This week’s #SpeciesOfTheWeek is a secretive mammal, the northern short-tailed shrew (Blarina brevicauda). With a diminutive size of just 10 to 14 cm, it’s already easy to miss, and its habit of tunnelling underground or through the leaf litter makes spotting one a rare occurrence. Despite the small size, the northern short-tailed shrew is actually the largest shrew in North America. The short-tailed shrew can be differentiated from long-tailed shrews (Sorex spp.) by the fact that its tail makes up less than 25% of its body length. The short-tailed shrew is particularly unique, as it is the only venomous mammal in North America. The shrew’s saliva contains a neurotoxin that kills or paralyzes its prey, allowing it to take down large prey like earthworms, voles, snails, mice and salamanders. Shrews have a high metabolic rate and need to eat up to three times their body weight every day, so they will cache food for later consumption. These tiny terrors can be found in a range of habitats with leaf litter or thick plant cover. Keep an eye on the ground when hiking through the park, and you might catch a glimpse of this cool mammal!