Conservationists and scholars are falling
under the spell of the firefly.
The intermittent light of the firefly can function something like an inkblot test, according to Ho Jen-zon, a scholar so fond of the insects that he is known to his colleagues as Dr. Firefly. Observers of the blinking bugs, he says, reveal their own proclivities and predilections--a scientist might focus on the frequency of the flashes; a musician, the rhythm; a painter, the color.
For many Taiwanese people, fireflies spark sweet memories of childhood and languid summer nights. "When I was little, on summer nights my family and I used to put a straw mat on the ground in front of our house and lie down to watch for fireflies," recalls the 64-year-old Ho Yuan-san, director of the Taiwan Endemic Species Research Institute (TESRI). "At that time, despite the lack of material affluence, we enjoyed rural life a great deal, especially seeing fireflies light up in the sky. That kind of beauty was just beyond description."
Part of the reason fireflies are associated with childhood for so many people, however, is that they are less often seen today. Taiwan is home to 62 of some 2,000 species worldwide, but the number of fireflies has dropped as their habitats have shrunk over the years. Dr. Firefly, Ho Yuan-san and others are working to reverse the trend through research, conservation and promotion of these pixyish night fliers.
According to Ho Yuan-san, TESRI, for example, is conducting an islandwide survey of fireflies, their habitats and other ecological factors to create a kind of databank that can be used by researchers and environmentalists. The institute also teams up with agricultural and tourism groups to rehabilitate the natural environment of fireflies and to promote ecological tours and firefly viewing.
He adds that government agencies, such as the Forestry Bureau, and private groups have been receptive to the conservation plans to preserve the habitats and breeding grounds of the firefly and to organize viewing. According to Ho Yuan-san, it is estimated that every year, the number of the domestic residents viewing fireflies has amounted to more than 1 million. "The magnificence of fireflies lighting up the sky can now be seen again in Taiwan's mountain areas," he says. "Hopefully, through the appreciation of such natural wonders, the general public can get to know the importance of conservation and pitch in."
Indeed, because of their spectral luminescence, so rarely seen in the everyday world, fireflies tend to be an easy sell. During the witching hours of dusk, fireflies, also known as lightning bugs, begin to glow in yellow, greenish yellow or orange hues. They can glow for half an hour to five hours at a time either continuously or intermittently. Different species blink for different lengths of time, like the dots and dashes of Morse code. And like Morse code, the flashes are used to communicate, sometimes as a warning to other fireflies and sometimes to catch the attention of a desired mate. Generally, species active in the spring and summer produce flashing lights, while autumn and winter fireflies tend to emit a continuous glow.
The light comes from the "lantern"--technically known as the photophore--located on the underside of the rear part of the abdomen. In the lantern, the chemical compound luciferin and the enzyme luciferase react with oxygen to produce light, which is directed and intensified by reflectors.
Ho Jen-zon, a researcher in TESRI's Zoology Division, points out that males have two lanterns, big eyes and a thinner body, whereas the females have only one lantern, small eyes and a fatter body. Even the larvae glow. Females lay eggs on moss, wet soil or among fallen leaves.
Fireflies have a life span of approximately one year, broken into four stages--the egg (20 days), the larva (10 months), the pupa (7 to 10 days) and the adult (2 to 3 weeks). They are remarkably adaptable, and different species can be found at different altitudes in Taiwan. Between April and June, they are more likely to be found in the plains and hilly areas, and from November to January it is best to seek them out in higher mountain areas.
Breeding patterns are similarly diverse. The larvae, the stage at which the firefly spends most of its life, are classified into three types based on their breeding environment--aquatic, semi-aquatic and terrestrial. Of Taiwan's 62 species identified thus far, 58 are terrestrial.
There is only one semi-aquatic species found in Taiwan, Pristolycus kanoi Nakane. It generally inhabits riverbanks and plucks its prey from the surface of the water. It is common in mountains of a low or medium altitude.
Aquatic species are only slightly more common; six have been identified worldwide. They live primarily in Asia, and three of them can be found in Taiwan--Luciola ficta Olivier, Luciola sp.and Luciola substriata Gorham.
Terrestrial breeders account for the majority of Taiwan's firefly species. Luciola cerata Olivier is the most common. Fireflies of this species dwell in low-altitude (under 1,500 meters) mountain areas. Only one species, Pyrocoelia analis (Fabricius), can be found in Taiwan's low-lying coastal plains. A trek into the mountains is required to catch a glimpse of the many other species on the island.
