It weighs about 5 grams, as much as a quarter. The shrew
is so small that many specimens in our collection were brought in by
entomologists using beer bottle pitfall traps to catch beetles. Least
shrews are tiny enough to slip through the neck of the bottle and drown
within. Least shrews are common, nocturnal and warm-blooded. Five grams
is not a very good size for being warm-blooded because you have a lot
of outsides (to lose heat) compared to insides (to make heat). If you
are going to be tiny and warm-blooded you will need a lot of fuel (food).
Least shrews must eat as much as their own body weight every day, particularly
in cold weather.
While eating is paramount they do other things, too.
They have as many as three litters each year with two to seven young
per litter. Babies are born, weaned and on their own in three weeks.
While still with their mother the babies follow her closely by clinging
to her tail (or that of a littermate).
They may spend their whole lives in less that an acre
in most Kansas habitats and must be ever vigilant for predators in the
form of snakes and raptorial birds. Mammalian carnivores (perhaps your
cat) often catch and kill these tiny creatures but rarely eat them.
They reportedly taste bad, but I don't know anyone
who has conducted the research to find out.
Thor Holmes
Collection Manager for Mammals
Natural History Museum
