YUKON
Bats
© Government of Yukon 2007
ISBN 1-55362-266-9
Special thanks to Brian Slough and the Northern Research Institute, Yukon College,
for their contributions to this project.
Unless otherwise indicated, all photographs © Merlin D. Tuttle, Bat Conservation
International.
Illustrations by Jennifer Staniforth, except page 5 by Lea Randall
Maps by Environment Yukon
Printed on 100% recycled paper, including 30% post-consumer waste.
For more information on bats and other Yukon wildlife, contact:
Wildlife Viewing Program
Environment Yukon
Box 2703
Whitehorse, Yukon Y1A 2C6
Phone (867) 667-8291, Fax (867) 393-6263
Toll free in Yukon 1-800-661-0408, ext. 8291
[email protected]
www.environmentyukon.gov.yk.ca/viewing
1
A Guide to
YUKON BATS
What crosses your mind when you think of bats? Haunted
houses? Count Dracula? Gargoyles and devil’s wings? It is
no wonder bats get a bad rap. Bats seem mysterious and
scary to many of us, since we seldom see these creatures of
the night. A common reaction is to fear and harm what we
do not understand. In this booklet, we hope to dispel some
widely accepted myths and misconceptions about bats and to
increase understanding and appreciation of these remarkable
mammals.
Bats are common summer residents of southern and central
Yukon. Colonies of just a few individuals to several hundred
occupy natural and artificial roosts. They range as far north
as the Ogilvie and Wernecke mountains (between 64° and
65° north) north of Mayo, and the Yukon River, northwest of
Dawson City.
Telling bats apart is difficult unless you have one in hand,
something we don’t recommend. But, unless you live in
southeast Yukon, you can expect to see only
the hardy Little Brown Bat.
Bats often introduce themselves to
us by moving into our roofs, attics,
eaves or walls of cabins and houses,
where they scratch, squeak and
leave droppings. Health concerns
and ways to deal with unwanted
guests are addressed at the
back of this booklet.
You can help bats by learning
more about their secretive
lives, putting up a bat house,
and sharing this booklet!
Get to know bats and dispel
images like this one.
2
Beneficial bats
Little Brown Bat in flight
(approximately half actual size).
thumb
ear
elbow
fingers
foot
tail
Worldwide, there are over 1,000 species of bats, about one-quarter
of all types of mammals. Over 50 million years, they have developed
many sizes, body forms and food habits. We’re lucky to have them
around. Bats pollinate flowers (like the agave plant used for making
Tequila), disperse fruit seeds (many tropical trees depend only on bats
for dispersal) and keep insect populations in check. One colony of Big
Brown Bats can protect a farm from up to 18 million rootworms each
summer! All bat species found in Yukon eat nothing but insects.
Habitat is where it’s at. The Northern Long-eared Bat likes dense boreal forest with small
ponds. (Yukon Government, Cameron Eckert)
3
Bats at risk
Bats are particularly vulnerable to population declines. For mammals
their size, bats are slow to reproduce, often only giving birth to one pup
per year. So when bats are killed or their habitat is destroyed, recovery
is difficult and slow. Currently, many of North America’s bat species are
believed to be in decline or already listed as endangered.
In Austin, Texas,
Bat Conservation
International and citizens
rallied to save a colony
of Mexican free-tailed
bats by preventing
the destruction of a
bridge. Now, the Batfest
and viewing of threequarters of a million
bats contribute to the
economy by drawing
millions of tourists per
year. (©Karen Marks, Bat
Conservation International)
Will you go to bat for them?
Being Batman for the bats is easy. Just think about what bats need:
habitat (food, shelter, water and space). If you help to protect these
elements, bats will thank you with many benefits, some of which are
mentioned in this booklet. Here are a few tips:
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(standing dead trees) that have loose bark, especially balsam poplar or
aspen trees. Snags provide valuable roosts for bats and other wildlife.
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creating other housing for bats. See page 20 for ideas.
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sharing your new found knowledge with others. A good place to
start is “Want to Learn More?” on the inside back cover.
