Taphozous melanopogon phillipinensis

Geographic Range

Philippine tomb bats ( Taphozous philippinensis ) are a subspecies of the widespread species, black-bearded tomb bats , found throughout much of south and southeast Asia and the Malay archipelago. Philippine tomb bats are found exclusively on the islands of the Philippines.

• Biogeographic Regions
• oriental oriental
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

Philippine tomb bats inhabit a variety of areas, from rainforests to woodlands. They are often found in hilly forest country near water but they may roost in many places including tombs, caverns, caves, rock crevices, sea cliffs, and trees. They are also becoming common in urban areas, roosting in buildings and churches. The bats are very agile while crawling, and are able to cling to sheer rock surfaces. This enables them to live places where other bats may not. Also, they often roost in well-lit areas that other bats avoid. Philippine tomb bats are gregarious and their relatively large colonies have been recorded with up to 4,000 individuals. Typically, adult males stay within their defined "territory" on the wall, and groups of females roost around them.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• rainforest rainforest

• Other Habitat Features
• urban urban
• suburban suburban

Physical Description

Philippine tomb bats have a head and body length between 62 and 100 mm, a tail length between 20 and 35 mm, and they weigh between 10 and 50 g. Their fur is white and tipped with pale brown to reddish-white. The fur on their underside is even lighter brown/tan to white. Their ears and membranes are thin and light colored, appearing white; the legs and feet of are covered with short fur. They have a simple muzzle, with no complex noseleaf. Their ears are short to moderate in length and have a short, rounded tragus. There is a well developed wing pouch that helps distinguish them from other Taphozous species. Juveniles are typically darker than adults. Adult males have a black "beard" of fur at the bottom of their jaw/top of their throat. This can make T. philippinensis easily identifiable, but the beard does not always appear. New research indicates this beard reflects seasonal changes and may have a role in mating systems.

Philippine tomb bats are unlike other Taphozous species in that they do not have the glandular sac that characterizes others in the genus. Instead, they have small pores in place of the sacs that open into the throat.

The wings are long and narrow, contributing to fast, long flights to forage. Philippine tomb bats fly high and fast, picking insects out of the air. Their wings are not adapted to agile flight or hovering and so they do not glean prey off the ground or off of plants. Instead, T. philippinensis catches flying insects by "netting" them with their flight membranes and eating them mid-air.

The tail of Philippine tomb bats penetrates the interfemoral membrane near the center and are exposed on the dorsal side; this gives them their nickname sac-winged bats . The dental formula is like other members of Emballonuridae : 2/3, 1/1, 2/2, 3/3. The first upper premolar is minute, and there is a large gap between the upper incisors.

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes colored or patterned differently
• male more colorful
• ornamentation ornamentation

Reproduction

Male Philippine tomb bats are polygynous and will mate with multiple females. There is one mating season per year, from January to February. Female Philippine tomb bats mate with only one male and produce a single young during each mating season. During the mating season, it has been observed that small glands in adult males excrete a thick sticky substance that collects on their beards. Information on the exact nature and function of this excretion is not yet available. It is likely that this substance contains hormones/pheromones designed to help attract mates.

The mating system is characterized by resource defense polygyny. This mating system involves the male providing and defending resources essential to females. The primary resource male Philippine tomb bats defend are safe nesting sites. Since Philippine tomb bats often roost in large colonies of thousands of individuals, a safe nesting site is essential to the upbringing of young. The quality of the nesting site and the ability of a male bat to defend it determines his mating rank with females. Those males that are most successful at this resource defense are able to mate with the most and best females.

• Mating System
• polygynous polygynous

The mating season of Philippine tomb bats lasts from January to February. During this time, males mate with as many females as possible. Each female mates only until she is pregnant. The gestation period lasts 3 to 4 months, and a single young is born between April and May. This single offspring is nursed by the mother for 8 weeks. After this time, the young are able to feed for themselves and leave the mother forever. There is no paternal care provided by the males. Information on the age at which Philippine tomb bats reach sexual maturity is unavailable.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

The parental investment found in Philippine tomb bats is provided exclusively by the mother. The mating system is polygynous, so a male may father multiple offspring. However, he will not provide and care for any of his young. The mother will provide nourishment/food, shelter, and protection for the young. Weaning will conclude about eight weeks after birth, and at this time the young will learn to catch insects and other prey on their own. Once the young are old enough to feed for themselves, they are on their own.

• Parental Investment
• no parental involvement
• altricial altricial
• female parental care female parental care
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

Lifespan in Philippine tomb bats is not known, but it is likely that they live longer than ten years under ideal conditions.

Behavior

Philippine tomb bats are social members of Emballonuridae and roost in colonies of from 150 to 4,000 individuals. Males and females occupy different areas of roosting sites and each individual has a defined vertical territory. Philippine tomb bats remain in their roost relatively inactive until the same time everyday, around 20 to 25 minutes after sunset, when they the cave to feed.

Hunting territory is considerably larger than that of many other bat species. This is because T. philippinensis hunts high above the ground, traveling at high speeds.

Closely related species ( T. longimanus ) hibernate for short periods, but specific information for Philippine tomb bats is unavaiable. Seasonal hibernation is indicated by the accumulation of fat at certain periods of the year, but it is unconfirmed.

