2025-3-4
Esther Tseng /photo by Jimmy Lin /tr. by Phil Newell
Courtesy of Taiwan Panorama February 2025

 

The eastern grass-owl, with its alert eyes, has an impressive appearance defined partly by the coffee-colored markings on its wings. Yet despite its majestic form, it is a bird of prey that needs our protection. (courtesy of Hong Shiao-yu)
The eastern grass-owl, with its alert eyes, has an impressive appearance defined partly by the coffee-colored markings on its wings. Yet despite its majestic form, it is a bird of prey that needs our protection. (courtesy of Hong Shiao-yu)


“Oh, how adorable!” We look at photos of a black-winged kite (Elanus caeruleus) moving its head from side to side as it roosts on one of a number of perches for raptors (birds of prey) set up by farmers amid their fields. Two other black-winged kites are wheeling through they air, playing musical chairs for a spot on the perches. Meanwhile, an eastern grass-owl (Tyto longimembris pithecops) carries a small rodent that it has caught directly to one of the perches.


The Bird Ecology Lab at National Pingtung University of Science and Technology has been using artificial perches for bird studies since 2017, and thus far has photographed 20 raptor species across Taiwan, as well as 70 species of non-raptor birds, accounting for virtually one-third of all Taiwan’s bird species. This demonstrates the biodiversity in farmland habitats.


However, these perch cameras—the world’s first—are not meant simply to be used to gather data on Taiwan’s bird species. Instead, they are used in combination with the ecological payments program of the Forestry and Nature Conservation Agency of the Ministry of Agriculture (MOA) to promote conservation of birds of prey like the eastern grass-owl. The program’s most important goal is to encourage farmers to take up organic or eco-friendly farming and so make a contribution to protecting endangered raptors.

 

There are three benefits to setting up raptor perches equipped with cameras: First, they help the birds catch rodents, reducing damage to crops. Second, they enable farmers to know what kinds of birds are active in their fields. Third, they collect data on the range of eastern grass-owl populations.
There are three benefits to setting up raptor perches equipped with cameras: First, they help the birds catch rodents, reducing damage to crops. Second, they enable farmers to know what kinds of birds are active in their fields. Third, they collect data on the range of eastern grass-owl populations.


The truth behind a tragic tale

In fact, behind the artificial perches program there is a tragic tale.


More than three decades ago a high-school teacher named Shen Chen-chung, also known as “Mr. Hawk,” became concerned about the black kite (Milvus migrans), which was facing extinction due to habitat loss. At the time, no one knew why large numbers of black kites were disappearing. It became a riddle that had to be solved in order to provide a starting point for their conservation.


The Bird Ecology Lab undertook a banding and tracking study of black kites, and their findings showed that most black kites were dying in farm fields.


Necropsies revealed that the kites were dying of internal hemorrhaging. Hong Shiao-yu, a post-doctoral researcher at the Bird Ecology Lab, remarks that black kites are scavengers, meaning that they eat carrion—the carcases of dead animals. Farmers were using rat poison and large amounts of the pesticide carbofuran to prevent damage to their crops by field mice. Black kites ate the carcasses of poisoned mice, thereby becoming the birds of prey most severely affected by agrochemical toxins.


Large numbers of black kites disappeared from Taiwan in the 1980s, until at one point there were only 200 remaining. However, thanks to initiatives by Shen Chen-chung and his successor, Lin Hui-shan (known as the “Hawk Princess”), in 2015 the Animal and Plant Health Inspection Agency of the MOA terminated “national rodent eradication week” and thereafter stopped subsidies for rat poison. Meanwhile, private businesses developed a natural rodent killer made from corn stalks: When the field mice eat it, their intestines become blocked and they die from bloating. As a result, black kites eating rodent carcasses no longer die from toxins. In addition, high-concentration carbofuran was banned as a pesticide in 2017, and the black kite population has gradually risen.

 

Fruit farmer Li Shuping (center) set up a raptor perch on her land, and has gotten images of the black-winged kite and the blue rock thrush. She shares the photos with visitors and with her adoptive parents in Germany.
Fruit farmer Li Shuping (center) set up a raptor perch on her land, and has gotten images of the black-winged kite and the blue rock thrush. She shares the photos with visitors and with her adoptive parents in Germany.


Farmland into wildlife habitats

Hong Shiao-yu says that farmers have been accustomed to conventional thinking whereby pesticide use is obviously the simplest method. But he always believed there must be a better way. For example, farmers can use mechanical seed drills to plant seeds into the soil rather than scattering them on the surface by hand, so that wild birds cannot eat them. Also, they can use advanced cultivation methods like greenhouses or bagging to minimize harm to avians.


“As farmers change their methods, they are also changing their mindsets, so that farmland is no longer just for growing crops but also has ecological conservation functions.” Protected lowland species like the eastern grass-owl, the leopard cat, and the emerald green treefrog all live on farmland, and the pangolin is active in foothills. Hence, farmland and mountain forests are all important wildlife habitats.

