Bats in Our Backyard: Meet Minnesota’s Marvelous Mini Mammals
Name _______________
5.2 Bat Math
DIET
FAMILY LIFE
BEHAVIOR
1.) Twenty little brown bats
live in a bat house colony.
If one bat can catch as
many as 1,200 mosquitoes
in one hour, how many
mosquitoes can the entire
colony catch in two hours?
5.) Some kinds of bats have
one or two babies (pups)
every year. If a tri-colored
bat has pups every year for
16 years, having one pup
half the time and two the
other half, how many pups
would she have?
9.) Some kinds of bats are
born in spring. They grow
quickly, gaining 18% of
their birth weight each day.
If a pup weighs 3 grams at
birth, how much would it
weigh by the end of one
week?
2.) To drink water, bats
skim the surface of a
stream and drink water
drop-by-drop or lick the
water off their fur. A big
brown bat flies a maximum
of 30 miles a night. How
close would the big brown
bat want its home to be to
water?
6.) A bat pup can weigh
30% of its mother’s body
weight. If a mother red bat
weighs 14 grams, how
much will her baby weigh?
If humans were the same
way, and a mother weighed
150 pounds, how much
would her baby weigh?
10.) In summer, bats that
will hibernate eat a lot to
store energy for winter.
They hunt after dusk and
before dawn. A little brown
bat catches 600 mosquitoes
in one hour. How many
mosquitoes can a little
brown bat catch in 4 hours?
3.) Bats eat insects like
moths. Bats can eat half
their weight in one night. If
a northern myotis weighs
12 grams and a moth
weighs 0.3 grams, how
many moths can the bat
eat before it feels full?
7.) A bat colony can have
over one million
(1,000,000) bats living in
one cave. Duluth has
86,000 people. How many
times would the population
of Duluth fit into a bat cave
colony?
11.) In fall, a hoary bat
migrates south to spend
the winter. A hoary bat
travels 1,400 miles from
Duluth to Texas. If a hoary
bat flies 20 miles per night,
how many nights would it
take the hoary bat to reach
Texas?
4.) A Minnesota bat can eat
half its weight in insects in
one night. How much food
could you eat in one night if
you were a bat?
8.) White-nose Syndrome,
a dangerous disease for
cave hibernating bats, can
kill 90% of a bat colony. If
a colony of 10,000 bats
becomes sick with WNS,
how many bats might die?
How many bats would
survive?
12.) In winter, some kinds
of bats hibernate. They
have to wake up to drink
water and urinate. If a
silver-haired bat wakes up
every 19 days during
hibernation, and winter in
Minnesota lasts six months,
how many times does a
silver-haired bat wake up?
www.nrri.umn.edu/bats