Field Guide/Mammals/Arctic Shrew

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Sorex Arcticus (Arctic Shrew)
Family: Shrew
Size: • Total length:

o 3.9 to 4.9 in (100 to 125 mm)

• Tail length:

o 1.4 to 1.8 in (36 to 45 mm)

• Weight:

o .18 to .47 oz (5.3 to 13.5 g) [1]
Description: This particular species is similar to the size of a mouse and is a medium size compared to other shrews. The back of this animal is a darker brown. The sides are light brown. The stomach has a more gray like brown color. The tail starts out dark and then ends in a dark brown.[1]
Similar Species: • The tri colored body is what distinguishes this from others like it. This shrew is also larger than the others in its family. • Another distinguishing trait is that its tail has dual colors unlike others in its family.[2]

Range: • This species ranges from the Arctic Circle as far down as the northern part of the United States.

• They go as far as east as Quebec and up to the Atlantic coastline. They go as far west as southern Yukon.

• They are typically found in Minnesota, North and South Dakota, Michigan, and Wisconsin.[3]
Habitat: • This species prefers to live in moist, open areas. Particularly in Minnesota they favor living in marshes that surround rice lakes. • However, this particular species of shrew is also able to adjust to other habitats depending on what part of the country this animal is found.[2]
Diet: • These animals are insectivorous.

o The types of insects that this animal eats in particular are grasshoppers, larch sawflies, and some aquatic insects as well.

o Generally they forage in the ground for their food but have also been known to climb plants to get their food.[3]
Activity: • These animals are mostly active at night and are considered to be nocturnal. They also spend part of their time awake during the day making them diurnal as well.[3] They are typically not active between the hours of 6:00 AM and 10:00 AM.[2]

• When they are awake they tend to move quite quickly. During periods of inactivity they generally lay on their side or stomach with their heads tucked under.

• This species is also a very solitary animal that does not survive well with others.[3]

Reproduction: • This species is generally promiscuous in its mating. Males often move farther away from their homes than the females to mate.[3]

• Females typically have 1 or 2 litters in their lifetime. It is characteristic in Minnesota that the first litter is born sometime between April to late August with most occurring in June. • Gestation lasts around 13 to 21 days. Lactation typically is 20 to 24 days. • Weaning lasts about 5 to 6 weeks. • The average litter size of this shrew is 6.8 per litter.

• The offspring reach sexual maturity at the age of 12 months.[4]
Lifespan: • The lifespan of this animal is typically 18 months.[3]

Notes: In the wilds of Minnesota it will be quite hard to find this tiny animal as they are only about 4 inches long. Oddly they are considered to be a large size compared to other shrews in the family. To distinguish this shrew from others you will have to look at the coat and tail of it. The coat is tri colored and the tail gets darker as it comes to the end. This animal generally eats insects and will go to great lengths to get them including climbing large plants. It will be easy to find these animals during the day but they can especially be found at night searching for food. In Minnesota it would be most easy to find them in wet land areas such as marshes and swamps. This animal is quite adaptable in that it can adjust to a variety of climates making it a great animal for Minnesota. These animals are very solitary in nature. In captivity when 2 of them are together one always suspiciously dies with no signs of any sort of fight between them.
The northern short tailed shrew is very similar to the arctic shrew with the same body type and similar size

  1. a b "Arctic Shrew-Sorex Arcticus", Montana Field Guide,, retrieved September 23, 2012 
  2. a b c Lariviere, Serge (1999), "Sorex Arcticus", Mammalian Species (608): 1–9,, retrieved September 23, 2012 
  3. a b c d e f Seto, Stephanie (2006), "Sorex Arcticus, Arctic Shrew", Animal Diversity Web,, retrieved September 23, 2012 
  4. Clough, Garrett (1963), "Biology of the Shrew", American Midland Naturalist (69): 69–81,, retrieved September 23, 2012