There are 33 species of shrews living in North America, according to the “National Audubon Society Field Guide to Mammals.” Classified as insectivores, shrews are tiny creatures -- some are less than 2 inches in length -- but they come with huge appetites. Shrews possess an incredibly high metabolism, translating into a constant hunt for food. If they fail to find for any length of time, they will die.
The lifespan of the typical shrew is short, with one reaching its second birthday considered old. Shrews engage in a constant struggle for fuel for a metabolism that sometimes precipitates heart rates as high as 1,200 beats per minute. Shrews require food night and day; going hungry for even a few consecutive hours can be fatal for a shrew. Many species must eat at least their own weight in food each day to survive. The long, pointed snout of the shrew features many sharp teeth, and its five clawed toes on each foot help it to subdue and tear apart its prey.
The Shrew Diet
The shrew kills and eats whatever it can, with a variety of creatures included in its diet. Shrews will devour earthworms, bugs, insect larvae and eggs, snails, centipedes, millipedes and an array of invertebrates. Shrews are capable of overpowering and killing the young of small mammals, as well as tiny as mice and voles. Fungi, plant matter and carrion help to round out a shrew’s diet. Some shrews hoard away food for later use.
What do shrews eat? Pretty much whatever they can including bugs, rodents, bird eggs, carrion and a variety of plants.
Competition for Food
When many species of shrews live in proximity to one another, competition for food increases drastically. However, in many cases, the different types of shrews focus on different kinds of targets, reducing competition and allowing the shrews to survive. For example, the arctic shrew eats mostly caterpillars, centipedes and beetles, along with their larvae. The masked shrew, sharing much of the same habitat, eats the same creatures, but also survives by eating slugs, snails and moths.
Shrews are beneficial creatures due to their diets, according to the South Carolina Department of Natural Resources. Shrews consume huge quantities of insects, with their diet of grubs and larvae preventing infestation of certain bugs harmful to crops. Shrews are certainly not immune to becoming part of another creature’s menu. Predators of the shrew include domestic cats and dogs, and wild animals like hawks, owls, snakes, coyotes, weasels and foxes.
- South Carolina Department of Natural Resources: Shrews
- International Union for Conservation of Nature: Blarina Brevicauda
- "National Audubon Society Field Guide to Mammals"; John O. Whitaker Jr., Revised 2008