Sorex – Long-tailed shrews

A remarkable group of tiny insect-eating mammals that thrives across Europe, Asia, and North America. These shrews get their common name from their long tails, which usually measure more than half the length of their body—an important feature that distinguishes them from other types of shrews with shorter tails. Their small size, generally just a few grams in weight, and elongated tails and pointed snouts make them instantly recognizable to zoologists and naturalists.
What makes long-tailed shrews stand out, beyond their tail length, is their incredibly fast metabolism and constant need for food. Like other shrews, they must eat almost nonstop to survive, consuming up to their own body weight or more in insects and small invertebrates each day. Many species in Sorex also show a fascinating seasonal adaptation known as Dehnel’s phenomenon—in winter, their skulls and organs shrink, reducing their energy demands during the toughest months. Come spring, these body parts regrow to normal size. This ability is almost unique in mammals and gives Sorex shrews an edge in surviving harsh climates. In addition, their long tails help with balance and maneuverability as they dart through dense vegetation, tunnels, and leaf litter in search of prey.

Long-tailed shrews are generally solitary and highly territorial, marking their ranges with scent glands and defending them vigorously from other shrews. Their eyesight is poor, but they make up for it with an excellent sense of smell and sensitive whiskers that help them detect prey in the dark. Some species can even use primitive echolocation, emitting tiny sounds to sense their environment in low light—similar to bats, though far less sophisticated. Most species live short, fast-paced lives, typically surviving no more than a year or two in the wild. Despite their small size, they are fierce hunters, preying on insects, worms, and sometimes even small vertebrates like frogs or baby rodents.