Geographic Range
Mauritian tomb bats (
Taphozous mauritianus
) are found widely distributed throughout the middle to southern regions of Africa,
as well as on several offshore islands. Individuals have also been recorded on the
islands of Madagascar and Bourbon, as well as a handful of islands in the Indian Ocean.
Habitat
Although generally found in moist, open habitats,
T. mauritianus
can also be found in savanna regions south of the Sahara that receive at least 500
mm of rainfall each year. Records of
T. mauritianus
in areas with less rainfall are usually close to swamps and rivers. These bats may
be dependent on open water for hunting.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- savanna or grassland
- forest
- rainforest
- Wetlands
- swamp
- Other Habitat Features
- riparian
Physical Description
Mauritian tomb bats are distinguishable from other bats by an entirely white ventral
surface, combined with mixed-gray dorsal pelage. They have sleek, short hair. Their
wings are long and narrow, generally with a pale, parchment-like coloration, and are
attached at the ankle. The long, narrow tip of the wing is shortened somewhat to facilitate
crawling when the wings are folded. The ears are erect, triangle-shaped, with rounded
edges and no papillae on the inner margins.
Mauritian tomb bats do not exhibit sexual dimorphism in coloration or size, although
there is evidence of geographic variation in size. In South Africa, the measurements
(in mm) of males and females, respectively, are: length of head and body, 101 to 109,
105 to 116; length of forearm, 61 to 63, 61 to 66; and length of tail, 17 to 25, 20
to 23. A typical male body mass (in g) in Southern Africa is 20 to 36, while an average
female mass is 27.5 to 31.6. The average wingspan is 181 to 204 mm.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Reproduction
There is little published research dealing specifically with the mating systems of
T. mauritianus
. It is likely that they are similar to other
Taphozous
species in this regard, with individuals engaging in polygynous relationships during
mating seasons.
- Mating System
- polygynous
There is conflicting evidence regarding reproductive cycles of
T. mauritianus
. Some research suggests the breeding season is in December, with births in April
to May. Other research suggests that they are either polyestrous or breed throughout
the year in some regions of Africa, with births occurring from March to April, as
well as November to December. Given the wide geographic range of this species, it
is likely that different reproductive strategies occur in different parts of the range.
Females give birth to a single young, which clings to its mother’s abdomen at all
times until it is old enough to fly and forage on its own.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
Parental investment in
T. mauritianus
is restricted to the female of any mating pair, and is similiar to the majority of
other bat species. The female gives birth to a single young, with remains with the
mother at all times until it is able to fly on its own. Although there is little to
no research in this particular area, it is possible that this time spent with the
mother allows the offspring time to observe hunting behavior and to learn other necessary
behaviors for later in life.
- Parental Investment
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
There is little research information available regarding the lifespan of
T. mauritianus
in the wild or in captivity.
Behavior
Day roosts are always chosen so that take-off is unhindered, and may be in the open
but out of direct sunlight. When disturbed, Mauritian tomb bats sometimes takes refuge
in a tree near their normal roost, or will simply scurry sideways across the roost
until they are out of sight of the intruder. Roosts are likely to be recolonized on
subsequent years, and these sites generally become stained with a mixture of urine
and gular sac secretions over time.
Mauritian tomb bats usually wait for complete darkness to fall before beginning to
forage. They detect their prey at long range over open areas, never flying above the
tops of nearby trees. When hunting, they make periodic dives of up to 10 meters. With
each dive they increase the rate of echolocation calling, possibly to confound moths
that would be able to detect the frequencies used by a foraging bat.
Home Range
It is thought that
T. mauritianus
individuals rarely travel far from their day roosting site, although little research
has been conducted on their movement patterns.
Communication and Perception
Mauritian tomb bats communicate primarily through audible calls, chirruping while
at rest but screeching when encountering aggressive situations. Whenever another
member of a roosting group approaches, the members of the group already in the roost
will emit three-syllable calls at 2-3 second intervals. The reason for these particular
social calls is currently unknown. Like most other mammals, they are likely to use
chemical cues and touch as well in social communication.
Mauritian tomb bats perceive their environment in different ways depending on the
amount of light available. During daylight hours, they rely primarily on vision to
identify intruders or prey that come too close to the roost. Once darkness has completely
fallen, they rely on orally emitted echolocation sounds to forage.
- Perception Channels
- visual
- tactile
- echolocation
- chemical
Food Habits
Although they have been observed to dart from their perches during daylight hours
to capture and eat prey items that wander too close,
T. mauritianus
is primarily a night-foraging species. Moths found close to their daytime roosts
are the staple of their diet, supplemented by termites, butterflies, and a variety
of other insects. They typically do not return to their roost to feed during nighttime
foraging, which is evidenced by the lack of prey debris or droppings beneath roosting
points.
Mauritian tomb bats use vision to pick out potential prey during daylight hours, rather
than echolocation. At night, they use orally emitted echolocation sounds to detect
prey at long range over open areas.
- Primary Diet
- carnivore
- Animal Foods
- insects
Predation
Snakes as well as nocturnal raptors occasionally prey on Mauritian tomb bats, although
specific predators are rarely named in the literature. Mauritian tomb bats occasionally
host parasites in the genus
Anchitrema
. These parasites may be transferred to them by African sheath-tailed bats,
Coleura afra
, which sometimes roost with Mauritian tomb bats.
Ecosystem Roles
Mauritian tomb bats are important in controlling pest populations in the ecosystems
they occupy. They consume large numbers of insects nightly. Mauritian tomb bats also
host parasites in the genus
Anchitrema
.
Economic Importance for Humans: Positive
Mauritian tomb bats help humans by controlling pest populations. The insects they
consume may carry diseases that harm humans or may simply be considered nuisance species.
- Positive Impacts
- controls pest population
Economic Importance for Humans: Negative
There are no known adverse affects of T. mauritianus on humans.
Conservation Status
Mauritian tomb bats are widespread throughout Africa and neighboring islands. They are not listed as requiring special conservation action under any current programs.
Additional Links
Contributors
Tanya Dewey (editor), Animal Diversity Web.
Chris Francis (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- swamp
-
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
- riparian
-
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- polygynous
-
having more than one female as a mate at one time
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- social
-
associates with others of its species; forms social groups.
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- echolocation
-
The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.
- chemical
-
uses smells or other chemicals to communicate
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
References
Bernard, R., G. Cumming. 1997. African Bats: Evolution of Reproductive Patterns and Delays. The Quarterly Review of Biology , Vol. 72: 253-274.
Dengis, C. 1996. Taphozous mauritianus. Mammalian Species , No. 522: 1-5.
Fenton, M., G. Bell, D. Thomas. 1980. Echolocation and feeding behaviour of Taphozous Mauritianus. Canadian Journal of Zoology , 58: 1774-1777.
Fenton, M., G. Bell. 1981. Recognition of Species of Insectivorous Bats by Their Echolocation Calls. Journal of Mammology , Vol. 62: 233-243.
Skinner, D., C. Chimimba. 2005. The Mammals of the Southern African Subregion . New York, NY: Cambridge University Press.