If you suspect illegal activity related to bats or other wildlife,
please call the Turn in Poachers (T.I.P.) Hotline at 1-800-661-0525.
4
Bat bits
Little Brown Bat
echolocating.
Myth: Bats are a kind of flying mouse.
Bats are neither birds nor flying mice.
They descended from a shrew-like
ancestor. They belong to the mammal
group known as Chiroptera, or the
“hand-wing.” There are two groups:
the Megabats (Megachiropterans),
or flying foxes of the Old World
tropics, and the smaller Microbats
(Microchiropterans) that occur
worldwide, including in Yukon. Our
bats are in the family Vespertilionidae,
the “evening bats.”
Biggest bat: The Gigantic Flying Fox
lives in Pakistan, India, Nepal and on a
few islands in the Indian Ocean. It has a wingspan of up to 1.8 metres!
Smallest bat: The Bumblebee bat is the size of your thumb tip.
Fastest bat: Big Brown Bats can fly at 40 km per hour. Our very own Little
Brown Bats are capable of flying 35 km per hour.
Bats are the only mammals that can truly fly. (Flying squirrels glide.)
Their wings are thin, double membranes of skin that stretch down long
fingers, arms, legs and tail. Bats also use their wings to warm their body
while roosting, to catch insects on the wing and to hold pups at birth.
Myth: Bats are blind.
Bats smell, hear, taste, feel and see, just like we do. But, because they
fly in darkness, they must rely on high-frequency sound to “echolocate” prey and to navigate. Sonar, or reflected sound waves,
provides the bats with information on distance,
speed, direction, texture and size of objects and prey.
Depending on the species, the sound waves are
emitted between 20 and 200 kHz, at an intensity
of 50 to 120 decibels. (An intensity of 120 decibels is
like listening to a jet take off a few metres from your head.) We
cannot hear bats echolocate because our audible range is .02
to 20 kHz. Normal human conversation ranges in frequency from 0.5 to
3 kHz, at an intensity of 50 decibels. A bat detector converts bat calls so
we can hear them. Bats also make audible squeaks when communicating
with each other and pups in the roost.
5
Myth: Bats fly into people’s hair.
You may feel a “swoosh” as bats deftly catch an insect that was attracted
to your head, but these expert flyers won’t get tangled in your hair.
Because bats emit high-frequency waves at short range (a few metres),
they may fly straight toward you and then veer off at the last second, as
soon as they detect your head. Enjoy the lucky experience!
Why do bats fly at night?
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birds stay up late, so bats get the nightflying insects all to themselves. Both
birds and bats eat spiders.
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there are fewer avian (bird) predators at
night.
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heat generated by muscles used for flight.
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BTB
nocturnal insectivore (night-flying insect eater). Because there
is no light to see with, bats developed echolocation, which is an
adaptation to being active at night.
Are bats allergic to cold?
Why don’t bats go further north than Dawson City in the Yukon?
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range beyond the Arctic Circle and have adapted to foraging in the
light of northern summer nights.
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featherweights may not have the energetic stores to migrate more
than 500 km.
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St. Elias ice fields!
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the staple of a bat’s diet.
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Also, bats are found in regions lacking large trees.
6
It’s a bat’s life
Bats have a long life for a small mammal with such a high metabolism.
They normally live for six to seven years, but one relative of our Little
Brown Bat in Russia survived 41 years! A shrew of similar size is an oldtimer at the age of two. Perhaps bats’ odd annual cycle has something
to do with it — they migrate AND hibernate!
Fall and winter
After migrating south, bats mate and begin hibernation. The female
stores the sperm for her single egg all winter.
Hibernation allows bats to conserve
energy at a time when temperatures
are cool and food is scarce. This is
why bats must not be roused from
hibernation, since they can quickly
burn off their modest fat stores.
Little Brown Bat hibernating, covered
in condensation.
During hibernation, bats reduce their
heart rate from 1,000 beats per minute
while flying and 100 to 200 at rest,
to 20 beats per minute. Their body
temperature drops from 40°C to 5°C.
