Liang Chieh-te, who has loved animals since childhood, is one of Taiwan’s leading makers of documentary films about birds and ecology. (photo by Lin Min-hsuan)
In April, fog comes and goes around the five main islands of Matsu, and sea mists often force the closure of the airport or cause takeoffs and landings to be delayed. But this is precisely the time of year when many bird lovers choose to visit Matsu. Their goal is to see a fowl that has come to be called “a bird of myth and legend”: the Chinese crested tern.
The bird known to scholars and birdwatchers as the Chinese crested tern (Thalasseus bernsteini) was first discovered for science by the German biologist Hermann Schlegel in Indonesia in 1863. In 1937 the Chinese zoologist Shaw Tsen-hwang collected 21 specimens of this creature on Shandong’s Muguan Island. But thereafter, except for a small number of sightings in China, Hong Kong, Thailand, and the Philippines, it was as invisible as the unicorn, leading some scholars to suggest it had gone extinct.
The “bird of legend” appears in Matsu
In 2000 Liang Chieh-te, who has made a number of well-known nature films including Fairies on the Pond and Fly, Kite Fly, was invited by the Lienchiang County Government to go to Matsu and make a documentary about terns. Liang usually shoots on 16-millimeter movie film, and due to a reel of film on which there was a problem with exposure correction during processing, he was able to notice some Chinese crested terns mingled in among thousands of greater crested terns (Thalasseus bergii), which are very similar in appearance to the Chinese crested tern.
Because there had been no reliably confirmed sightings of the Chinese crested tern for over 60 years, this extremely rare species was given another sobriquet—“the bird of myth and legend”—by bird expert Lucia Liu Severinghaus, formerly a research fellow at the Academia Sinica. Scholars estimate that there are only about 150 Chinese crested terns in existence. The species is listed as critically endangered on the Red List of Threatened Species of the International Union for Conservation of Nature (IUCN), and in Taiwan it is designated a “Type 1 protected species” (“endangered”).
Habitat destruction threatens survival
Since the dramatic rediscovery of the Chinese crested tern, not only have birders flocked to see this species, international ornithologists also have seen it as an important subject of research. A research team led by Yuan Hsiao-wei, a professor in the Department of Forestry and Resource Conservation at National Taiwan University (NTU), has been following issues related to the Chinese crested tern for many years. Yuan explains that species listed as critically endangered by the IUCN mostly have certain characteristics. First, they are “colonial breeders,” which is to say that they are “animals that habitually congregate together in colonies to reproduce, which is like putting all their eggs in one basket.” Second, they are migratory. “Long-distance migration increases risks to species’ survival, as relocation requires physical endurance, and natural disasters like hurricanes and typhoons can kill these animals.” The Chinese crested tern is both a colonial breeder and a migratory species.
At present Chinese crested terns are known to be breeding in only five places: Matsu and Penghu in Taiwan, the Jiushan and Wuzhishan Archipelagos in China’s Zhejiang Province, and Chilsando in Yeonggwang County, South Korea. Scholars have surmised that Chinese crested terns’ natural breeding grounds should probably be in more northerly latitudes, such as around the Bohai Sea. However, high levels of development and environmental pollution have degraded the islands, reefs, and beaches they depended on for survival, so that their geographical range of activity has been compressed southward. “Places where Chinese crested terns are recorded as breeding, such as Matsu and Penghu, are probably at the extreme southern end of their range,” says Yuan.
Scholars are also concerned because the Chinese crested tern is not a prolific breeder. In order to prevent the extinction of this species, it has become essential for humans to intervene to help it breed successfully.
Professor Yuan Hsiao-wei of NTU leads a research team that has studied the Chinese crested tern for many years. (photo by Lin Min-hsuan)
Decoys to the rescue
In the short term, the extinction of any given species has no effect on people’s daily lives. But in the long term, extinctions are definitely harmful.
To try to avert the demise of the Chinese crested tern, ten years ago, drawing on the experience of Cornell University, researchers adopted the technique of using decoys to attract the birds, an approach that has long been practiced overseas. Researchers choose a specific breeding area on an island and seek to attract the terns there. They then patrol the area to protect the birds in hopes of increasing their reproductive success, while also observing them to learn more about the species’ characteristics.
Each year, before the terns arrive, researchers and volunteers first go to Matsu’s Tiejian Island to clean up the environment. They pull weeds, remove predators, and set up video cameras and audio recorders. They also set out decoy birds made from polyester fiber and broadcast bird calls, aiming to attract terns to the island.
When large numbers of greater crested terns arrive, usually there will be some Chinese crested terns among them. At this special time, ordinary citizens and fishermen are banned from setting foot on the island, while research work goes into high gear. Volunteers must report back each day on the number of birds and their breeding status, and respond to any situations that may arise.
Birds today, humans tomorrow
The newly rediscovered Chinese crested tern has achieved star status internationally. Governments not only in Taiwan but also in China and South Korea have designated a number of uninhabited islands where the terns breed as protected areas. In order to better understand the biology of this species, researchers routinely share information and try to stay up to date on the birds’ migration routes and distribution.
However, it is not enough to act simply at the academic level: ecological protection is also vital, and everyone must do their part. In 2008, when a Chinese crested tern was photographed with a plastic bottle stuck on its beak, the incident sparked widespread discussion not only among birdwatchers but also among the public at large. This heartbreaking image testified to the damage being done to the natural environment, and we are all duty bound to help solve problems like the exhaustion of fisheries resources and the ever-increasing amounts of trash in the ocean. “There are many reasons why a species can become endangered,” says Hung Chung-hang, a postdoctoral research fellow in NTU’s Department of Forestry and Resource Conservation.
“Sooner or later the earth will hit back. Climate change is already here in our generation, and the same goes for marine pollution,” warns Yuan Hsiao-wei, adding forcefully, “What is happening to birds today will happen to humanity tomorrow.” Arthur Chiang, deputy executive director of the Wild Bird Society of Taipei, offers a similar admonition: “In the chain of life, birds are high-level predators, and the extinction of a bird species will bring dramatic changes to the entire food chain below it.”
However, protecting migratory species has always been difficult compared with protecting resident birds, which stay in one place year round. “Migrating birds don’t recognize national boundaries, and their wintering grounds, breeding grounds, and the places they stop over during their migration can all be in different countries. If conservation efforts are confined to just one of those countries, the impact will be limited,” says Yuan. Nevertheless, the situation is not hopeless for the Chinese crested tern. Take for example the black-faced spoonbill, which famously winters in Taiwan: At one point its total population had declined to about 500 birds, but thanks to cooperation among a number of nations that signed and respected the “Action Plan for the Black-faced Spoonbill Platalea minor,” its population has in recent years climbed back up to nearly 5000 birds. This success has brought much praise for Taiwan, which is the black-faced spoonbill’s main wintering ground, as well as an International Conservation Achievement Award from BirdLife International.
On a positive note, although the precarious situation of the Chinese crested tern highlights the urgency of addressing environmental destruction, at the same time it hints at the inseparable bonds between humans and animals. Besides reawakening people’s love for nature, it reminds us that as children of Planet Earth, we all have responsibilities. While “bird of myth and legend” is a beautifully poetic description, it also reflects the importance of this fateful moment in time. The key to transforming crisis into opportunity is often simply a change of heart among humankind.
For more pictures, please click《A Path to Survival: Conserving the Chinese Crested Tern》
