Taphozous mauritianus E.Geoffroy, 1818

Ventral Coloration

The Mauritian tomb bat, scientifically named Taphozous mauritianus E.Geoffroy, 1818, can be distinguished from other bat species by its completely white ventral area.

Dorsal Coloration

The dorsal surface of this bat is mottled with multiple shades of brown, gray, and white, creating a grizzled "salt and pepper" appearance.

Fur and Wing Structure

It has short, sleek fur, and its primarily translucent beige wing membranes are attached to long, narrow wings. When not in flight, the wings shorten to make crawling easier — a trait unique to this genus.

Color Dimorphism and Age Variation

Males and females are similar in both color and size. Generally, adults are lighter in color than juveniles, which have a more prominent gray hue.

Facial Features

This species has a cone-shaped face covered with a thin layer of hair, the area below and in front of the eyes is hairless, and the front of the face is sunken around the large (2–3 mm) eyes.

Ear Structure

Its ears are triangular, erect, and have rounded edges, and the inner margins of the ears do not have papillae, the inner sensory surface of a bat's ear.

Size and Weight

As one of the larger species in the Microchiroptera suborder, fully grown adult Mauritian tomb bats weigh 25 to 36 grams (0.88 to 1.27 oz), with forearms measuring 58 to 64 millimetres (2.3 to 2.5 in) and total body lengths of 10 to 11 centimetres (3.9 to 4.3 in).

Distribution Range

The Mauritian tomb bat has a wide distribution across central to southern Africa, and on many of the surrounding islands.

Recorded Countries of Occurrence

It has been recorded in Angola, Benin, Botswana, Central African Republic, Chad, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Equatorial Guinea, Ethiopia, Gabon, Gambia, Ghana, Kenya, Madagascar, Malawi, Mauritius, Mozambique, Namibia, Nigeria, Réunion, São Tomé and Príncipe, Senegal, Seychelles, Sierra Leone, Somalia, South Africa, Sudan, Swaziland, Tanzania, Togo, Uganda, Zambia, and Zimbabwe.

Kidney Adaptation for Water Conservation

Special kidney adaptations help the Mauritian tomb bat conserve water, allowing it to survive in the frequently dry, semi-arid regions of countries like Sudan and Chad.

Renal Structure

This bat has a mean renal index of 5.55: its inner kidney medulla (the section that collects waste) is very large relative to the overall organ size, letting it remove most waste from the water it consumes.

Urine Concentration Ability

The species has a predicted mean maximum urine concentration of 3,921 mosmol/kg, meaning it produces very concentrated urine.

Ecological Conclusion on Renal Traits

From these traits, scientists have tentatively concluded that the species' kidneys support effective water conservation.

Habitat Types

Mauritian tomb bats occur occasionally in grassland biomes, as well as semi-arid and tropical regions, including forests, rainforests, grasslands, and parts of the Sahara that receive less than 500 mm of rainfall per year.

Preferred Habitat Features

They prefer open, moist savanna with plenty of room to maneuver and roosting sites close by, and are often found near open swamps and rivers that provide a steady food supply; open water may also be necessary for hunting.

Avoided Habitat

This species avoids dense sections of tropical forest because it has limited turning maneuverability.

Agricultural Roosting Habitat

In countries such as São Tomé and Príncipe, groups of Mauritian tomb bats roost in cocoa trees on large plantations, which provide a good environment with suitable roosts, adequately spaced trees, and abundant insect prey.

Roost Site Selection Criteria

Mauritian tomb bats prefer roosting sites that have overhead shelter but are in exposed positions to make takeoff easier.

Natural Roosting Locations

Natural roosting locations include palm tree trunks, caves, and crevices.

Anthropogenic Roosting Locations

Since human settlement, they have adapted to roost in new locations including building sides and, as their common name suggests, tombs.

Roost Surface Preference

They prefer buildings with bare brick surfaces over painted ones, as bare brick provides better grip.

Roost Takeoff Clearance

They select day roosts such that no obstacles block takeoff.

Typical Group Size

Mauritian tomb bats are most often found in groups of around five individuals.

Group Gender Segregation

These groups are usually entirely male or entirely female; in mixed-gender groups, males and females are separated by at least 10 centimetres (3.9 in).

Gender-Specific Group Structure

Females live together in groups of 3 to 30, while males live alone except during the mating season.

Roosting Spacing Behavior

Unlike some bat species, they do not roost tightly packed together, and instead space out loosely — the only exception is a mother and her offspring.

Large Group Observations

In some locations, including Shai Hills Resource Reserve in Ghana, groups of at least 100 bats have been observed.

Roosting Posture

They typically roost with their ventral side pressed flat against a surface.

Diurnal Roosting Behavior

The Mauritian tomb bat is nocturnal and rests during the day, but does not sleep much and remains alert while roosting.

Disturbance Response

If disturbed, it will fly to a new site or move quickly under building eaves.

Roost Site Fidelity

It very rarely travels far from its day roosting site, and roosts are often recolonized over time.

Roost Staining Characteristics

Over time, roosts become stained brown with gular sack secretions and urine; these stains are typically rectangular, around 150 mm long and 100 mm wide.

Eyesight Evolution Context

The species' semi-diurnal activity has led to the evolution of relatively good eyesight, unlike most echolocating bats.

Vision Convergent Evolution

Its vision is very similar to the vision of Old-World bats, and the presence of the dim-light (RH1) gene in both Mauritian tomb bats and Old-World bats suggests convergent evolution of this gene in similar light-rich environments.

Visual Acuity

Mauritian tomb bats can detect movement from far away, indicating their eyesight is superior to that of other insect-eating bats.

Eyesight Functions

This advanced eyesight plays a large role in selecting suitable day roosts and detecting predators.

Hunting Period

The Mauritian tomb bat is mostly a nocturnal hunter, though it occasionally forages during the day.

Hunting Habitat Preference

It prefers to hunt in open spaces like open fields or bodies of water, so it can easily swoop down to catch insect prey.

Prey Capture Method

It captures and consumes prey while still in flight.

Prey Preference

Its preferred food is moths, though during daylight it preys on butterflies and termites.

Pest Control Role

In the regions it inhabits, it often helps control pest populations, which is important because these areas are frequently affected by insect-borne diseases such as malaria.

Foraging Onset Time

It usually waits until full darkness before starting to forage.

Hunting Echolocation Behavior

It can detect prey at long ranges over open areas, makes periodic dives while hunting, and increases its echolocation rate with each dive.

Mating System

Mauritian tomb bats are polygamous.

Mating Frequency

Depending on the region, they mate once or twice per year.

Southern African Reproductive Schedule

Populations in the Southern African subregion often produce two pups annually: one born in February or March, and another born between October and December.

Other Population Reproductive Schedule

In other populations, mating occurs in December, followed by a four to five month gestation period, and birth takes place in April or May.

Litter Size

Mothers give birth to one pup per litter.

Parental Care

Only mothers care for young after birth, and males do not participate in raising offspring.

Maternal Pup Carrying Behavior

The pup clings to its mother's abdomen when she flies and when she is perched.

Pup Dependency Period

It stays with the mother, clinging to her chest wherever she goes, until it is able to fly.

Nursing and Weaning

The mother nurses the pup during this time, and the pup drinks her milk until it is weaned onto the adult insect diet.

Juvenile Skill Development

The time spent with the mother lets young bats observe hunting behavior and learn other skills they need to survive as adults.

Post-Fledging Dispersal

Once a young bat can fly, it can forage on its own, and may either stay in its mother's colony or join a different colony once fully grown.