They can stop breathing for up to
48 minutes at a time.
We don’t know where our Yukon bats
hibernate but we suspect they migrate to caves in coastal southeast
Alaska where the air is humid and temperatures remain stable and cool
at 1°C to 5°C. There may be suitable caves in interior Alaska, Yukon or
northern British Columbia, but none have been discovered. However,
bat caves have been found on Prince of Wales Island in southeast
Alaska.
Spring and summer
Bats emerge from hibernation in April and soon migrate to summer
habitats. We don’t know how much time is spent near the hibernating
sites or en route, but we do know that they return to Yukon in late April
and that some colonies build up in numbers through May and June.
7
Males and females typically
roost separately since they
have different temperature
requirements. However, bats are
loyal to their roosts and will return
year after year.
Females can breed at just two
months of age but males are not
sexually mature until their second
Bats in a cabin roost. (Brian Slough)
year. Female Little Brown Bats seek
out maternity roosts that keep a 30°C to 55°C temperature. This warmth
encourages rapid fetal growth and good milk production. They choose
roosts in rock crevices, behind the bark or tree cavities of snags, and
in cabins that are warmed by the sun. Roosts are often near water, for
drinking and foraging on insects, but they can be several kilometres
away. In early July, after 50 to 60 days gestation, each female gives birth
to a single pup. Afterwards, females and pups huddle in large numbers
(30 to several hundred) to keep warm.
Pups fly at two to three weeks old, and are weaned and self-sufficient
within a month. Nursery colonies start to break up in early August
when they move to other feeding areas and roosts or begin their
journey to hibernating sites. With increased movements and earlier
nights in late summer, many people observe bats at this time.
Males roost in cooler sites alone or in small groups. If temperatures
dip below 5°C, both sexes can go into torpor, a short-term state of
hibernation, to conserve fat. When bats leave their day roosts to forage
at night, they may use a variety of night roosts, where they rest and
digest food between foraging flights. These exposed roosts provide less
stable temperatures, so females do not use them while nursing.
Bats stay in Yukon long after the nursery colonies have dispersed.
We receive reports of bats well into September and even early
October.
Big Brown Bat
catching a moth.
8
Where to view bats
You don’t have to wait until Halloween to see real bats. In fact, you’ll
miss them if you do!
Bats arrive in Yukon in April and generally return south to warmer
climates by late September. The best months to view bats are June, July
and early August, when large nursery colonies are busy feeding in the
drawn out dawn and dusk of northern summers.
Bats eat night-flying insects. These insects tend to lay eggs in or
near water. Therefore, where there is water, there are probably bats.
Swarming insects attract more bats.
Abandoned lakeside cabins offer great bat hangouts. Bats live and feed
in almost any low-elevation habitat, but they seem to like the forestwater edge best. Look for flight corridors in the forest, including forest
openings and trails. Later in the summer, look for bats chasing insects
attracted to street lights.
Expect bats to fly out of their day
roosts a half hour after sunset.
Around summer solstice (June 21)
this can be up to one hour later.
For Whitehorse, this would be
midnight in late June and around
9:30 p.m. in late August. You will
have stay up even later to see
them in northern and western of
Yukon. It is most exciting when
the bats first leave the roost — all
within half an hour — but you
Little Brown Bat taking a break in a pine tree.
can watch individuals coming
(Jennifer Talerico)
and going until sunrise. They
won’t come out during the day, but they may spread their wings at
roost entrances to cool down in the heat.
The keen bat viewer can purchase a hand-held bat detector, but
following the above tips should guarantee viewing without one.
Bat bit: Twenty million Mexican free-tailed bats live in Bracken Cave,
Texas, eating 250 tons of insects each night. There are so many (largest
accumulation of mammals in the world) that their exodus compels the local
airforce base to shut down.
9
Key bat-viewing areas
Rock crevices
near water,
such as at
Miles Canyon, in
Whitehorse, and
Paint Mountain,
near Haines
Junction.
(Brian Slough)
Trails and forest
openings and
edges near water
and mature
forests.
