Indian Flying Fox (Pteropus giganteus) is one of the largest flying fox bat species found on the Indian subcontinent with Nepal being part of its range and distribution. Generally found in habitats of tropical forests and woodlands, these fruit-eating bats are fairly common across Nepal's lower tropical belt, particularly the Tarai plains which are forested. They play an important role in the seed dispersal of tropical fruit plants. The bats also symbolize rebirth in Hindu-Buddhist beliefs in Nepal.
Key Facts about the Indian Flying Fox
- The bats are quite large, with an average wingspan typically ranging from 4 to 5 feet (1.2 - 1.5 m). Their bodies usually measure 2 feet long (about 60 cm), weighing around 1 kg.
- They have a grey-colored coat of fur along velvety flaps. There's reddish fur around the neck and shoulders. Their faces are pale with well-defined muzzles and pointed ears. Wings consist of leathery, brownish membranes.
- During hot days, roost in trees by hanging upside down on their feet. However, at night, form massive colonies of up to a thousand bats that set out to forage on ripe fruit flesh. Their flight and sense of smell are highly robust.
- Social animals that live in tight-knit colony communities. Agile fliers are often falsely perceived as giant birds gliding overhead. Live rather long with longevity up to 15-20 years in the wild.
- Populations concentrated in the foothills of Sub-Himalayas, Chitwan riverbanks, and various places across 22 Terai protected areas. They're classified as being a species of low conservation concern.
Indian Flying Fox bats are intriguing, often misunderstood species playing a vital role in keeping Nepal's tropical forests healthy and fertile. They are relatively common and ever-present in valley settlements as well as lower forest habitats.
Interesting Information
- Colonies choose day roosts in varieties of forest trees like mango, banana, pipal, banyan, etc. Their claws allow them to dangle perfectly camouflaged resembling dry leaves when resting. The loud squeaks of their social chatter however give away their location.
- Most active at dusk when entire colonies exit roosting sites to begin searching for food which mainly consists of ripe wild mangoes and figs. Their wings make distinctive flapping sounds audible from afar at the onset of night.
- Possess incredible olfactory senses guiding them over several kilometers towards fertile trees and orchards. Can consume over half their body weight in juicy fruits and nectar nightly given their high energy needs for flight.
- While foraging, often raid commercial mango orchards much to the annoyance of farmers. Their reputation subsequently varies from being worshipped as deities by some to being considered destructive pests by fruit growers facing losses.
- Large colonies congregate at select sites like Chitwan National Park where tall native trees offer ideal hosting spaces. The bats coexist peacefully alongside rhinos, tigers, and leopards within the protected grounds.
- Dusk bat flights make for a popular tourism spectacle in places like Chitwan temple where hundreds emerge simultaneously like a dark swirling cloud. Their aerobatics are mesmerizing though ear-piercing to stand directly underneath!
- They play a key ecological role in seed dispersal and pollination. When feasting on fruits, the bats ingest seeds spreading them far via defecation allowing more trees to sprout across forests. Their fur also carries flower pollen aiding cross-pollination.
- The bats exhibit loyalty to their colony and roosting sites, typically not abandoning them unless facing threats like habitat destruction. Some colonies can grow to number over 5,000 members with intricate social structures.
- Baby bats called pups cling onto their mothers during night flights, even as mothers exhibit mid-air acrobatics. After a few weeks, the pups learn to fly solo under elders' guidance. Female bats produce only one offspring annually.
- Have lifespans of over 20 years in captivity though face threats from hunting, electrocution on power lines, and entanglement in fruit nets. Their populations however remain quite thriving. They are considered "reservoir species" with antibodies to many viruses.
- Beliefs hold them sacred as vehicles of Lakshmi, the goddess of wealth and prosperity. Hence killing them is taboo. Farmers near roosting grounds lure colonies to orchards for bountiful pollination by leaving offerings of sweet bat treats!
- Dusky silhouettes gliding overhead near temples and over rivers by dusk often symbolize departed souls being released signaling new beginnings. Hence they are believed to represent triumph over death.
Breeding Habits
- Breeding season is from March to April when loud buzzing mating calls can be heard near roosts as males compete to mate with females. The gestation period lasts 140-150 days.
- Mothers carefully groom babies born pink but rapidly sprouting black fur. Pups open their eyes at around 10 days old. Weaned by 2 months to fly solo under elders' guidance.
Threats and Conservation
- Face threats from roosting habitat loss and conflict with fruit orchard farmers. Electrocution on power lines near feeding grounds also poses a risk.
- Classified as 'Least Concern' on the IUCN Red List signifying stable populations for now. Around 183 roosting colonies identified so far across Nepal.
Coexistence with Humans
- Their ability to adapt to landscapes dominated by human agriculture and settlements allows peaceful coexistence in most cases.
- Some ingenious farmers have begun using smaller nets allowing bats entry while keeping out birds. They benefit from bats controlling insects and enhancing pollination minus losses.
Cultural Significance
Often depicted in stone carvings, paintings, and textiles across Nepal. Beliefs hold them as bridges between living and dead symbolizing spirits released after the mourning period passes, hence the cyclic nature of life.
Perception by Locals
Locals' views on them vary. Some indigenous Tharu tribes call them - 'kanjirowa' - holding them as sacred fertility symbols. Whereas migrant farmers consider them destructive crop raiders wanting them out of orchards.
Medicinal Beliefs
Folk medicinal beliefs especially among indigenous groups prescribe eating bats for asthma relief given their strong respiratory systems for flight. Their droppings/meat are smoked to cure various respiratory illnesses despite a lack of scientific basis.
Roosting Sites
Preferred large native trees like banyans and figs offer ideal dense cover, more so if near a water body for thirst-quenching after feeding. Colonies gravitate towards isolated trees providing clear airspace for exit/entry during flights.
Recent Research
Researchers from Tribhuvan University have placed tracking devices on some specimens to study flight patterns. The key goal is to quantify their seed dispersal contributions to tropical ecosystems by tracing droppings to emerging saplings.
Myths and Legends
An ancient legend tells of how the giant god Hanuman was transforming into bat form to fight demons when a biting fly distracted him. His torn-off waist part fell forming the hills below Kathmandu valley, as bats circled overhead.
Tourism Potential
Watching their synchronized dusk exits from colonies has untapped tourism potential. Safely regulated sites could allow observation towers for visitors granting them an educational experience minus disturbing flight paths.
Adaptability
As resilient and adaptive mammals, they likely will continue thriving in Nepal's changing landscapes if roosting sites are preserved. Their ability to fly vast distances aids their enduring survival across territories.
Research Priorities
Public health experts want to monitor specimens for pathogen spillover events given large colony sizes. Ecologists recommend tracking ecosystem services via mapping seed dispersal by analyzing genetic signatures from emerging saplings.
Future Outlook
Education and sustainable solutions for farmers facing losses can enable peaceful coexistence. Their vital pollination services dependency means locals revere them as harbingers of fertility and new life notwithstanding conflicts.
Migration Patterns
It is believed Indian Flying Foxes migrate seasonally across South Asia following fruit ripening cycles. Nepali colonies may interconnect with bats from Indian roosts with Himalayan valleys acting as migratory corridors during winter. Radio-tracking studies to validate migration theories are currently limited.
Climate Change Impact
Rising temperatures may allow mosquitoes, ticks, and other disease-carrying insects to thrive at higher altitudes thereby spreading to bats across mid-hills. Monitoring parasite loads in bat blood can assess if rising temperatures have expanded insects' habitat ranges.