Firefly larvae also differ greatly in their eating habits. Since fireflies spend most of their lives in this stage of development, understanding the larvae's eating habits is helpful to understanding their relationship to the larger environment.
The wormy creatures feed in one of two ways--by eating decomposing bodies or by hunting live prey. Luciola anceyi Olivier, Luciola cerata Olivier and Luciola gorhami Ritsema, for example, consume the carcasses of arthropods and mollusks. As scavengers, they are nature's recyclers, transforming spent bodies into new life.
Other firefly species are less content to eat what they find, preferring instead to pick their dinner from among the living. Species such as Pyrocoelia praetexta Olivier, Luciola ficta Olivier and Lamprigera yunnana (Fairmaire), for example, attack ants, earth worms, shellfish, snails and other small arthropods by injecting them with a sort of digestive liquid that anesthetizes victims. Once the prey is immobile the firefly larvae go to work with their jawbones until the carcass is consumed.
By the time a firefly reaches adulthood, it leaves behind these carnivorous eating habits. In fact, the illuminating fliers consume a few droplets of dew or nibble on the pollen of flowers. Since they have lost their taste for flesh by adulthood, fireflies are commonly perceived as human friendly.
While fireflies might be friendly to humans, however, humans are encroaching on the habitats of the insects with harmful results. According to Ho Jen-zon, the environmental conditions for fireflies, especially aquatic species, are deteriorating. The development of waterways, the draining of wetlands, and the shrinking of terraced farms have left fireflies with few places to lay their eggs. He notes, however, that the aquatic species are in fact easier to cultivate in conservation projects, and it is quite possible to create the proper environments for breeding. He suggests that farmers might be encouraged to include fireflies in their eco-recreational farms, which are increasingly common in Taiwan.
In general, humans are threatening to the firefly's habitat. River pollution (often caused by factory waste), the use of pesticides and the development of once wild lands have resulted in fewer fireflies. Perhaps the most curious point of conflict between humans and fireflies is light. While people are often enchanted by the illuminated insects, the bugs are repelled by the artificial light created by humans. As cities and towns grow, therefore, fireflies move farther away to avoid the ambient light.
Scholars are still looking into the reasons for this curious phenomenon and trying to better understand the firefly's world. Ho Jen-zon says that 10 years ago almost no one was doing academic research on the firefly in Taiwan and academic resources were scarce.
Ho Jen-zon decided to devote his academic life to studying the firefly, first by writing his doctoral thesis on fireflies then working as a researcher at TESRI. He likens the search for new species and the investigation into the firefly's realm as "looking for a lantern in the dark." "The discovery of unidentified species, as well as the wonder of these light-emitting creatures make it all worthwhile," he says.
Today, he says, academic institutions, city and county governments, conservation groups and farmers' associations are all paying more attention to the firefly, and all the attention has allowed the firefly to become a public issue.
Yen Jen-teh, director-general of the Forestry Bureau, says his agency has been working closely with other groups, including TESRI and the Public Construction Commission, to help protect the habitat of the firefly. He is pushing for the adoption of ecological engineering methods for public works projects, such as channeling rivers and clearing mountain trails. Yen also points out that the fireflies help draw people to Taiwan's primitive forests and stimulate interest in the outdoors in general.
Indeed, some feel that the survival of the firefly is a good litmus test for overall environmental conditions. "If we can success fully save fireflies, that means we have protected the living environment of mankind as well," says Chen Jen-chao, vice chairman of the Firefly Conservation Association. "But if we fail to protect our environment, thus causing the gradual extinction of some creatures such as fireflies, we may eventually suffer the same fate."
Ever since its establishment in 1999, Chen's association has been striving to promote a better understanding of fireflies--their habitats, behavior and ecological significance--by organizing lectures, seminars and firefly-viewing activities, as well as publishing brochures and explanatory guides. "Education is key to the success of conserving nature," he emphasizes. "By launching educational campaigns, we hope to inform the public of the necessity of environmental protection and how they can contribute."
Given that the majority of fireflies inhabit the mountains, his association has also forged links with aboriginals living in remote highland areas. Chen is pleased to see so many people taking part in the various activities organized by his association.
Then again, fireflies have always had a way of casting a spell on humans, in part because they appear in the early evening just after the dinner hour when the day fades into night. They float like night spirits amid the darkness, rekindling a sense of wonder. "Hopefully," says Chen, "they will always illuminate our evening skies with their enchanting beauty."