The Vampire Bat
Order
Family
Genus and Species
Chiroptera
Phyllostomidae Desmodus
rotundus
Vampire bats are small furry bats found in the
tropical
regions of Central and South America,
from Mexico to Chile, Argentina and Uruguay.
They also may be found on the Caribbean
islands of Trinidad and Margarita. They live mostly
on caves and hang upside down from the
walls and ceiling of the caves when sleeping. This helps protect them from predators.
Ancestors of these bats originated over
6
million years ago and are simply
mammals who,
over many centuries, developed leathery
wings and acquired the ability to fly. The vampire
bat got it's name from eerie stories originating
in Europe about bats which were reported to
drink human blood. According to the stories,
once a bat bit you.....then you would turn into
a vampire too. Bram Stoker wrote about
bats in the new world that attacked and sucked
the blood from unsuspecting humans. Just
the word vampire conjures up a feeling of dread.
There are three species of vampire bats: 1.
The White-winged vampire (
Diaemus
youngi ),
2.
The Hairy-legged vampire(
Diphyilla
ecaudata ), and the most abundant and studied
species, 3.
The common vampire bat
( Desmodus rotundus ), which we will cover in more
detail.
In the above graphic, this vampire bat is sucking the blood from the
wound he created by
biting into the toe of a chicken. Because
mammal blood is all that they feed on, the teeth
of the vampire bat are poorly developed, except for
the razor-sharp upper incisors and
and canines, which are used to puncture
the skin of their victims. After the initial cut is made
and blood has started to ooze from the wound.....the vampire bat secretes
it's saliva into the
wound. This saliva contains
an anti-coagulant which prevents the blood from clotting for
several hours. During this time, the vampire bat gets it's fill
of blood. Quite often, the same
bat will return to the same blood host for several days in a row.
Favorite targets of vampire bats are the larger animals such as
horses, cows, goats and pigs;
as well as domestic poultry. Calves
are especially targeted because their sleep tends to be
be deeper and of a longer duration. There have been reports
of humans being bitten by the
vampire bat.....mostly infants and mostly on
the outer extremities, especially the toes.
The common vampire bat weighs between 1/2 to
1 3/4 oz with a body length of 2 1/2 to 3
1/2
inches. Their mating season
lasts all year with a gestation period
of around 210 days. The
resulting birth is a single pup which weighs in at around 30
to 40% of the weight of the mother.
That would be the equivilent of a 120 lb. woman giving birth to a baby
weighing 36 to 48 lbs.
Vampire bats have a lifespan of 8 to 9 years
in the wild and around 18 years in captivity.
The
wingspan of an adult vampire bat is around 8
inches. These bats can consume over
40% of
their body weight in a single blood feeding and
sometimes have problems when trying to fly
back to their cave. Often bats must hide somewhere and wait for
an hour or two before they
are able to get off the ground. If they are threatened by predators
during this period of time,
they can rise up on their hind legs and
scurry away, using their wings as balance.
Young vampire pups are fed by the mother up until they are around 4
months old. This is when
they are introduced to hunting for appropriate mammals for their blood
meal. The mother shows
the youngster how to locate a host and how to create a wound large
enough to ooze blood. Then
when the pup is around 10 months old,
it is left to fend for itself. Numerous young pups never
grow to maturity because of natural predators, disease, or simply the
inability to locate a proper
host within two days. If bats can't feed for two
days in a row then they become weak and die.
The vampire bat in the above graphic is a lighter,
more yellowish color than most other vampires.
Every so often there are anomalies of nature
such as albinos and although some species will never
accept a different looking member of their species or ever welcome
them into the family structure,
vampire bats seem to have no such qualms.
Vampire bats are widely feared as disease vectors.
These bats will sometimes carry the rabies
virus and although it may not kill or
harm the bats in any way, this deadly virus may be spread to
many animals through contact with a single bat. In the early
thirties, a rabies epidemic broke out
in Trinidad, killing 89 people and
thousands of cattle. Finally it was evident
to everyone that
vampire bats were much more dangerous than previously thought.
Since vampire bats are nocturnal hunters
and will not venture out during a moonlit night, people
in Central and South America often have outdoor
after-dark activities when the moon is 3/4
full
to completely full. Although we
in the United States cannot really understand how people could
be too afraid to leave their homes on moonless nights, we do not have
a comparable situation nor
are most of us subject to the many fears and superstitions which
are widely prevalent in their part
of the world. The anthrax scare in
this country can give us some insight as to the mindset of these
people.
Press play below, to hear Vampire Bat sounds.