Guanyinshan Raptor Museum

Welcome to Guanyinshan! To the east lies the Tamsui River, while on the west is the Taiwan Strait. You can experience both the mountains and sea while walking along the mountain trails here. Guanyinshan has vast forests and a rich ecology, which attracts predators at the top of the food chain, such as raptors. Here, you can observe Crested Serpent Eagles and Crested Goshawks all year round. In addition, Guanyinshan is located at the northern end of a mountain range and is the highest point in northwestern Taiwan. This special location makes the last stop for migrating raptors before they head across the sea as part of their northern migration in the spring. Generally speaking, Guanyinshan is an excellent place for raptor-watching in northern Taiwan with a great variety found here. Because of this, a popular “Hawk-watching Guanyinshan” event has been held here since 2003. Exhibition hold staff and volunteers have worked hard to promote local ecological tourism using birds of prey. We hope that through introducing raptors and their ecology, you can gain a better understanding of Guanyinshan and its environment, as well as a deeper appreciation for nature.

When people think of ferocious beasts, animals like lions and tigers usually come to mind. Yet, raptors are ferocious too, and include birds like eagles, falcons, hawks and owls. People may consider species like the Taiwan Blue Magpie or Black Drongo to be ferocious, since they are highly territorial and attack animals much larger than themselves to defend their territory. They are not raptors though.

The term “raptor,” or “bird of prey,” specifically refers to one of four major types of birds: eagles, falcons, vultures, and owls. They are carnivorous, catching prey and either tearing it into small pieces with their beak or swallowing it whole. There are about 50 species of raptor in Taiwan and the Raptor Research Group of Taiwan has recorded 31 of them at Guanyinshan. That's roughly 60% of all of Taiwan's raptor species.

Some raptors spend their entire lives in Taiwan, breeding and raising their youngcare. We call these “resident raptors”. They live in the same area all year round. Other raptors migrate seasonally for breeding and wintering, we call these “migratory raptors”.

Taiwan lies in the middle of the East Asian-Australasian Flyway. Because of its central location along this Flyway, many different species of migratory bird use Taiwan to refuel or rest on the way to their breeding or wintering grounds, with others overwintering or breeding here. For migratory birds with shorter migration routes, they may stay for as little as just one to two days. Yet, for those that will need to travel long distances to get to their next destination, Taiwan is truly an oasis. Here, they can rest, refuel and wait out bad weather. You can see many kinds of migratory raptors passing through Gaunyinshan in the spring. If you are lucky, you can also catch them resting or hunting for prey.

In the spring of 1991, the Taiwan Wild Bird Federation observed 180 Grey-faced Buzzards crossing the main peak of Guanyinshan. This was the first record of such a large group of migratory raptors passing through Northern Taiwan. It picked the group's interest in learning more about the Raptors there. So, in the spring of the following year, the organization launched a 4-month raptor survey at Guanyinshan, involving groups such as the Wild Bird Society of Taipei, the Tamkang University Wild Bird Club and National Taiwan University's nature conservation Society.

In the spring of 1993, the Tamkang University Wild Bird Club took over the project, with students and raptor enthusiasts heading to the mountains in their spare time to do the surveys. The four species recorded most were the Crested Serpent Eagle, the Crested Goshawk, the Grey-faced Buzzard and the Chinese Sparrowhawk. They're now collectively known as the four Graces of Guanyinshan. The Crested Serpent Eagle is the largest and most easily recognizable of the group. Meanwhile, during the breeding season, Crested Goshawks can be seen in groups of two or three, soaring in the air before doing aerial displays of pressing their wings down and doing a quick flapping motion.

The migratory Grey-faced Buzzard is quite relaxed. During their Northern migration, they can often be seen resting in the treetops or eating. The migratory Chinese Sparrowhawk is the smallest of the four. Yet in groups, they put on quite an aviation show, sometimes being neat and uniformed, while other times changing formation quickly.

Both the Crested Serpent Eagle and the Crested Goshawk are known to breed in Guanyinshan and are resident raptors.The Crested Serpent Eagle is famous for its ability to catch snakes, so it's also known as the “Snake Eagle”. Its wingspan is 160 centimeters, making it one of Taiwan's larger raptors. Both adults and immature birds have bare yellow facial skin, something no other raptor in Taiwan has. Adults also sport a clear white horizontal band on both the edge of the wings and the tail feathers which is very easy to identify. In addition, the Crested Serpent Eagle vocalizes very often and many times is spotted only after being heard. It is a good starter species for getting into raptor identification.

The Crested Goshawk is relatively smaller with a wingspan of just 80 centimeters. It’s only about half the size of the Crested Serpent Eagle. In flight, their wings look short and round, and they sport fluffy white feathers at the base of the tail, which are easy to spot. During the breeding season, they have a unique behavior of pressing their wings down and fluttering them very quickly while in flight. It is a behavior that quickly identifies the bird as a Crested Goshawk.

