Blakiston's fish owl facts for kids
Quick facts for kids Blakiston's fish owl |
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Ketupa
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blakistoni
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The Blakiston's fish owl (Ketupa blakistoni) is the largest living owl in the world. It is a special type of fish owl. These owls are part of the eagle-owl group. They are experts at hunting in areas near rivers and lakes. You can find them in China, Japan, and the Russian Far East.
This owl belongs to the family of typical owls, called Strigidae. This family includes most owl species. Blakiston's fish owl and three other owls that eat fish are grouped in the genus Ketupa. Their home is usually a forest near water. They need big, old trees for their nests. These areas must have lakes, rivers, or springs that do not freeze in winter. Henry Seebohm named this bird after Thomas Blakiston. Blakiston was an English naturalist who found the first owl specimen in Japan in 1883.
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Understanding the Blakiston's Fish Owl
How Scientists Classify This Owl
The Blakiston's fish owl was first described in 1884. This was done by an English bird expert, Henry Seebohm. He found a specimen near Hakodate in Japan. He first put it in the genus Bubo. He named it Bubo blakistoni to honor Thomas Blakiston.
It is sometimes called the Blakiston's eagle-owl. This is because it might be more closely related to the Eurasian eagle-owl. This idea comes from studies of its bones and DNA. Some experts think all fish owls should be in the Bubo genus. This shows that the owl's family tree is a bit complicated!
Recent genetic tests in Russia suggest this owl is indeed closer to other fish owls. This means it might be different enough from typical Bubo owls.
What Does This Giant Owl Look Like?
The Blakiston's fish owl is the biggest living owl species. Males usually weigh between 2.95 and 3.6 kilograms (6.5 to 7.9 pounds). Females are larger, weighing up to 4.6 kilograms (10.1 pounds). Their total length is about 60 to 72 centimeters (24 to 28 inches).
Even though the great gray owl is sometimes longer, the Blakiston's fish owl is heavier. The Eurasian eagle-owl is also a very large owl. However, the Blakiston's fish owl often has a greater average weight and wingspan. Its wingspan can reach 178 to 190 centimeters (5 feet 10 inches to 6 feet 3 inches). Some very large ones might even reach 200 centimeters (6 feet 7 inches)!
This owl looks a bit like an eagle-owl. But it is more brown or tan in color. Like other fish owls, it has broad, shaggy ear tufts. These tufts hang slightly to the side. Its upper body is buff-brown with dark streaks. The underside is lighter. Its throat is white, and its eyes are yellow.
Unlike most eagle-owls, the Blakiston's fish owl has completely feathered legs. Its wing beats are silent, which helps it hunt. Its large talons look like those of a great horned owl.
How Does It Sound?
The calls of these owls can be different depending on where they live. In Japan, the male calls twice, and the female answers with one note. On the mainland, they have a more complex four-note duet. It sounds like HOO-hoo, HOBO-hoooo. In Russia, their calls sound like SHOO-boo and FOO-foo-foo.
Their voices are deep, but not as loud as the Eurasian eagle-owl's. They call most often just before they start nesting. This usually happens around February. When a pair calls together, their duet is so well-timed that it sounds like one bird! Young owls make a loud, slurred shriek, like phee-phee-phee.
Different Types of Blakiston's Fish Owls
Scientists recognize two main types, or subspecies, of this owl:
- K. b. blakistoni (Seebohm, 1884): These owls live in Hokkaido, northern Japan, and the Kuriles. They have tawny-brown faces with black stripes. Their wings are deep brown with many buff yellow bars. Their tails are dark brown with cream-yellow bars.
- K. b. doerriesi (Seebohm, 1884): These owls are found in eastern Siberia down to the Vladivostok area and near the Korean border. They are larger than the Japanese owls. They have a large white patch on top of their heads.
These two groups of owls have been separated for at least half a million years.
Where Blakiston's Fish Owls Live
Blakiston's fish owls live in thick, old forests near water. This includes areas along rivers or wooded coastlines. They need very large, hollow tree cavities for their nests. They are one of the biggest birds to use tree hollows anywhere.
