The Northern Short-tailed Shrew, Blarina brevicauda, is a large shrew found in central and eastern North America from southern Saskatchewan to Atlantic Canada and south to Nebraska and Georgia. At one time, this species and the Southern Short-tailed Shrew, B. carolinensis, were considered to be a single species.

It is slate grey in colour with light underparts. Its body is about 10 cm in length including a 2 cm long tail. They weigh about 21 g, about the same as a house mouse.

These animals are found in damp hardwood and coniferous forests and wet open areas.

They eat insects, earthworms, snails, small rodents and plant material. These shrews dig through leaf litter and can also tunnel in moist ground. They have scent glands that release a musky secretion which repels some predators; males also use scent to mark their territory.

Mating begins in early spring and may occur until late fall. The female has 2 or 3 litters of 5 to 7 young in a nest in a tunnel or under a fallen log.

Glands in their mouth contain a neurotoxin which allows them to immobilize larger animals such as snakes and birds.