Shrew

Shrews in Madison, Wisconsin

Shrews are tiny mammals that belong to the order Eulipotyphla, which means “truly fat and blind”. They are not rodents, but insectivores, meaning they feed mainly on insects and other invertebrates. They are often mistaken for mice, but they have some unique characteristics that set them apart.

How to Identify Shrews

Shrews have velvety dark brown or gray fur and a pointed, mobile snout with red-tipped teeth. They measure about 3-4” long, including their tail and weigh between 1-2oz. Their eyes are small, and their ears are hidden by fur. Shrews have sharp, spike-like teeth, not the familiar gnawing front incisor teeth of rodents. Some shrew species have venom that can paralyze or kill their prey.

Shrews have five toes on each foot and long claws for digging. They have a high metabolic rate and a fast heartbeat. They need to consume 200 to 300% of their body weight in food each day to survive. A shrew must eat every 2 to 3 hours to achieve this goal. If a shrew doesn’t eat every few hours, it will die.

Shrews have a keen sense of smell and hearing, but poor vision. They use echolocation to navigate and locate prey. They make high-pitched squeaks and clicks that bounce off objects and return to their ears.

Shrews have a distinctive corkscrew-shaped dropping that is 1/6-1/4” in length and deposited in piles in a latrine area.

Shrews Lifecycle

Shrews have a short lifespan and a high reproductive rate. Their gestation period is 24 to 25 days and they can breed from April to September, but peaks during the summer months. A female has 2-4 litters each year, with an average of 5-7 pups each.

The pups are born blind, hairless, and helpless. They are weaned and independent within 22 to 25 days. It takes 2-3 months to reach sexual maturity. Shrews have a life span of approximately 14 months.

Common shrews have evolved adaptations to survive through the winter. Their skulls shrink by nearly 20% and their brains get smaller by as much as 30%. Their other organs also lose mass, and their spines get shorter. As a result, total body mass drops by about 18%. When spring returns, they grow until they reach roughly their original size.

Shrews Lifecycle

Shrews are active year-round and mostly nocturnal. They live in woodlands, grasslands, gardens, and areas abundant in food sources. They nest in burrows or under dense vegetation. They use existing tunnels made by moles or voles or dig their own with their sharp claws.

Shrews feed on insects, slugs, spiders, worms, amphibians, and small rodents. They are insectivores but will feed on seeds, roots, and vegetable matter if needed to survive. They kill more prey than they can eat and store the excess in their burrows for later consumption.

Shrews are territorial and aggressive. They will fight with other shrews or predators that invade their space. They can defend themselves with their venomous bite, which can cause pain, swelling, and numbness in humans.

Shrews rarely inhabit structures. When they do, it is usually by mistake and due to easy entry through an open door or large gap around the exterior.

How to Control Shrews

Shrews can be beneficial for controlling insect pests, but they can also cause problems for humans and pets. They can damage plants by eating roots, bulbs, seeds, or fruits. They can also transmit diseases.

The best way to control shrews would be to give a professional pest control service a call, like Kwik Kill Pest control. We have several services available to combat the shrew issues you are seeing in your business or home.

Kwik Kill Services to Control Shrews

Additional Resources

https://hles.unl.edu/shrew-0
http://www.biokids.umich.edu/critters/Blarina_brevicauda/
http://www.biokids.umich.edu/critters/Blarina_carolinensis/