(David Nagorsen)
Lakeside cabins
and shelters.
(David Nagorsen)
The Watson Lake
Airport Control
Tower.
(Tom Jung)
Mature forests
and large snags
near water.
(Tom Jung)
10
Little Brown Bat
Myotis lucifugus
Wingspan: 25 cm
Weight: 8 g (6-10 g)
Lifespan: Up to 34 years
Roosts: Human-made
structures, rock crevices, tree
cavities and under tree bark
This medium-sized bat has
cinnamon-buff to dark brown
fur above, and buffy to pale
grey fur underneath. Wing
membranes are dark brown.
Young of the year have dark
fur and their wings appear waxy.
Using bat detectors, researchers
can detect the Little Brown Bat by
its 2 to 5 millisecond echolocation call
sweeping from 78 to 38 kHz.
Little Brown Bats often feed over water and along the margins of
lakes and streams, but they will also hunt in clearings and in forests
throughout southern Yukon. They are most active the first two to
three hours after leaving the roost at dusk. They continue to forage
throughout the night between periods of roosting to digest food.
Males and females lead separate lives. Males live alone or in small
colonies, often in cooler day roosts and in marginal habitats at higher
elevations (but less than 1,000 m) than the females. Females prefer
roosting in larger (warmer) colonies of up to several hundred bats (the
largest found in Yukon had more than 400).
We know very little about
male Little Brown Bats in
Yukon. They make up less than
10% of colonies.
Old, dead and dying trees offer great roosts
for bats on or under bark and in cavities
made by birds. (Tom Jung)
0
1
2
3
4
5
6
7
8
9
10
Distribution of the Little Brown Bat
Old
Crow
Bat bit: When most
active, one Little
Brown Bat can
catch up to 1,200
mosquito-sized
insects in one hour!
w
rth
Alaska
(USA)
No
Yukon
e rr
t T
es
Dawson
ito
rie
s
0
11
Whitehorse
Watson Lake
0
100
British Columbia
200
Kilometres
Little Brown Bats arrive between April and June and leave between
August and October. We believe they hibernate in southeast Alaska, but
we don’t really know. Bats from eastern Yukon may hibernate in British
Columbia. There are no known
hibernating sites for bats north
of Prince George.
The Little Brown Bat
conservation status in Yukon
and Canada is Secure due to
its widespread distribution
and apparently healthy local
populations. However, in
Yukon it occurs at relatively
low densities. Population
trends and wintering areas are
unknown.
1
12
13
14
One of the best known Little Brown Bat
colonies can be viewed at Chadburn Lake
Recreation Site, near Whitehorse. (Brian Slough)
15
16
17
18
19
20
12
Northern Long-eared Bat
Myotis septentrionalis
Wingspan: 23 cm
Weight: 6-9 g
Lifespan: About 20 years
Roosts: Human-made structures, tree
cavities and under tree bark
Northern Long-eared Bats were first
captured in the La Biche River valley
of southeast Yukon in 2004. The
species has also been documented
in Watson Lake, northeastern British
Columbia and Northwest Territories.
We expect that it ranges more widely
in the southern Liard River Basin, east of
Watson Lake.
Outwardly similar in appearance to the Little
Brown Bat, the Northern Long-eared Bat has dark
brown fur on the back and pale or tawny fur on the
underside. Though its body is smaller, its ear is actually 4 mm longer
than the Little Brown Bat’s!
The Northern Long-eared Bat forages within dense boreal forest. It has a
1 to 3 millisecond call sweeping from 110 to 38 kHz.
The Northern Long-eared Bat, designated May Be At Risk in Yukon, has a
narrow range and small populations, and may be affected by land use
activities such as forestry. It is Secure in Canada. More information is
required to determine whether or not the species is at risk.
