It is the largest and most robust of Pennsylvania shrews. They frequent the top few inches of soil and leaf litter, digging their own tunnels or using those of mice, voles and other small mammals. They burrow through the snow in winter. Home range is a half-acre to an acre. Active day and night, short-tails eat insects, worms, snails, salamanders, small snakes, songbirds, mice, voles, other shrews, carrion and vegetable matter.
Individuals cache food in small chambers in their burrows.
The short-tailed shrew has poor eyesight, a fair sense of smell and keen hearing and touch. It possesses poisonous saliva but lacks an efficient injection system, so the toxin must get into a prey animal through cuts caused by the shrew's sharp teeth. The toxin slows down or kills warm-blooded prey. Blarina brevicauda weaves dry plant materials and hairs into two types of nests, a resting nest and a larger mating structure, beneath logs, stumps, rocks and debris. Two or three litters may be raised per year.