Taiwan Today

Botanists are cataloging Taiwan’s native plants in a bid to protect threatened species.

Previous visitors to Taiwan are doubtless familiar with the blue hues of the NT$1,000 banknote issued by the country’s Central Bank. But they may not have noticed the small plant design tucked away on one corner of the bill. The image was originally thought to depict a Yushan thistle, an endemic plant named after Taiwan’s tallest mountain, but the designers were revealed to be mistaken thanks to a five-year research project. Led by Tseng Yen-hsueh (曾彦學), a plant expert at National Chung Hsing University in the central city of Taichung, the study found the thistle shown on the banknote differed subtly from the Yushan variant. In February 2019 the team declared the discovery of the Tataka thistle, adding to the nation’s many unique species.

“Correct taxonomy is vital to conservation efforts,” Tseng said. “All organisms have their place in the world. Our job is to try and protect them.”

Taiwan’s varied plant life makes it a natural research focus for scientists like Tseng. This abundance of flora is recorded in “The Red List of Vascular Plants of Taiwan,” a report published three years ago. Work on the list began in 2008, involving more than 50 academics from around the country who conducted the most thorough analysis of its kind to date, according to the Endemic Species Research Institute (ESRI) in charge of the project under the Cabinet-level Council of Agriculture (COA) in the central county of Nantou. The report employs the classifications from the Red List of Threatened Species created by Switzerland-based International Union for Conservation of Nature (IUCN), one of the leading organizations involved in protecting biodiversity around the world.

Nonvascular plants such as mosses, liverworts and algae were not part of the research, ESRI researcher Chang Ho-ming (張和明) said, because available information for such species is often insufficient to decide on conservation status.

Thriving Ecosystem

Taiwan’s red list reveals the country and its offshore islands are home to 4,442 native vascular plant species, about a quarter of which are endemic. This figure is high considering the nation’s relative size. According to ESRI, 122.7 of such species can be found in Taiwan for every thousand square kilometers, compared with 14.7 in Japan and less than 2 in the U.S.

The number has risen rapidly in the past 20 years—a preliminary survey in 2012 only recorded 4,174 species. This is thanks to a growing public interest in exploring local flora combined with widespread adoption of mobile devices, ESRI researcher Li Chiuan-yu (李權裕) said. “Modern technology means any enthusiast can capture high-quality images of a plant and send it for a professional to examine.”

After almost a decade of work, the Taiwan red list’s final tally includes 3,426 vascular species in the categories of lower concern including those lacking sufficient data, and a total of 27 species that are either “extinct in the wild” or “regionally extinct.” But it is the 195 classified as “critically endangered,” 283 “endangered” and 511 “vulnerable” that concern conservationists the most. Together these are deemed as threatened plants likely to go extinct if action is not taken, accounting for 22.3 percent of all species surveyed.

Taiwan has enacted several laws to protect local flora, including the Cultural Heritage Preservation Act promulgated in 1988 targeting specific plant varieties. Initially, 11 rare and endangered species were covered by the law, but seven have subsequently been removed from the list thanks to improvements in conservation techniques including habitat preservation and targeted breeding programs.

Of the threatened species identified on the red list, 89 percent can be found in places such as national forests, parks and nature reserves where they are protected by law. It is the remaining 11 percent, or 110 species, that demand the most urgent action, as they are often found co-existing with humans around suburban areas, roadside shoulders or rice paddy fields.

Proven Expertise

Taiwan has a positive record when it comes to saving plant species from extinction. The most recent success story involved replanting of the large purple orchid, a critically endangered variant found on Lanyu, also known as Orchid Island, and Green Island off the country’s southeastern coast. In 2013, ESRI began to collect seeds from some of the less than 50 large purple orchid plants remaining on Lanyu, where the population was in severe danger due to years of natural disasters and the orchid’s popularity among flower foragers. Researchers subsequently cultivated the species in controlled environments before introducing 500 new plants back into local ecosystems. Experts from the COA have also successfully bred varieties of the orchid that will soon be available for purchase. “It should reduce the risk of the flowers being taken from their natural habitats,” Li said.

This strategy is combined with efforts to protect both flora and fauna in biodiversity hotspots, said Huang Chium-tse (黃群策‬), director of the Forestry Bureau’s conservation division under the COA. “Protecting either benefits the other, as there’s a symbiosis between the two; plants provide food to animals whereas animals help spread plant seeds,” he added. Currently, the Forestry Bureau is overseeing 43 otherwise unprotected natural habitats around Taiwan.

One such area is terraced paddies and their surroundings in New Taipei City’s Gongliao District, totaling 6.4 hectares and home to more than 750 species including seven threatened plant varieties. To maintain the ecosystem, the Forestry Bureau commissioned the Environmental Ethics Foundation of Taiwan, a nongovernmental organization based in the northeastern county of Yilan, to encourage environmentally friendly farming practices among local farmers.

Foreign Invaders

Aside from working round the clock to protect local environments, the bureau is also keenly aware of the problem posed by highly invasive foreign species. A top target is the mile-a-minute vine, a native of Latin America included on IUCN’s list of the 100 worst invasive alien plant and animal species.

In the early 2000s, the government agency launched a monthlong national campaign to weed out the climbers starting in late summer every year prior to the plant’s reproductive cycle. The total area infested subsequently decreased by approximately 90 percent between 2001 and 2019, from 51,852 to 5,132 hectares.

Another major target is the white leadtree, a notoriously aggressive plant native to Central America and also on the IUCN list. Its leaves secrete mimosine, which inhibits the growth of other plant life. “Where they fall, nothing else can grow,” Huang said.

To stave off this threat, the Forestry Bureau has been working since the early 2000s to replace the  white leadtree with native species. Although the small, fast-growing tree can be found all over southern Taiwan, the majority of the agency’s resources have focused on the population around the Hengchun peninsula on the southernmost tip of Pingtung County, which is the only area in the country covered by tropical monsoon forest. No precise measurements of white leadtree coverage were made before the bureau’s work commenced, but today it stands at less than 5,000 hectares.

According to Huang, Taiwan’s red list is scheduled to be adjusted every four to eight years, based on the up-to-date IUCN standards as well as the most recent surveys of local flora. “By comparing results we can decide how effective our conservation efforts are and adjust policies to better protect threatened species,” he said. “Plants are a key component of the landscapes that shape national identity. They’re just as worthy of preservation as any cultural or historic landmark.” 

Write to Oscar Chung at mhchung@mofa.gov.tw