Blarina

Blarina is a genus of small, stocky shrews in the family Soricidae, commonly known as short-tailed shrews. It comprises two living species native to North America: the northern short-tailed shrew (Blarina brevicauda) and the Carolina short-tailed shrew (Blarina carolinensis).

Description

Members of Blarina are among the larger shrews by body mass, with dense fur that ranges from brownish gray to almost black. They have very short tails, broad snouts, and robust bodies. Like other shrews, they possess sharp incisor teeth and a high metabolic rate.

Venom

Blarina species have venomous saliva produced by submandibular glands, which helps subdue prey; this trait is unusual among mammals and has been the subject of research.

Ecology and behavior

They are insectivorous and opportunistic predators, feeding on insects, worms, snails, and small vertebrates. Their high metabolic rate requires frequent feeding. They are primarily nocturnal or crepuscular and forage through leaf litter, under logs, and in soil.

Reproduction

Breeding occurs in spring and summer, with litters typically of several young. Gestation is short, and young are weaned within a few weeks.

Distribution and habitat

Found across eastern and central North America, from Canada to the southern United States. They inhabit deciduous and mixed forests, wetlands, and moist grasslands, often favoring damp leaf litter and rotted logs.

Conservation

Blarina species are widespread and not considered threatened overall, though local populations may be affected by habitat loss, pollution, and pesticide exposure.