• Key Behaviors
• flies
• nocturnal nocturnal
• crepuscular crepuscular
• motile motile
• sedentary sedentary
• colonial colonial

Home Range

The size of the home range of T. philippinensis is unavailable.

Communication and Perception

Philippine tomb bats communicate and perceive their environment via echolocation. Though they have rather large and well-developed eyes, echolocation is the primary method that these bats use to locate, identify, and track prey as well as perceiving their environment and avoiding obstacles. By sending out short bursts of sonic and ultrasonic waves from their mouths, which then bounce off objects, these bats can efficiently move through their environment, even in the dark. There is new research that indicates that these bats also use echolocation to communicate with each other, but specific mechanisms are not yet known.

Detailed information on communication in Philippine tomb bats is unavailable. However, males are known to secrete a sticky substance during mating season which sticks to their beard. This substance likely contains pheromones or hormones, and so plays a role in chemical communication.

Although details are lacking, some tactile communication is undoubtedly of importance between mothers and their offspring, as well as between mates.

• Communication Channels
• tactile tactile
• acoustic acoustic
• chemical chemical

• Other Communication Modes
• pheromones pheromones

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• ultrasound ultrasound
• echolocation echolocation
• chemical chemical

Food Habits

Philippine tomb bats are insectivores, catching their prey while soaring fast and high above the canopy. Bats in the genus Taphozous forage at relatively high altitude and high speed, catching flying insects directly in their mouths, or by scooping them up with wing/tail membranes.

Philippine tomb bats cover more area while hunting, and do not concentrate on small areas like other bats. Philippine tomb bats, like other predators, follow their prey's movements to new hunting grounds. Seasonal changes in prey density also cause T. philippinensis to move to new hunting grounds.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• insects

Predation

Information on the specific predators is unavailable. Hawks and owls have been observed to prey on adult Philippine tomb bats and the vunerable young can fall victim to predatory birds, reptiles, mammals, and even large insects. Predation is reduced because they are most active at night and are able to avoid predators. Adults of Taphozous species are even harder to prey upon because they fly at such relatively high altitudes and speeds; generally only other flying animals can catch them. Philippine tomb bats are relatively light colored, but they forage around dusk when it is not yet completely dark.

Philippine tomb bats are often plagued by species-specific parasites that contribute to mortality.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Philippine tomb bats and other bats play an invaluable role in the ecosystem. Insectivorous bats consume millions of pounds of insects every year, helping to stop the spread of disease and limit crop damage.

Economic Importance for Humans: Positive

Farmers must deal with millions of dollars worth of crop damage per year, due to destructive insect species. Bats of the family Emballonuridae consume tons of insects per year, providing a natural solution to insect pest problems.

• Positive Impacts
• controls pest population

Economic Importance for Humans: Negative

There are no known adverse affects of Philippine tomb bats on humans. Like other bats, they can carry and transmit rabies.

• Negative Impacts
• injures humans
  • carries human disease
• causes or carries domestic animal disease causes or carries domestic animal disease

Conservation Status

Philippine tomb bats are not known to be threatened or endangered. They are not listed on any government or third-party watch list.

Additional Links

Encyclopedia of Life

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Arthur Wang (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

References

Altringham, J. 1996. Bats: Biology and Behavior . Oxford, England: Oxford University Press.

Corbet, G., J. Hill. 1992. The Mammals of the Indomalayan Region: A Systematic Review . England: Oxford University Press.

Erickson, J. 2002. The influence of regional climate and nightly weather conditions on activity patterns of insectivorous bats. ACTA Chiropterologica , 4/1: 17-24.

Flannery, T. 1995. Mammals of the South-West Pacific & Moluccan Islands . Australia: Reed Books.

Heaney, L., D. Balete, M. Dolar, A. Dans, P. Gonzales, N. Ingle, M. Lepiten, W. oliver, P. Ong, E. Rickart, E. Tabaranza, R. Utzurrum. 2002. "Taphozous melanopogon" (On-line). A synopsis of the Mammalian Fauna of the Philippine Islands. Accessed August 09, 2004 at http://www.fmnh.org/philippine_mammals/Taphozous_melanopogon.htm .

Lekagul, B. 1977. Mammals of Thailand . Thailand: Kurusapha Ladprao.

Nowak, R. 1997. "Tomb bats" (On-line). Walker's Mammals of the World Online. Accessed March 31, 2004 at http://www.press.jhu.edu/books/walkers_mammals_of_the_world/chiroptera/chiroptera.emballonuridae.taphozous.html .

Payne, J. 1985. A Field Guide to the Mammals of Borneo . Kuala Lumpur: The Sabah Society.

Prater, S. 1965. The Book of Indian Animals . India: Bombay Natural History Society.

Schober, W. 1984. The Lives of Bats . England: Croom Helm.

Sedlock, J. 2001. Inventory of insectivorous bats on Mount Makiling, Philippines, using echolocation call signatures & a new tunnel trap. ACTA Chiropterologica , 3/2: 163-178.

Singh, U., A. Krishna. 2002. Seasonal Changes in Circulating Steroid Concentration and Their Correlation With the Ovarian Activity in the Female Indian Sheath-Tailed Bat, Taphozous longimanus. Journal of Experimental Zoology , 292: 384-392.