Common Shrew Facts: Appearance Habitat, Evolution and Breeding

The common shrew, also known as the Eurasian shrew, is one of the most prevalent mammals throughout the Northern part of Europe, including Great Britain, but excluding Ireland. Scientifically the creature is known as Sorex Araneus.

Common/Eurasian Shrew

Appearance

The common shrew has small eyes, tiny ears, and a pointy face with a big nose. It is dark brown above, silver or grey below, and has chestnut-colored sides. It is slightly larger than the pygmy shrew, but its tail is only about half the body.

Habitat

Common shrews are located throughout the woodlands, grasslands, and hedgelands of Scandinavia, Britain, and Eastern Europe. Each shrew builds a home range of 440 to 750 yd² (370 to 630 m²). Males often extend the lines during the breeding season to locate females. Shrews are incredibly territorial and will defend their home from other male shrews. They make their nests under dense vegetation or underground.

Diet

Common shrews are always hungry. Their insectivorous and carnivorous diet consists of slugs, amphibians, insects, worms, spiders, and small rodents. Shrews need to consume more food than their body weight each day to survive. A shrew must eat every three hours to accomplish this goal. A shrew will die of starvation if it goes without food for more than seven hours. They do not hibernate in the cold because their stomach is too small to store adequate fat stocks, and because they have a short fasting duration.

Adaptable Evolution

Common shrews have evolved into a fantastic adaptation to sustain through the winter. Their skulls contract by nearly 25%, and their brains get smaller by as much as 32%. Their other organs also lose weight, and their spines get smaller. Their total body weight drops by about 20%. When spring arrives, they eat until they reach approximately their original size. Researchers believe that falling temperatures trigger their bodies to breakdown tissues and bones and absorb them. As temperatures start to rise with spring onset, their bodies rebuild the lost tissues and bones. This significantly reduces their food requirements and improves their chances of survival in the winter.

Additionally, Common shrews show three distinct seasonal phenotypes. However, these phenotypes have the same relative oxygen consumption despite varying temperatures. Shrews have bad eyesight and instead use their excellent senses of hearing and smell to find food.

Breeding

The common shrew breeding season lasts from April to August, but peaks during the summer months. After a gestation period of around 3-4 weeks, a female gives birth to a litter of four to eight babies. The young are weaned and independent within three weeks.

Young shrews often form a caravan behind their mother, each carrying its sibling’s tail in front with its mouth. Cute.

Common Shrew Fun Facts

  • They have one of the fastest metabolic rates in the mammal kingdom. The masked shrew’s heart pumps 800 times a minute, even quicker than that of the hummingbird.
  • When hunting for food, these animals can detect prey as deep as 15 cm underground.
  • Shrews are a terrible example if you wish to go on a diet. They eat 150% more than their own body weight daily.
  • Common Shrews are important for farms as they eat slugs and insects that harm crops.
  • Unlike most land animals who don’t crawl or jump, some species of shrew are indeed venomous. Shrew venom is not transferred into the wound by fangs, but by canals in the teeth. The venom contains various composites, and the contents of the American short-tailed shrew’s venom glands are enough to kill 200 mice by injection.
  • Shrews are easily frightened and will faint, jump, or drop dead at a sudden noise.

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