No
w
rth
Dawson
Yukon
ito
err
tT
es
s
rie
Alaska (U
SA)
Confirmed sightings of Northern Long-eared Bat
Whitehorse
Watson Lake
0
100 200
Kilometres
British Columbia
13
Big Brown Bat
Eptesicus fuscus
Wingspan: 33 cm
Weight: 15-18 g
Lifespan: About 20 years
Roosts: Human-made structures
The Big Brown Bat is known only
from recordings made in the
Teslin area in 1999 and 2007. It
may be an occasional visitor or a
common resident. Documented
in northern British Columbia and
Alberta, the Big Brown Bat may
also live in southeast Alaska and the
Northwest Territories. A single record of the
Big Brown Bat exists for central Alaska.
Like the Little Brown Bat, this bat often lives in buildings.
It has similar habits for roosting, feeding, migration, reproduction and
hibernation but it is physically larger. It is also less tolerant of high
temperatures, preferring roosts below 35°C. It has a large broad head
and long pale to dark brown fur that appears oily. This bat is also one of
the earliest to emerge at dusk.
The Big Brown Bat call sweeps from 33 to 26 kHz in the first
3 milliseconds, ending in a 2 to 7 millisecond constant, sounding like a
“put” on the bat detector.
The conservation status of the Big Brown Bat in Yukon is Undetermined
until it is confirmed in Yukon and more information becomes available.
It is Secure in Canada.
Sightings of the Big Brown Bat
Dawson
w
rth
Yukon
ito
e rr
tT
es
s
rie
Alaska (U
SA)
No
Bat bit: One colony
of Big Brown Bats
can protect a farm
from up to 18 million
rootworms each
summer.
Whitehorse
Watson Lake
0
100
200
Kilometres
British Columbia
14
Is it a Myotis migration or more monitoring?
Only three species of bats have been documented in Yukon. But how
many species do we really have? Several other species are known to
live just across Yukon’s borders.
The Western Long-eared Bat (Myotis evotis) lives in northern
British Columbia and the California Bat (Myotis californicus) in southeast
Alaska. The Long-legged Bat (Myotis volans), Keen’s Bat (Myotis keenii)
and Silver-haired Bat (Lasionycteris noctivagans) have been found in
both northern British Columbia and Alaska.
A 2006 study in the Nahanni River drainage, very
close to Yukon’s southeast border, found seven
species: the Western Long-eared Bat (Myotis
evotis), the Long-legged Bat (Myotis volans),
the Hoary Bat (Lasiurus cinerus), the
Eastern Red Bat (Lasiurus borealis), the
Little Brown Bat, the Northern Longeared and the Big Brown Bat. This is
the most northerly (61°N) record of the
Western Long-eared and Long-legged
bats in North America, extending their
range about 300 km!
As a result of more bat studies, as well as
changes in climate, how many more species
will we discover in Yukon?
Bat species found near Yukon borders
The Hoary Bat is the
greatest migrator
of Canadian bats. It
weighs 30 grams,
the weight of four
loonies.
Northwest Territories
Yukon
Whitehorse
Watson Lake
a(
sk
Ala
A)
US
British Columbia
0
100
200
Kilometres
Eastern Red Bat
Hoary Bat
Keen’s Long-eared Bat
KEY
Silver-haired Bat
Long-legged Bat
Western Long-eared Bat
15
Contribute to science!
Yukoners have observed bats for hundreds of years
and western scientists have studied them since
the early 1900s. However, the first bat map was not
produced until 1975 and only the Little Brown Bat
was included. Two new species were found after
research and monitoring increased in 1995.
Bat detectors record
ultrasonic bat calls
nightly, for up to a
week. (Tom Jung)
Still, most information is new information.
Researchers are
particularly keen
to hear about
If you see interesting bats or large
natural roost sites,
colonies, please report them to
hibernation areas
the Wildlife Viewing Program.
and migration arrival
and departure dates
from your area.
How do they survive our short and cold summer
nights?
Do they behave differently in
the north than in the south?
Will you discover the missing
piece?
Bat observation sites
(live capture, echolocation recording and other observations)
0
s
rie
Alaska (U
SA)
Yukon
ito
e rr
tT
es
(Tung Jung)
100
Kilometres
w
rth
Bat researchers
capture, band and take
tissue samples to find
out genetic variation,
roost fidelity,
longevity, movements
and, by chance,
hibernation sites.