These owls need parts of rivers that stay unfrozen in winter. In very cold northern winters, open water is only found where the current is fast. Or, where warm spring water comes up. Even a few meters of open water can help them survive the winter.
What Blakiston's Fish Owls Eat and How They Behave
Blakiston's fish owls eat many kinds of water animals. Their main food is fish, like pike, catfish, trout, and salmon. Some fish they catch can be very large, even two or three times their own weight! They might hold onto a tree root to pull a big fish onto the bank.
In spring, they also eat many frogs. Crayfish and other crustaceans are also part of their diet. Males might prefer frogs and smaller fish, while females hunt larger fish. Fish are more important to their diet than for almost any other owl species.
They also eat mammals, especially in winter. Smaller mammals include martens and rodents. They can even catch large mammals like hares, rabbits, foxes, cats, and small dogs. They sometimes eat birds too, like hazel grouse and waterfowl.
These owls hunt in two main ways. They either wade in shallow river water or sit on the river bank. They wait for movement in the water. They might wait for hours until they spot prey. Once they see something, they drop into the water or fly a short distance to catch it. They also eat dead animals, like meat used in traps. Small prey is eaten right away. Larger prey, like big fish, are dragged onto the bank before being eaten.
These owls are most active at dusk and dawn. During the time they are raising their young, you might see them hunting during the day. They spend a lot of time on the ground, which is unusual for an owl. Sometimes, they even make a regular path along riverbanks while hunting.
Raising Young Owls
Blakiston's fish owls do not breed every year. This depends on how much food is available. They start looking for mates in January or February. Eggs are laid as early as mid-March, even when there is still snow.
They like to nest in hollow tree cavities. These are usually in old forests with both evergreen and deciduous trees. The nests are typically high up, at least 12 meters (39 feet) off the ground. The nest cavities must be very large to fit these big birds.
They usually lay one or two eggs. In Russia, it is often just one egg. The eggs are about 6.2 centimeters (2.4 inches) long. The male owl brings food to the female while she sits on the eggs. He also feeds the young owls. The eggs hatch in about 35 days. The young owls leave the nest in 35 to 40 days. But their parents continue to feed them for several more months.
Young owls stay with their parents for up to two years. Then they leave to find their own territory. Blakiston's fish owls can start forming pairs at two years old. They are ready to have their own young by age three. Because young owls stay with their parents for so long, you might sometimes see a family group together.
Once they are fully grown, these owls have few natural enemies. However, they hunt on the ground, so they might be more at risk from animals like Eurasian lynx or Asian black bear. There have been a few rare reports of these animals attacking adult owls in Russia.
Protecting the Blakiston's Fish Owl
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The Blakiston's fish owl is an Endangered Species. This means it is at high risk of disappearing forever. Its numbers are dropping because its forest homes are being destroyed. Rivers are being developed, and dams are being built.
In Japan, there are only about 100 to 150 of these birds left. On mainland Asia, there are more, perhaps up to a few thousand. Globally, there are an estimated 1,000 to 1,500 individuals. This is about 500 to 850 pairs.
In Russia, fish owls can be killed by fur-trappers. They also sometimes drown in nets set for salmon. Hunters might shoot them. In Japan, they are sometimes hit by cars or killed by power lines. Some owls have also been exposed to lead, possibly from eating animals shot with lead bullets. With such a small population, every death is a big problem.
People are working to help these owls. In Japan, they are educating people. They are also putting up large nest-boxes and providing extra food. Scientists say that finding Blakiston's fish owls means a forest and its fish populations are healthy.
There is also concern about the owls' genetic diversity. This means there isn't much variety in their genes. This can make them less healthy. In Hokkaido, Japan, the owl population is slowly recovering. But they still need more suitable places to live.
Important to Local Cultures
The Blakiston's fish owl is very special to the Ainu of Hokkaido, Japan. They see it as a divine being called Kotan koru Kamuy. This means "God that Protects the Village."
In Russia, the Evens people sometimes eat the species. In the past, the Udege people in Primorye also hunted fish owls for food. They valued their high fat content. They also used their wings and tails as fans to keep insects away while hunting. This practice is not common anymore.