The Grey-faced Buzzard and the Chinese Sparrowhawk are migratory raptors, meaning

they will migrate North in the spring and South in the fall. Both species will pass through Taiwan during their migration, and most will not stay in Taiwan very long. The Grey-faced Buzzard is the most famous of Taiwan's migratory raptors, and has many local names, including the National Day Bird, the Mountain Back Bird, and the Southern Roadhog.

They are roughly the size of a Crested Goshawk, but with narrower and longer wings that have straighter trailing edges, a mouse gray face, a distinctive white eyebrow line and a beautiful brick red back.

The Chinese Sparrowhawk is small with a wingspan of just 60 centimeters. Defining features on adults include an orange chest and black wing tips. Though not as famous as the Grey-faced Buzzard, they create the largest migratory raptor flocks in Taiwan, with the current record set at over 270,000 in the fall of 2020. When they are flying high in the sky, they look like little specks, yet their feathers reflect the sunlight, making them twinkle like stars. To see a group of these birds flying in the same direction is to watch a river of motion beautiful to behold.

Guanyinshan’s rich forest ecosystem is home to many different animal species including the Oriental Rat Snake, Chinese Green Snake, Taiwan Japalure, Okinawa Tree Lizard and common Chinese Tree Frog.

The Crested Serpent Eagle, in addition to praying on snakes, also preys on lizards, crabs, snails and earthworms. Due to this very diet, during periods when there are fewer snakes or in difficult winters, they have a safe food supply. Outside of Guanyinshan, there have been cases of Crested Serpent Eagles eating earthworms or rhinoceros beetles contaminated with pesticides, leading to accidental poisoning and hospitalization.

When an ecosystem is healthy, raptors are too. The different raptors at Guanyinshan all have different diets. For instance, while the Crested Serpent Eagle mainly eats snakes and lizards, the Crested Goshawk feeds mostly on birds and squirrels. Meanwhile, for Oriental Honey Buzzards eat hornets and bees or bee pupae for dinner. This reduced competition for food among the different species is one of the major reasons why Guanyinshan can accommodate so many kinds of raptors.

The Crested Serpent Eagle begins preparing for the breeding season in February. Males will catch snakes or frogs and present them to females to court them. Females will make a special call announcing, if she has not been presented with such gifts yet. Once paired, they will build the nest together. Sometimes, on densely entwined vines that are invisible to the naked eye from the forest floor.

This large raptor only breeds once per year and lays one egg per nest. When the chick hatches, they are covered in white fluff. But as they get older, brown feathers gradually grow in. During the rearing period, the female stays with the eaglet and is responsible for feeding and protecting it, as well as maintaining the nest. Meanwhile, the male is responsible for catching and providing food for the two, as well as protecting the nest.

Young eagles will fledge after about two and a half months. By this time, it's almost the same size as an adult. It will remain near the nest as it practices haunting. And the parents will continue to provide food at this time. Once it is ready, it will leave to find a territory of its own.

Wing shapes for raptors vary, and each has its own pros and cons. For species with wide and long wings like the Crested Serpent Eagle, they can ride the air currents with ease and don’t need to flap their wings much. However, the disadvantage of wide wings is that flapping requires more energy. They are also more easily affected by the weather. When the weather is good and the updraft is strong, they can easily fly high and far; but when it is wet and cold or when air conditions are poor, they can’t fly as much. Species with slender wings such as the Chinese Sparrowhawk and the Grey-faced Buzzard have an easier time flapping and are not as easily affected by changes in the weather; however, if they are flying over water and the weather gets bad, they need to get closer to the shore.

Some raptors have unique flying techniques, such as the kiting behavior of the black shoulder kite. They can stop flying at a fixed point in the air and hover by beating their wings quickly. They use this method to search for prey on the ground. Another special flight technique is “display flight”. This is used to attract the mate or announced territory. An example of this is the raised wing flight of the Oriental Honey Buzzard.

The best time for raptor watching at Guanyinshan is from 9:00 a.m. to 12:00 p.m. During March and April, the weather is a bit unpredictable, with the mountaintop often shrouded in clouds. It is recommended you do your raptor watching from the mountainside during this time of year. Good locations include the Guanyinshan Visitor Center or the Linshao Hiking Trail.

In May, the weather is clear and the raptors are flying relatively high. During this time, it's better to wrap up your watch from the top of the mountain. Some good locations for this, include the Chuhuo hao viewing platform on the Niugangling Trail, as well as the

Jianshan Trail and the arch of Yinghanling.

In Autumn, migratory raptors are heading South. Yinghanling is a good spot for raptor watching at this time. The Jianshan Trail is 1,620 meters long and takes you to the top of

Jianshan. From there, you have a fantastic view of the Danshui river, Mount

Datun, and the Guandu plain. In May, there's even a chance you might see circling Oriental Honey Buzzards.

