By the time summer rolls around each year, Taiwan’s numerous bat species have shaken off the last of their hibernation torpor and entered a period of frenetic activity. Accordingly, this is a time of great excitement for the nation’s community of bat conservationists, researchers and watchers, who spend the months from June to August carrying out a wide variety of projects, ranging from ecological studies and public education initiatives to domestic and international tourism programs.
In June this year, for instance, the Bat Conservation Society of Taipei (BCST) arranged for a group of around 20 parents and children to go on a four-day trip to Hong Kong and Macau to observe the flying mammals and learn about local protection efforts. During the same month, members of the Bat Study and Conservation Group of Japan visited a facility dedicated to the Formosan golden bat in southern Taiwan’s Yunlin County. “It’s the first time the Japanese group’s annual bat-watching event has taken place overseas,” notes Lee Ling-ling (李玲玲), a professor in the Institute of Ecology and Evolutionary Biology at National Taiwan University in Taipei and head of the Bat Association of Taiwan (BAT), which co-organized the visit.
Exchange programs such as these are part of growing efforts to increase public understanding of and protect the creatures. The Formosan Golden Bat’s Home, which was established in 2009 on the campus of Chengzheng Elementary School in Yunlin’s Shuilin Township, performs both these functions. The facility was founded by Chang Heng-chia (張恆嘉), a teacher at the school and member of the BAT, with the aim of preserving the endemic species of mouse-eared bat.
In 2012, with the help of other organizations such as the Endemic Species Research Institute under the Cabinet-level Council of Agriculture (COA), Chang organized the International Bat Symposium at Chengzheng to mark the 150th anniversary of bat research in Taiwan. The forum, which was attended by scholars and government officials from Australia, Japan, New Zealand, South Korea and Sweden, traced the first records of the Formosan golden bat and other native species back to an article released in 1862 by British naturalist Robert Swinhoe (1836–1877) about mammals found on the island.
Formosan tailless leaf-nosed bats, an endemic species, roost in a cave. (Photo courtesy of Hsu Chao-lung)
Worldwide, there are approximately 1,200 species of bat. Taiwan and its outlying islands are home to nearly 40, over half of which are endemic. This abundance of native varieties, Lee explains, is a result of Taiwan’s varied climate and topography. Due to the island’s diverse range of ecological environments, the creatures “do not have to go on long-distance seasonal migrations in search of food or hibernation spots,” the professor notes.
BCST secretary-general Hsu Chao-lung (徐昭龍) points out that Taiwan has around the same number of bat species as Japan, a nation 10 times larger in size. It also has a higher density of bat species than Europe and North America, he notes, adding that while rodents are the largest order of mammals globally, Taiwan has more species of bats than of any other mammal. “For these reasons, the island can justifiably be called a kingdom of bats,” Hsu says.
Lee notes that the nation has yet to conduct comprehensive surveys to establish the population sizes of its various indigenous bat species. While efforts are ongoing, progress has been slow as studying the nocturnal creatures poses challenges for scientists, requiring them to work lengthy hours at night and often in inaccessible locations like caves and tunnels, she says.
Thus far, Lee and other local researchers have determined that there are very limited numbers of at least two of the island’s endemic species—the Formosan flying fox and Formosan tailless leaf-nosed bat. As a result, the COA has listed these species as endangered and rare, respectively, and granted them protected status under the Wildlife Conservation Act. The frugivorous Formosan flying fox is the largest bat species in Taiwan, with an average wingspan of around 1 meter. In contrast, the insectivorous Formosan tailless leaf-nosed bat, one of the nation’s smallest species, has an average wingspan of just 16 centimeters.
Lee points out that bats play essential ecological roles as frugivorous species help pollinate flowers and disperse fruit seeds, while insectivorous bats assist with pest control since they consume significant quantities of mosquitoes, moths and other flying insects. Similarly, Hsu notes that bats provide economic benefits to the agricultural industry as their presence can reduce spending on pesticides in farmland areas, and bat dung is used as a fertilizer.
