Some animals may seem strange to us, either with their habits or their physic. The strangest animal often seems to us to come from afar. But, there is a curious looking animal that lives in North America, the star-nosed mole. It is part of the Talpidae family, like the better known Hairy-tailed mole. The star-nosed mole is not impressive for its size. It measures a mere 12 centimeters and weighs 55 grams on average. Its coloration is not spectacular either, since it is all gray. But what about its nose!
Its nose is what makes it special. Just like its name implies, the star-nosed mole as a round nose lined with 22 appendages. These appendages are arranged symmetrically, with 11 on each side of the snout. This particular nose is very sensitive. As it moves, the mole hits the ground with its nose as quickly as possible, about 10 to 12 times per second! This technique, which seems random, is very effective, since with each contact, 25,000 ultra-sensitive mechanoreceptors send information to the brain via 100,000 nerve fibers. That is 6 times more tactile sensors than the human hand. Moreover, its nose is the most sensitive epidermal area in mammals, which earned it a Guinness World Record in 2013.
This nose also allows it, just like us, to smell. But again, the mole does not do things like others. It is a semi-aquatic animal that hunts, among other things, in water. Although it does not breathe underwater, it is able to smell. It produces air bubbles, which it sucks through the nose. To date, there are only two mammals that have this ability to smell underwater, the star-nosed mole and the American water shrew, also present in North America.
Such a nose is of great use to the mole, which is practically blind. Its eyes only distinguish variations in light intensity. Like its cousin the Hairy-tailed mole, the star-nosed mole digs galleries in which it hunts its prey. Its front paws are wide and end with large shovel-shaped claws. The corridors of the galleries are between 3 and 6 centimeters wide. The tunnel system can extend 300 metres. It must be said that the mole can live in small colonies. The nose is useful in this situation too, since it allows the mole to distinguish other members of the group.
Another particular adaptation is the mole’s fur, that can be smoothed in all directions, which allows it to retreat even in narrow places. It can therefore move quickly to catch its prey. Prey it devours at lightning speed. In less than 230 milliseconds, or less than a quarter of a second, it touches, identifies and devours its prey. It is 14 times faster than the other moles, which even earned him another Guinness World Record!
Its main preys are earthworms, aquatic insects, molluscs and crustaceans. And it eats a lot of them! It has a very fast metabolism, which requires a lot of energy. It eats so much, the equivalent of its weight, every day. It is as if an average human would eat 85 whole chickens a day. To do this, it is active year-round, day and night. It life does not depend on photoperiod. In order to make prepare for periods when it has less time to eat, such as reproduction, it accumulates fat in his tail. The tail is also useful when the mole swims, since it serves as a rudder.
The swimming abilities of the mole is the last fascinating element of the animal. It is the most aquatic mole in Quebec. It chooses the wet grounds near the water to establish its nest. Although sheltered from predators when in its tunnels, it spends considerable time on the surface or in the water in search of food. It can dive of more than 45 seconds without breathing and swim for almost an hour.
With all these peculiarities, the star-nosed mole is certainly one of the strangest animals in Quebec. Nevertheless, it is rather rare to observe it. You really have to know your biology and be patient to see the tip of its starry nose.
Author : Stéphanie Bentz, biologist in charge of education
Sources :
Prescott, Jacques et Pierre Richard. (2013). Mammifères du Québec et de l’Est du Canada (3e édition). Waterloo, Québec : Éditions Michel Quintin.
National Geographic. L’étrange vie du condylure étoilé, seule taupe capable de chasser sous l’eau [En ligne] https://www.nationalgeographic.fr/animaux/letrange-vie-du-condylure-etoile-seule-taupe-capable-de-chasser-sous-leau (Page consultée le 8 novembre 2023)
Gouvernement du Québec. Pleins feux sur… l’Halloween et le condylure à nez étoilé [En ligne] https://mffp.gouv.qc.ca/jeunesse/halloween-condylure-nez-etoile/ (Page consultée le 8 novembre 2023)
Guepe. Toucher avec son nez : le condylure [En ligne] https://www.guepe.qc.ca/blogs/toucher-avec-son-nez-le-condylure (Page consultée le 8 novembre 2023)