Geographic Range
The type locality of black-eared flying foxes is the Nicobar Islands in India. They
are found throughout many islands in Southeast Asia, including the Andaman Islands
in India, the Engano and Nias Islands in Indonesia, and Christmas Island, south of
Java.
- Other Geographic Terms
- island endemic
Habitat
Pteropus melanotus
is generally found in forests and swamps on small, oceanic islands. They roost in
rainforest trees on these islands.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- rainforest
- Wetlands
- swamp
Physical Description
Black-eared flying foxes have dark brown to black fur, except in the chest and neck
region where the fur is light brown. The genus
Pteropus
includes the largest bat species in the world. No records of body measurements could
be found in the literature. Males of
Pteropus
species tend to be larger than females and species range in size from 170 to 406
mm in body length and 610 to 1,700 mm wingspan.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Reproduction
There is no information on the mating systems of black-eared flying foxes. In many
species of
Pteropus
males form mating harems during temporary breeding aggregations.
Little is known about the reproductive behavior of
Pteropus melanotus
except that breeding occurs once a year, and February tends to be the peak birthing
time.
Pteropus melanotus
individuals reach sexual maturity in only six months, less than any other
flying fox
species which generally reach sexual maturity in 18 to 24 months.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
Black-eared flying fox females nurse and care for their young until they reach independence.
In most
Pteropus
species, females carry their young for the first few weeks after birth. Subsequently
they leave the young in a roost while foraging, returning to nurse them.
Pteropus
species young generally become independent 2 to 3 months after birth.
- 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
Other
Pteropus
species have record life spans around 25 to 35 years, but there is no specific information
on
P. melanotus
.
Behavior
Black-eared flying foxes are one of the few species of bats that are active during
the day. They tend to roost in groups of several hundred bats, and during the day
can be seen flying in large groups in updrafts near cliff faces.
Home Range
Home ranges of black-eared flying foxes are unknown.
Communication and Perception
Black-eared flying foxes use their keen vision in low light to navigate. They also
use olfaction to find fruits and communicate reproductive status.
Food Habits
Black-eared flying fox diet consists mainly of fruits and blossoms of rainforest trees.
They tend to favor
Muntingia calabura
, which is an introduced Japanese cherry.
- Plant Foods
- fruit
- flowers
Predation
Domestic cats (
Felis silvestris
) are the main predators of
Pteropus melanotus
on Christmas Island, making up 21 percent of their diet by weight. Humans also eat
Pteropus
species. They may also be preyed on occasionally by birds of prey and arboreal snakes.
They avoid predation mainly through communal roosting in tall trees.
Ecosystem Roles
Black-eared flying foxes help to disperse fruit tree seeds and fertilize areas around roost trees.
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
Black-eared flying foxes are important members of their native ecosystems, they are especially important for dispersing tree seeds.
Economic Importance for Humans: Negative
Black-eared flying foxes sometimes eat fruit and may impact fruit crops.
- Negative Impacts
- crop pest
Conservation Status
As of 1996
Pteropus melanotus
was placed on low risk or least concern on the IUCN Red List. There is a limited
number hunted by natives. However, there are concerns that black-eared flying foxes
are especially vulnerable because of their restriction to small, oceanic islands and
their apparent lack of fear of humans. Black-eared flying foxes also tend to be active
during the day, making them easier to hunt than other species of
Pteropus
.
Other Comments
Most of the information that was found is on the subspecies
P. m. natalis
, with little information on the other five subspecies.
Additional Links
Contributors
Tanya Dewey (editor), Animal Diversity Web.
Kyle Steiner (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- island endemic
-
animals that live only on an island or set of islands.
- 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.
- 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.
- 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.
- 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.
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- diurnal
-
- active during the day, 2. lasting for one day.
- 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.
- colonial
-
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
- visual
-
uses sight to communicate
- 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
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- herbivore
-
An animal that eats mainly plants or parts of plants.
- frugivore
-
an animal that mainly eats fruit
References
McNab, B., M. Armstrong. 2001. "Journal of Mammalogy" (On-line). SEXUAL DIMORPHISM AND SCALING OF ENERGETICS IN FLYING FOXES OF THE GENUS PTEROPUS. Accessed December 01, 2006 at http://www.bioone.org/perlserv/?request=get-document&doi=10.1644%2F1545-1542%282001%29082%3C0709%3ASDASOE%3E2.0.CO%3B2 .
Nowak, Ronald M, 1999. Walker's Mammals of the World . Baltimore: Hopkins University Press.
Tidemann R, 1994. The Diet of Felis catus on Christmas Island, Indian Ocean. Wildlife Research , 21/3: 279-286.
Wilson, R. 1993. Mammal Species of the World . Washington: Institution Press.
2002. "Aging Cell" (On-line). Life history, ecology and longevity in bats. Accessed December 01, 2006 at http://www.blackwellpublishing.com/products/journals/suppmat/ACE/ACE020/ACE020sm.htm .
1998. "Australian Biological Resource Study" (On-line). Australian Government: Department of the Environment and Heritage Home Page On the World Wide Web. Accessed November 03, 2006 at http://eriss.erin.gov.au/cgi-bin/abrs/fauna/details.pl?pstrVol=EUTHERIA;pstrTaxa=140;pstrChecklistMode=2 .
1999. "Australian Biological Resource Study" (On-line). RECOVERY OUTLINES AND TAXON SUMMARIES - Christmas Island Flying-fox. Accessed December 01, 2006 at http://www.deh.gov.au/biodiversity/threatened/publications/action/bats/31.html .
1999. "Australian Museum Online" (On-line). Bats in Australia: Christmas Island Flying Fox. Accessed November 03, 2006 at http://www.austmus.gov.au/bats/records/bat7.htm .
2006. "Christmas Island" (On-line). Mammals. Accessed December 01, 2006 at http://www.abc.net.au/nature/island/ep2/locals/4.htm .
1996. "UNEP-WCMC Species Database" (On-line). Accessed November 03, 2006 at http://sea.unep- wcmc.org/isdb/CITES/Taxonomy/tax-species-result.cfm?Genus=Pteropus&Species=melanotus&source=animals&tabname=status .
Michigan Science Art. 2002. "University of Michigan Museum of Zoology: Animal Diversity Web" (On-line). Pteropus (flying foxes). Accessed November 03, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/pictures/Pteropus.html .