Three Formosan tube-nosed bats roost in a tree hollow. (Photo courtesy of Hsu Chao-lung)
The amount that bats contribute to the economy “equates to billions of dollars each year in the United States, not counting the money brought in by bat-watching attractions like the Congress Avenue Bridge in Austin,” the secretary-general notes. Each spring, Mexican free-tailed bats migrate from central Mexico to roosting sites in southern regions of the United States, including the bridge in Texas. “On spring and summer evenings, crowds of people gather to watch large swarms of bats emerge from under the structure,” Hsu explains.
Taiwan’s BAT, which was established in 2004 to promote the study and conservation of the mammal, has in recent years begun helping local government agencies manage some of the island’s bat-watching sites. In summer months, the group advises on boat trips with bat-watching components into the Moon Cave, which is located in Hualien County’s Fengbin Township and is part of the East Coast National Scenic Area. The BAT also offers recommendations to officials on tourism activities near several caves and tunnels in Chiayi County’s Alishan National Forest Recreation Area in southern Taiwan.
“If a cave is big enough for tourists to enter, we work with local officials to reduce the amount of noise and light generated by visitors so as to avoid disturbing the bats too much,” Lee says. “If it’s a small cave, we suggest that tourists not be allowed to go inside, but rather be encouraged to enjoy the sight of bats flying out of the cave at dusk.” Another approach is available for tourists in Alishan. The recreation area’s visitor center shows a live feed from cameras installed in a nearby cave, enabling tourists to observe some of the region’s bats.
The BAT is also actively involved in conservation programs, including working with local government officials to protect Taiwan’s largest cave-dwelling bat colony, which finds shelter near the island’s northeastern coast in New Taipei City’s Ruifang District from July to August each year. Since the early 1980s, Japanese long-winged bats have gathered in large numbers during the summer months near the district’s Ruibin Village. In addition to conducting regular surveys of the bats, the BAT is helping improve the area’s tourism operations. “We help the district office provide training to guides and volunteers about the proper way to conduct bat-friendly tours,” Lee says.
The growing interest in bat-watching is a result of determined efforts by local groups such as the BAT and BCST to change the misconception of bats as bloodthirsty creatures. “Of the world’s more than 1,000 bat species, just three feed on blood,” the professor notes. These vampire bats are found only in Central and South America.
Many of the window lattices at Baoan Temple in Taipei feature depictions of bats. (Photo by Huang Chung-hsin)
Hsu, meanwhile, notes that the bat has traditionally been seen as a positive symbol in Mandarin-speaking societies as the term fu, a common abbreviation for the animal from the full expression bian fu, shares the same pronunciation as the word for “fortune” or “happiness.” In Chinese culture, bats represent good fortune and well-being and therefore are a common motif for architectural embellishments in places of worship. “If you look carefully, you’ll likely be able to spot a depiction of a bat the moment you enter a temple,” he says.
One of the major objectives of the BAT and BCST is to promote an image of bats as a valuable indicator of environmental health. To this end, the groups work with local and international governmental organizations to spread awareness of the important ecological role played by the creatures. As a partner organization of the United Nations Environmental Programme, the BCST disseminated information released by the intergovernmental agency for its two-year Year of the Bat campaign in 2011 and 2012. The Taipei-based group organizes regular educational courses and activities, such as classes to teach elementary school students how to build bat houses. The BCST also cooperates with local government agencies like Taipei City Government’s Animal Protection Office and Geotechnical Engineering Office on conservation and research initiatives, including working with officials to halt the improper felling or pruning of urban trees in order to preserve more tree hollows and bark cracks, which provide roosting spots for the mammals.
Lee notes that while misconceptions about bats remain prevalent, the situation is improving. As an example of this, the professor points out that road construction and maintenance authorities such as the Taiwan Area National Freeway Bureau have in recent years conducted surveys on the distribution of bats and redesigned spaces inside culverts and under bridges to make them more suitable for roosting. These efforts are emblematic of the shift in policy toward the once-maligned creatures. “Such projects would have been inconceivable in previous decades,” Lee says.
Write to Pat Gao at cjkao@mofa.gov.tw