American mole found in eastern Canada and the north-eastern United States. It lives in wet lowland areas and eats small invertebrates, aquatic insects, worms and molluscs. It digs shallow surface tunnels, often, these tunnels exit underwater. The Star-nosed Mole is covered in thick blackish brown water-repellent fur and has large scaled feet and a long thick tail, which appears to function as a fat storage reserve for the spring breeding season. Adults are 15 to 20 cm in length, weigh about 55 g, and have 44 teeth.
The mole's most distinctive feature is a circle of 22 mobile, pink, fleshy tentacles at the end of the snout. These are used to identify food by touch, such as worms, insects and crustaceans.
The Star-nosed Mole mates in late winter or early spring, and the female has one litter of typically 4 or 5 young in late spring or early summer.
Predators include the Red-tailed Hawk, Great Horned Owl, various skunks and mustelids, and even large fish.
The incredibly sensitive nasal tentacles are covered with almost one hundred thousand minute touch receptors known as Eimer's organs. Because the Star-nosed Mole is functionally blind, it had long been suspected that the snout was used to detect electrical activity in prey animals, though there is little, if any, empirical support for this contention. It appears the nasal star and dentition of this species are primarily adapted to exploit extremely small prey items. A report in the journal Nature gives this animal the title of fastest-eating mammal, taking only 120 milliseconds to identify and consume individual food items. Its brain decides in the ultra short time of 8 ms if a prey is comestible or not. This speed is at the limit of the speed of neurons. By observation through video camera it is decovered that the Star-nosed Mole can smell under water. It sniffs through the water by quickly reinhaling the air bubbles that leave their nostrils.
The star of tentacles is formed in a unique way so far not seen other places in the animal world. Instead of growing in the same way fingers grow outward on a hand, they start as swellings on the face around the nose, and some days after birth they break free and move forward in the same way a banana is peeled.