No
Dawson
Whitehorse
Watson Lake
British Columbia
200
16
Should I be worried about bats?
Myth: Bats are a major threat of rabies to humans
Rabies
One of the greatest misconceptions about
bats is that most bats are rabid. News about
bats and rabies is often exaggerated. Less
than one-half of 1% of bats contract rabies.
This is no more than other wild animals. Our
northern bats, which live in small isolated
populations, likely have a negligible rate of
infection. A survey of areas in northwestern
North America found a rabid bat in southeast
Alaska, and no cases of bat to human transfer.
There is only one documented case of batcaused rabies in humans in British Columbia.
Little Red Flying Fox
Because sick bats die quickly, they cannot cause rabies outbreaks in
other bats or animals. They usually only bite in self-defence and do
not become aggressive like rabid dogs. Also, there is no rabies in bat
droppings. Nonetheless, the best precaution is to avoid handling
bats, or any other wild animals, and to be sure your dogs and cats are
vaccinated.
Parasites
Like all mammals, bats are infected with parasites like fleas, mites
and bat bugs (similar to bed bugs). Parasites are host-specific and will
rarely bite humans or pets. They are occasionally seen in piles of bat
droppings but quickly die when removed from the host.
If you encounter a bat that appears sick or shows no fear of humans, do not
touch it. Report it to a Conservation Officer at 1-800-661-0525 (toll free).
If you are bitten by any animal, including bats, seek medical help immediately.
For more information on bats and health issues, contact Yukon Communicable
Disease Control at (867) 667-8323 or 1-800-661-0408, ext. 8323 (toll free in Yukon).
17
Myth: All bats drink blood
There are a few South American species that live off the blood of
animals, but 99.7% of bat species do not. Some bats eat only pollen;
others only fruit. One bat is able to eat toxic frogs. However, all bats in
the boreal forest hunt insects that fly at dusk or at night.
Insects, look out!
Bats are the ultimate bug zappers! They have a high metabolism, and
a nursing female can eat up to one half of her body weight in insects
— almost four grams — every night. A single Little Brown Bat can
consume 1,200 insects in an hour, and a nursing mother may eat 4,500
in a night!
Many of these are mosquitoes and agricultural and forests pests that
do not have predators at night. A colony of 100 Little Brown Bats
can eat almost 20 kilograms of insects in four months. A Little Brown
Bat foraging over water will catch and consume midges, mayflies,
caddisflies and mosquitoes, while those foraging in forests will catch
moths, spiders (not an insect), flies, beetles and other insects by picking
them off vegetation or the ground.
A Pallid Bat with a scorpion in tow.
18
Help! I have bats in my house!
Bats that move into your home, or bats that forage nearby, occasionally
enter your living area through openings in windows, doors or chimneys.
If a bat flys into your house, don’t panic. Turn off the lights and open
all the doors and windows. The bats will quickly find their way out.
If they are roosting (hanging upside down) you can catch them with
a pillowcase or cardboard box. With gloved hands, reach into the
pillowcase, grasp the bat, then invert the pillowcase with the bat inside
and transport it outdoors for release. Otherwise, bats can be scooped
from the floor with a shovel and placed in a ventilated box. To avoid
being bitten, always wear leather gloves when handling bats.
One of the most common encounters with
humans is when bats roost in your house or
cabin, usually in the roof, attic, eaves or
walls. You may be able to tolerate a few
bats, but when a nursery colony moves
in, you may not enjoy the scratching and
squeaking pups, and the sight and smell
of bat droppings (guano). Bat droppings
are mostly insect parts and crumble
to the touch, unlike similar-looking, but
solid, mouse droppings. You may see the
droppings below roost entrances or splattered
on outside walls.
Bats in a
ceiling.
Bats return to the same roosts year after year, so problems (Brian Slough)
should be dealt with as soon as possible to avoid
expensive cleaning jobs and replacement of stained ceilings.
Bats can squeeze through
holes the size of a quarter.