The Yinghanling trail, also known as the Tough Guy Peak Trail, is 1,563 meters. It starts next to Lingyun Temple and the walk is quite scenic. The Guanyinshan Visitor Center has a large square in front of it, as well as a parking lot and bus stop. You may not expect it but this is a good spot for raptor watching as well. In fact, every year the “Hawk Watching Guanyinshan” event is held there.

Raptor bodies have many special attributes which help them with flying and hunting.

Their bones are hollow but strong, allowing them to stay in the air and withstand the stresses of flight. Their sternum also extends into a keel, providing a larger muscle attachment surface and stronger pectoral muscles. The Peregrine Falcon, known for its explosive power and speed, has extremely well-developed pectoral muscles. Meanwhile, compared with other birds, raptors’ eye sockets occupy a considerable portion of the head, which is one of the reasons why their eyesight is so good. Another important feature of raptors is their sharp, hooked beaks. The outer beak is made of keratin, like claws and nails.

Lastly, raptors’ wings make them very strong flyers. The wing feathers can be divided into flight feathers and culverts. The flight feathers are long and hard, and the culverts are short and soft. The longer the outer flight feathers are, the more asymmetrical the vanes to the left and right of the rachis or feather shaft become. They will also have notches in these feathers which are used to help make flight more stable. Raptors have 12 to 14 tail feathers. These are used to control direction, aid the wings and act as a balance when perching, walking and jumping.

The Raptor Research Group of Taiwan with the support of the Forestry Bureau, Council of Agriculture Executive UN, conducted satellite tracking research on the migration of Grey-faced Buzzards from 2008 to 2011. During this period, they successfully tagged and released 13 individuals, Cape No.1 to Cape No.13. The researchers attached light-weight satellite transmitters to their backs, then they used the Argos Satellite System to get information on the birds' locations. All this was done, with the goal of unraveling the secrets of their migration routes.

Of the 13, the longest transmission signal lasted for 748 days. Six individuals provided locations for their wintering sites, which were in Busan, Mindanao and Palawan in the  Philippines. Meanwhile, four individuals successfully returned to their breeding grounds, which were located in various countries, including China, North Korea and Japan. From this work, it was discovered that during the fall migration, the birds stayed closer to the coast of China; while in the spring, they traveled further inland in China. Also, though the average weight of one of these birds was only around 440g, they traveled roughly 9,000 km annually on their migration route, including flying 900 km across the South China Sea.

To learn about raptors and their biology including information about their lifespan, behavior and activity range, individuals must first be identified. There are a few different methods for doing this, the first is through the use of leg bands. There are two kinds: the first is the color band, which has a distinct color and number on it that observers can easily identify from a distance; however the materials may not be very strong and sometimes can be removed by birds or fall apart due to exposure to the elements. Then, there are metal bands, though not colorful, these are made of a harder material and include a unique identification number which serves as a form of ID. It will also have the contact information of the banding unit so you can contact them if you come across the bird.

Meanwhile, for raptors with wide, long wings that spend much of their time soaring in the air, wing markers are a good option as well. Also, to better understand movement patterns, transmitters are a good tool. If a bird has a transmitter then researchers can use satellite or base station signals to figure out its coordinates and analyze the location of its movements. If the transmitter is able to stay on the bird for a long time, researchers can get an even deeper understanding of its flight path and migration patterns.

Though they may rule the skies, raptor species still face many threats on the ground.

Taiwan is small and densely populated, so it is inevitable that human-raptor interactions will take place. Yet, human activity often impacts the birds. For instance, roads fragment raptor habitat, creating situations where bird-vehicle collisions can take place. Cars traveling at high speeds can accidentally hit raptors, like Collared Scops Owls, or Crested Goshawks as they fly across. Meanwhile, at certain campgrounds, the trees bordering these areas may be removed, reducing forest habitat. Roads to these areas may also get expanded to allow for more guests, removing habitat for the insects, rodents and birds which raptors hunt.

Raptors face many human-made threats, such as car or window collisions, poisoning and poaching. These issues may seem small, but for birds that breed only once a year and only raise a few young at a time, they have a big impact.

You don't need a lot of equipment to go raptor watching. The most important thing is to have a good pair of binoculars, which help you to see the birds even if they're far away or up in the trees. They also make it easier to see feathers, enjoy raptor behavior and identify the species. Raptor watching takes you out into wide open spaces which are exposed to the sun. It's important to remember to use sunscreen and wear things like hats, sunglasses, bandanas, or arm sleeves, which help protect you from the sun's ultraviolet rays.

Raptors are at the top of the food chain and often serve as a barometer for ecological health. An area with raptors usually means that there are all kinds of other interesting plants and animals around, so keep your eyes open for them.

We must work together to protect raptors in their habitats. Ensuring their survival for the next generation.