Average Size
Adults
in the wild have a body length of 6-8 inches (15-20 cm) and a wingspan of
2 1⁄2 - 3 1⁄2 feet (76-107 cm). They weigh only 12-16 ounces
(340-454 g).
Habitat
Rodrigues
fruit bats depend on dense tropical rain forests for their food supply,
roosting areas and shelter. |
Physical
Characteristics
All bats possess clawed thumbs; megabats also have a claw on their
second finger. The wings of a bat are its “hands,” comprised
of four elongated digits between two layers of skin. Fruit bats use
their wings for warmth or cooling. They have long-toed feet with
sharp claws. Bats lack weight-bearing hind limbs, so they roost hanging
upside down and launch by releasing their grip. Unlike smaller insect-eating
bats, megabats do not use echolocation to locate food. Instead, fruit
bats have large eyes and a good sense of smell. Rodrigues fruit bats
have thick, dark brown fur with gold to red fur on their heads, necks
and shoulders. |
Life
Span
Unknown
in the wild, up to 35 years in zoos |
Diet
In the wild: Leaves, flowers, nectar, pollen
of mango, fig and tamarind trees.
At the zoo: Fruit
and vegetables plus marmoset diet. |
Reproduction
Rodrigues
fruit bats reach sexual maturity around 2 years old. In the wild, they
breed seasonally to time births when food is most plentiful at the start
of rainy season. Adult males claim and mark a small territory with a
strong musky scent produced from neck and shoulder glands. After rubbing
against branches and even females, they acquire a harem of up to eight
individuals. To mate, males approach the female, usually from the rear,
and grasp her by the neck. Copulation occurs while upside down.
Gestation
takes about 150 days, and the mother produces a single pup. A female
allows gravity to assist in giving birth. She hangs by her thumbs
and uses her hind legs to guide the emerging infant onto her abdomen.
If the bat pup does not cling immediately, the female may use her wings
to catch it for proper positioning. She then flips upside down again
with the pup tucked inside her wing.
Life Cycle
The tiny bat emerges with open eyes and covered with fur. It quickly moves to
a nipple to nurse and remains safely under its mother’s wing. Besides
its hand and foot claws, the young bat has extremely sharp and hooked milk
teeth that allow it to hang on and nurse, even during flight. By 3 weeks
of age, when the young becomes too heavy, the female leaves it behind while
she is away feeding. At 8 weeks of age, the young begins to move independently
and flaps its wings to strengthen them. At this time, the mother weans the
young and shares chewed-up food. By 7 months, the bat is fully independent.
Been
Camping in a Bat Colony?
Fruit bats live together in a colony in a “camp tree.” A colony
contains a large, mixed and long-term breeding group. Dominant adult males
claim the top or center locations, while subordinate males and juveniles of
both sexes position themselves on the outskirts. Adult females move around.
During the daytime roost period, members interact with each other and move
about. They may seek the top of the tree for sunbaths. “Aunting” behavior
is common among Rodrigues bats. Females may take young from the mother and
enfold them underneath their own wings.
Finding
Fruit for Food
These nocturnal bats leave the roost at dusk to eat. Their good senses of smell
and sight locate food sources. Fruit bats use their clawed digits to grasp fruit
and they bite off pieces with their sharp teeth. They chew the fruit and crush
it against their hard, ridged palates. Juice is swallowed and the pulp is spit
out as a small pellet. Rodrigues bats “chatter” constantly during
feeding periods. At dawn, they return to the camp tree.
|
Fascinating
Facts
- In
order to eliminate waste, a bat grasps overhead with its
claws and raises its head to avoid urine or feces!
- The
word Chiroptera comes from the Greek language, and means “hand
wing”!
- Rodrigues
bats require high humidity to preserve their fur and to avoid
drying out their wing membranes!
|
Night
Exhibit
Rodrigues fruit bats are in the Night Exhibit, across from the African
straw-colored fruit bats. The Night Exhibit also has vampire bats.
After the zoo closes, the light in this exhibit is gradually brought
up to an artificial “day” lasting between 10-14 hours.
During this “day,” the nocturnal Rodrigues fruit bats sleep.
They become active during the zoo visitor’s day as their “night” begins.
The lights gradually dim to simulate dusk, then darkness.
The Rodrigues
fruit bat is critically endangered*. Island species of bats are especially
vulnerable. In the early 1970s, there were fewer than 100 left in
the wild. Rodrigues is susceptible to tropical storms. A devastating
cyclone hit Rodrigues in March of 2003, destroying much vegetation.
Deforestation and human predation for food further exacerbate the
endangered status of these bats. Conservation programs address these
problems. In the 1970s, 23 wild-caught Rodrigues bats created the
basis for the first two captive-bred colonies; these were sent to
aviaries in Mauritius and in the United Kingdom. These bats in zoos
are part of an international Species Survival Plan (SSP). Captive
breeding is very successful, so techniques such as birth control
or maintaining single-sex groups manage the population. Today, there
are more than 750 individuals in over 30 institutions. Woodland Park
Zoo (WPZ) aids this process by housing an all-male colony that originally
came from Brookfield Zoo. A WPZ staff member serves on the AZA Bat
Taxon Advisory Group and helped develop education materials used
on Rodrigues. As a way to spread awareness of this rare and endangered
species, WPZ and other zoos provide financial support to the Rodrigues
Environmental Educator program. At this time, there is no plan for
reintroduction into the wild.
How You Can Help!
The effort to save endangered species requires cooperation and support
at the international, national, regional and individual levels.
You can help in this cause. Join and become active in Woodland
Park Zoo or other conservation organizations of your choice. Do
not buy products made from wild-caught animal parts. Contact your
elected representatives and express your views about conservation
of endangered species and wild habitats.
Contact
Woodland Park Zoo at webkeeper@zoo.org to find out how you can
support conservation programs at the zoo or visit our How You Can Help page.
Sources
and Suggested Reading:
Internet
Sources
Association
of Zoos & Aquariums Bat Taxon Advisory Group. 1998. Rodrigues
Fruit Bat 98 Fact Sheet and IV. Reproduction. From: www.aza.org.
Bat Conservation
International: www.batcon.org.
Organization
for Bat Conservation: www.batconservation.org. Jamieson, Heidi. 2000.
Meet Some Bats.
Books
and Articles
Richarz, Klaus and Limbrunner, Alfred. 1993. The World of Bats.
TFH Publications, Neptune City, NJ. 192 p.
Nowak,
Ronald M. 1994. Walker’s Bats of the World. Johns
Hopkins University Press, Baltimore, MD. 288 p.
Whitman,
Kim. 1999. A Personal Portrait of the Rodrigues Fruit Bat.
Bat Conservation International.
*Taxonomic
classification varies between references. Classification information
used in this fact sheet taken from Mammal Species of the World: A Taxonomic
and Geographic Reference, edited by Don E. Wilson and Dee Ann M. Reeder,
Second Edition, 1993.
**Woodland
Park Zoo identifies an animal or plant endangered if it is listed as
endangered
(in any part of its
range) on the federal list of Endangered and Threatened Species,
or if is listed on Appendix 1 of the Convention on International
Trade in Endangered Species of Wild Fauna and Flora (CITES). |
Classification
and Range
