Star-Nosed Mole Facts: 18 Fascinating Facts About This Super-Sensitive Mammal

Quick Answer: The star-nosed mole (Condylura cristata) is a semi-aquatic mammal native to eastern North America. Its nose is surrounded by 22 fleshy appendages covered in specialized touch receptors called Eimer's organs. This sensory system helps it identify prey with extraordinary speed, while its ability to blow and re-inhale air bubbles underwater helps it detect scents in aquatic environments.

An illustrative depiction of a star-nosed mole in its wetland habitat, highlighting its 22 fleshy nasal appendages, specialized touch organ, and adaptations for finding prey. Illustration: The Pader.

At first glance, the star-nosed mole looks as if it has a tiny pink star growing from its face. That unusual structure is not decorative, and it is not primarily a tool for smelling. It is one of the most specialized touch organs known in mammals.

This small, semi-aquatic mole can explore its surroundings with remarkable precision, identify and eat tiny prey in fractions of a second, and even use air bubbles to detect smells underwater. Its strange appearance reflects a set of adaptations that help it find food in dark tunnels and wet habitats.

18 Fascinating Star-Nosed Mole Facts

1. Their Nose Has 22 Fleshy Appendages

The star-nosed mole's most recognizable feature is a ring of 22 pink, finger-like appendages around the end of its snout. These projections are arranged in a star shape, with 11 on each side.

Unlike ordinary facial whiskers, the appendages form a highly specialized sensory surface. The mole repeatedly moves this star against objects as it investigates its surroundings and searches for food.

2. The Star Is a Touch Organ, Not a Smelling Tentacle

Despite its unusual appearance, the star's main role is touch. Its appendages are densely covered in microscopic sensory structures that respond to physical contact.

This allows the mole to detect and investigate objects in dark burrows, leaf litter, and underwater environments where vision is limited or less useful. Smell is also important to the animal, but it works through a different sensory pathway.

3. Their Nose Contains Thousands of Eimer's Organs

The sensory structures covering the star are called Eimer's organs. Each contains specialized cells and nerve endings that help detect mechanical stimulation, including subtle details of the surfaces the mole touches.

Studies have reported roughly 25,000 Eimer's organs on the star, although published counts and descriptions can differ depending on the study and how the structures are measured. Together, they create an exceptionally dense tactile sensing surface.

4. One Part of the Star Acts Like a Touch-Based Fovea

The star-nosed mole does not use every appendage in exactly the same way. Research has identified a particular appendage on the lower side of the star that is preferentially used to examine objects of interest.

Scientists compare this arrangement to a visual fovea—the part of a human eye that provides especially detailed vision. The mole uses its specialized tactile region to investigate an object after the rest of the star has helped locate it.

5. They Can Identify and Eat Prey in Just 120 Milliseconds

One of the most remarkable findings about this mammal is its feeding speed. In research published in Nature, star-nosed moles identified and consumed some prey items in as little as 120 milliseconds.

The average handling time in that study was longer, about 227 milliseconds. The fastest observation is an exceptional recorded result, not the time required for every meal.

6. They Are Known as the Fastest-Eating Mammals

The star-nosed mole's feeding performance has earned it recognition as the fastest-eating mammal known. Its specialized nose lets it rapidly assess whether a tiny object is prey and then move on to the next potential meal.

This speed is useful because the mole often feeds on small invertebrates. When individual prey items provide only a modest amount of energy, quickly finding and handling many of them can make a meaningful difference to the animal's feeding efficiency.

7. Their Nose Moves Constantly While They Forage

When searching for food, star-nosed moles repeatedly sweep and press their star against nearby surfaces. Researchers have observed nose movements at rates of approximately 10 to 15 contacts per second during foraging.

These rapid movements allow the mole to sample many small areas of soil or other surfaces. The sensory information helps it determine where an object is and whether it is worth investigating further.

8. Their Sensory System Helps Them Find Tiny Prey

Star-nosed moles eat a variety of small animals, including earthworms, aquatic insect larvae, leeches, snails, and other invertebrates. They may also consume small fish and other available aquatic prey.

Their specialized nose is particularly useful when prey is difficult to see. Instead of depending on a clear visual image, the mole can use touch to detect the location and surface features of a potential meal.

9. They Can Sniff Underwater Using Air Bubbles

Most land mammals cannot simply inhale water to carry odor molecules to their olfactory system. The star-nosed mole uses an unusual workaround when searching for food underwater.

It blows small air bubbles onto an object or scent trail and then re-inhales the bubbles. The returning air can carry odor molecules back toward the nose, allowing the mole to investigate smells in an aquatic environment.

10. Underwater Sniffing Is Different From Touching With the Star

The mole's underwater behavior involves two separate senses. Its nasal star detects objects through physical contact, while bubble sniffing helps it sample chemical cues associated with smell.

These abilities complement each other. Touch can help the mole inspect a nearby object, while olfaction can provide additional information about its surroundings. Neither ability means the mole breathes underwater like a fish.

11. They Are Semi-Aquatic Mammals

Unlike many other moles, star-nosed moles regularly use aquatic environments as part of their lives. They can forage in shallow water, swim, and dive while searching for prey.

Their broad forefeet help with digging and swimming, while their dense fur and body shape support movement through wet habitats. They still depend on air to breathe, as other mammals do.

12. They Prefer Wet Soil Near Water

Star-nosed moles are commonly associated with marshes, bogs, wet meadows, streambanks, and other places where the soil remains moist. Such habitats provide suitable ground for tunnels and access to abundant small invertebrates.