To keep them out of your
house, carefully seal all
windows, soffits and eaves
with foam or caulking, and
fix places where joined
materials have warped or
shrunk. (Brian Slough)
19
Tips for evicting unwanted guests
Note: Any large colony will be nursing or pregnant females. These should
not be evicted until the young are self-sufficient.
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after they leave in September.
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make your work easier.
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cracks or holes, sometimes stained
by oily fur, and areas above piles
of droppings. These access points
must be sealed with screening or
polyurethane expanding foam.
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foil or Mylar balloons in attics or
near roost entrances to discourage
bats by interfering with their sonar. There are
no known effective ultrasonic or chemical
deterrents for displacing or discouraging
active colonies.
t 5PBMMPXCBUTUPFYJUCVUOPU
get back in, build a one-way
sleeve exit with screening and
place over the entry point you
have identified.
Exclusion technique: one-way door.
Eviction is stressful for bats, and it only
moves the problem to your neighbour’s
cabin. Bats may die. It may be difficult to
expel all of the bats if entrances can’t be
found or sealed. Providing a bat house as an alternative roost may solve
these problems.
20
Bat condominiums
With more well-sealed buildings, where will the bats roost? Bat houses,
or bat boxes, can fill that void. Bat houses are designed to meet the
day roosting requirement of bats and can be modified to meet the
preferences of local bat species and climates. You can buy bat houses
commercially or build your own.
We have been experimenting with
bat houses in Yukon and recommend
some modifications for our dominant
species, the Little Brown Bat, and
our cool climate. Bat houses should
be fully caulked, unvented, painted
or stained a dark colour to absorb
sunlight, and mounted high on
the south-facing wall of a building.
Roosting crevices should be no more
than 2 cm in width.
This homeowner enjoys constant
natural pest control thanks to bats
by night and swallows by day.
(Brian Slough)
Use your imagination! Some advanced
designs include sand-insulated walls
to moderate temperatures, and a
heating pad or a plant pot heater
wired to a thermostat.
Be patient. It may take a year or two
for bats to discover and occupy a new
house, but the wait will be worth it.
Happy bat viewing!
Build your own bat house by requesting detailed instructions from
Environment Yukon’s Wildlife Viewing Program. (Yukon Government)
21
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of their hind limbs. This may be why they can’t walk, run or
stand.
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and in groups, preserving body heat.
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body. No muscles or energy are involved. Bats can hibernate
or go into torpor without fear of falling.
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thumbs.
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(place in nature) for roosting.
There are many theories as to why bats evolved the unique
ability to hang upside down. What do you think?
Why do bats hang upside down?
Want to learn more?
Books
Fenton, M.B., 2001. Bats. Fitzhenry & Whiteside, Markham, Ontario.
Nagorsen, D.W. and R.M. Brigham, 1993. The Bats of British Columbia. Royal BC
Museum Handbook, Volume 1: The mammals of British Columbia. UBC Press, in
collaboration with the Royal BC Museum, Vancouver, British Columbia.
Oppel, K., 2006. The Silverwing Saga. Harper Collins Canada. (children’s book)
Tuttle, M.D., M. Kiser and S. Kiser, 2005. The Bat House Builder’s Handbook. Bat
Conservation International, Austin, Texas.
van Zyll de Jong, C.G., 1985. Bats. Handbook of Canadian Mammals, Volume 2.
National Museum of Natural Sciences, National Museum of Canada. Ottawa, Ontario.
Websites
Alaska Bat Monitoring Project, www.akbats.net
Bat Conservation and Management, www.batmanagement.com
Bat Conservation International, www.batcon.org
Buzbee’s Bat House, www.batbox.org
Environment Yukon: Yukon Mammal Series, www.environmentyukon.gov.yk.ca
Public Health Agency of Canada, www.phac-aspc.gc.ca/im/vpd-mev/rabies_e.html
Yukon Communicable Disease Control, www.hss.gov.yk.ca/programs/health/ycdc
For free distribution only.
www.environmentyukon.gov.yk.ca/viewing
Environment