 

Farmers regard lalang grass as a weed and remove it from their fields. However, the grass also happens to be the eastern grass-owl’s favorite habitat. It is very soft and when it grows densely it forms layers that act as a roof, keeping out wind and rain. For eastern grass-owls that take shelter beneath it the grass is like a thatched cottage. (courtesy of Hong Shiao-yu)
Farmers regard lalang grass as a weed and remove it from their fields. However, the grass also happens to be the eastern grass-owl’s favorite habitat. It is very soft and when it grows densely it forms layers that act as a roof, keeping out wind and rain. For eastern grass-owls that take shelter beneath it the grass is like a thatched cottage. (courtesy of Hong Shiao-yu)


A better way

Tyto longimembris pithecops, Taiwan’s endemic subspecies of the eastern grass-owl, is a Category I protected species (“endangered”). It is the only bird of prey that prefers to live in grassland and brushland rather than forest. This bird, with its radiant and vivacious eyes, is also facing threats to its survival including habitat loss and poisoning by rodenticides.


How can rodents be controlled without using poison? Professor Suen Yuan-shiuan, head of the Bird Ecology Lab, proposed providing perches as a biological control method. Taking advantage of the fact that birds of prey prefer high places, farmers can erect elevated artificial perches in their fields to attract raptors to come and catch rodents on their farms.


Hong Shiao-yu consulted foreign scientific literature and discovered that in most Western countries owl nest boxes are set up on farmland to encourage the birds to hunt rodents there. However, Taiwan is the first place in the world where cameras have been installed on artificial perches.


“Before I began doing this research, I had never seen an eastern grass-owl. I had only heard of them, and there were very few of them, so I didn’t know where to look for them.” For Hong, eastern grass-owls were virtually mythical creatures. But it wasn’t long before images of an eastern grass-owl (known in Taiwanese as the “monkey-faced owl”) were captured by a camera on a manmade perch beside the Gaoping River.

 

The Bird Ecology Lab at NPUST has been using artificial perches as a research tool since 2017 and thus far has photographed 70 species of non-raptor avians across Taiwan.(courtesy of Hong Shiao-yu)
The Bird Ecology Lab at NPUST has been using artificial perches as a research tool since 2017 and thus far has photographed 70 species of non-raptor avians across Taiwan.(courtesy of Hong Shiao-yu)


Ecology and conservation

As a result of his research, the Forestry and Nature Conservation Agency announced in 2022 that the eastern grass-owl would be a focal point of its conservation measures for endangered species. Since then, the MOA and the Taiwan Biodiversity Research Institute have brought together 24 relevant organizations to form an interagency alliance for grass-owl conservation. Moreover, the MOA has included the eastern grass-owl along with other endangered species such as the leopard cat in its ecological payments program.


With regard to endangered birds of prey, any farmer whose crops are shorter than the height of an artificial perch can apply to put up raptor perch and can collect NT$3,000 in maintenance fees. There is also an incentive payment of NT$10,000 per year for any farmer whose perch camera captures a photograph of an endangered raptor.


When farmers first put up artificial perches in their fields they are skeptical that they will attract birds of prey. But Xinchang Ecological Research Ltd., which was commissioned to evaluate the effectiveness of the program, states that about two-thirds of farmers end up with photographs of raptors, meaning that the odds of getting the incentive money are high.


Hong Shiao-yu relates that when images are collected from the perches, there are often wonderful surprises. For example, in Chishang, Taitung County, a photograph was taken of an ortolan bunting, which was only the second recorded sighting of this bird in Taiwan and the first time it was caught on camera. Ortolan buntings were once a widely consumed if controversial delicacy in France, where they are now protected. This individual bird probably lost its way before arriving in Taiwan.


To encourage more farmers to engage in eco-friendly agriculture, several years ago Lin Hui-shan began working with the PX Mart supermarket chain to market adzuki beans grown using eco-friendly farming methods with an eye to black kite conservation, under a special label. After getting a very positive response from consumers, she successively got PX Mart to also put “black-winged kite rice” and “owl pineapples” (grown in Pingtung in coordination with protection of the collared scops owl) on its shelves. At present she is planning to come out with a certification mark for conservation of the eastern grass-owl. In these ways farmers can make a good living while birds of prey become their eco-friendly partners, to the benefit of both.

 

Lin Hui-shan (left) is working with farmers from Gaoshu Township in Pingtung County to promote the sale of “owl pineapples” (grown in coordination with protection of the collared scops owl) through the PX Mart supermarket chain. (courtesy of Lin Hui-shan)
Lin Hui-shan (left) is working with farmers from Gaoshu Township in Pingtung County to promote the sale of “owl pineapples” (grown in coordination with protection of the collared scops owl) through the PX Mart supermarket chain. (courtesy of Lin Hui-shan)