Some of their tunnels connect with aquatic areas, giving them opportunities to search for food both in soil and in water. Their habitat preferences help explain why they are more closely associated with wetlands than many other mole species.

13. They Live in Eastern North America

The star-nosed mole is native to eastern North America, including parts of the northeastern United States and southeastern Canada. Its distribution includes a range of wet habitats rather than one single type of forest or marsh.

Local populations depend on suitable soil, moisture, and food availability. The species' ability to forage both underground and in water helps it use habitats that may be less suitable for other moles.

14. They Are Active During Both Day and Night

Star-nosed moles can be active during the day and at night. Their activity is not restricted to a single daylight schedule, and they spend much of their time moving through tunnels or searching for food.

Because they live in concealed burrows and often forage in wet soil or water, people may rarely see them even in areas where they occur. Their unusual nose is much more likely to reveal their identity than a brief glimpse of their body.

15. Their Diet Includes Both Land and Aquatic Prey

Earthworms and other soil invertebrates are important foods, but the star-nosed mole is not limited to prey found underground. It also consumes aquatic invertebrates such as insect larvae and leeches.

Depending on local conditions, its diet can include crustaceans, mollusks, and small fish. This variety allows the mole to take advantage of food sources in the moist soil and water around its habitat.

16. They Have Powerful Front Feet for Digging

Like other moles, the star-nosed mole has broad forefeet with strong claws that help it move through soil. These limbs are well suited to digging tunnels and searching for invertebrates beneath the surface.

Their forefeet are also useful in aquatic settings, where they assist the mole as it moves through water. This combination of digging and swimming abilities is consistent with its semi-aquatic lifestyle.

17. Females Usually Produce One Litter Each Year

Star-nosed moles generally produce one litter per year, with reports commonly describing about three to seven young. Breeding takes place during the spring and summer period, though timing varies with location and environmental conditions.

The young are born in protected nests within the burrow system. As with many small mammals, much of their early development occurs out of sight, so detailed observations of their lives in the wild can be difficult.

18. Their Strange Nose Helps Them Fill a Specialized Ecological Role

The star-nosed mole's sensory system is more than an unusual physical feature. It allows the animal to find and consume small prey rapidly in wet soil and aquatic habitats, where other predators may search differently.

By specializing in detecting and handling tiny prey, the mole can exploit food sources that reward rapid foraging. Its unusual nose is a clear example of how natural selection can shape a sensory system around the demands of an animal's environment.

Why This Is Amazing

The star-nosed mole demonstrates that an animal does not need exceptional eyesight to explore its world with extraordinary precision. Its nose combines thousands of touch receptors, rapid movement, and specialized processing in the brain to locate and assess prey at remarkable speed.

Its underwater sniffing behavior adds another layer to the story. By reusing air bubbles to carry scent information, this mammal shows how a land-based sense can be adapted for use in water. These are distinct adaptations, but together they help the mole exploit a wetland environment.

Frequently Asked Questions About Star-Nosed Moles

What are the 22 tentacles on a star-nosed mole used for?

They form a specialized tactile organ. The appendages are covered with Eimer's organs that help the mole detect physical details and locate prey.

How fast can a star-nosed mole eat?

Research recorded prey identification and consumption in as little as 120 milliseconds, with a mean handling time of about 227 milliseconds in the reported study.

Can star-nosed moles smell underwater?

Yes. Researchers observed them blowing air bubbles onto objects or scent trails and then re-inhaling those bubbles, helping carry odor molecules back toward the nose.

Where do star-nosed moles live?

They live in eastern North America, especially in moist habitats such as marshes, bogs, wet meadows, and streambanks.

What do star-nosed moles eat?

Their diet includes earthworms, leeches, aquatic insect larvae, snails, and other invertebrates. They may also eat small fish and other aquatic prey.

Takeaway

The star-nosed mole is a small mammal with an extraordinary set of adaptations. Its 22-part nose helps it detect prey through touch, its feeding system can work in fractions of a second, and its underwater sniffing technique lets it gather scent information using air bubbles.

Rather than being a strange-looking animal with a single unusual feature, it is a specialist whose sensory system, feeding behavior, and wetland habitat fit together. The star-nosed mole shows how evolution can produce remarkable solutions to the everyday challenge of finding food.

Explore This Animal's World

• Amazing Animal Adaptations for Extreme Environments
• How Animals Sense the World: Animal Senses Explained
• Remarkable Animal Behavior
• How Animals Use Smell to Find Food and Avoid Danger

More From The Pader

Sources and Further Reading

• Catania, K. C. (1995). Structure and innervation of the sensory organs on the snout of the star-nosed mole. Journal of Comparative Neurology. Research on the 22 appendages and Eimer's organs.
• Catania, K. C., & Remple, F. E. (2005). Asymptotic prey profitability drives star-nosed moles to the foraging speed limit. Nature. Research on rapid prey handling and feeding speed.
• Catania, K. C. (2006). Underwater 'sniffing' by semi-aquatic mammals. Nature. Research describing bubble-assisted olfaction in star-nosed moles and water shrews.
• Maine Department of Inland Fisheries and Wildlife. Star-Nosed Mole: Species Information. Overview of habitat, diet, characteristics, and reproduction.
• Natural History Museum. Why do star-nosed moles have a 'hand' on their face? Background on sensory anatomy, diet, and feeding speed.