19-The Northern Goshawk オオタカ（大鷹）

Birds Of Japan 19:The Northern Goshawk (Accipiter gentilis)日本の野鳥19:オオタカ（大鷹）

The northern goshawk (Accipiter gentilis) is a large and powerful bird of prey belonging to the Accipitridae family. It is known for its impressive hunting skills and widespread distribution across the Northern Hemisphere. Here are some key points about the northern goshawk:

Appearance: The northern goshawk exhibits sexual dimorphism, with females being larger than males. Adult males typically have a length of 46-56 cm (18-22 inches) and a wingspan of 94-105 cm (37-41 inches). Females are larger, measuring 56-65 cm (22-26 inches) in length with a wingspan of 108-127 cm (43-50 inches). Both sexes have short, broad wings and a long tail, which aids in their agility during flight and hunting.
Range and Habitat: Northern goshawks are found across a wide range, including North America, Europe, Asia, and parts of northern Africa. They prefer forested areas, especially mature and dense coniferous or mixed woodlands, where they can find suitable nesting sites and an abundance of prey.
Diet: The goshawk is an opportunistic predator with a varied diet. Its primary prey consists of medium-sized birds such as pigeons, grouse, jays, and crows. However, they are also known to hunt mammals, including squirrels, rabbits, and other small mammals. Their hunting technique involves using stealth and surprise to capture their prey.
Behavior: Goshawks are powerful and agile fliers, capable of navigating through dense forests with ease. They are known for their intense hunting strategies, often using a "still-hunting" technique, where they perch quietly and wait for prey to come into view before launching a surprise attack. They are also skilled at flying low to the ground to surprise their quarry.
Breeding: Northern goshawks are monogamous and territorial during the breeding season. They build large nests made of sticks and twigs high up in trees. The female lays a clutch of 2-4 eggs, which she incubates for about 30-40 days. The male assists in providing food for the female during this period. The young chicks fledge and leave the nest after about 5-6 weeks but may remain dependent on their parents for several more weeks.
Conservation status: The conservation status of the northern goshawk is generally considered to be of "Least Concern" by the International Union for Conservation of Nature (IUCN). However, local populations may face threats from habitat loss due to deforestation or human disturbance.
Legal protection: In many regions, the northern goshawk is protected under various wildlife and bird protection laws, making it illegal to hunt, capture, or harm these birds.

Overall, the northern goshawk is a fascinating raptor known for its hunting prowess and its role in maintaining the balance of ecosystems in the regions it inhabits.

オオタカ（学名: Accipiter gentilis）は、大型で力強い猛禽類であり、ハリアネズミ目に属します。その印象的な狩猟能力と北半球全域で広く分布していることで知られています。以下は、オオタカに関する主なポイントです：

外見：オオタカは性的二形を示し、メスがオスよりも大きいです。成体のオスは通常、46-56 cm（18-22インチ）の長さと94-105 cm（37-41インチ）の翼幅を持ちます。メスはより大きく、長さ56-65 cm（22-26インチ）、翼幅108-127 cm（43-50インチ）です。両性とも短くて広い翼と長い尾を持っており、飛行と狩猟の際の俊敏性を助けます。
分布と生息地：オオタカは北アメリカ、ヨーロッパ、アジア、および北アフリカの一部など、広範な地域に生息しています。成熟した密生した針葉樹や混合林などの森林地帯を好み、適切な巣の場所と豊富な獲物を見つけることができます。
食性：オオタカは機会を捉える捕食者であり、多様な食事を摂ります。主な獲物はハト、キジ、カケス、カラスなどの中型の鳥類です。しかし、リス、ウサギ、その他の小型哺乳類なども狩ることが知られています。彼らの狩猟技術は、獲物を驚かせるために静かに待ち伏せる「静止狩り」と呼ばれる技法を用いることが一般的です。また、獲物を驚かすために地面近くを低空飛行するのにも長けています。
行動：オオタカは力強く、俊敏な飛行ができ、密生した森林を軽々と飛び回ります。彼らは強烈な狩猟戦略で知られており、しばしば「静止狩り」と呼ばれる技法を使って、静かに止まって獲物が視界に入るのを待ち、奇襲を仕掛けます。
繁殖：オオタカは繁殖期には一夫一婦であり、縄張り意識が強いです。彼らは枝や木の枯れ葉などを使って大きな巣を高い木の上に作ります。メスは2-4個の卵を産み、孵化には約30-40日かかります。この期間中、オスはメスにエサを提供するのを助けます。ヒナは約5-6週間で巣立ちし、その後数週間は親の世話を受けることがあります。
保護状況：オオタカは、国際自然保護連合（IUCN）によって一般的に「軽度懸念（Least Concern）」とされています。ただし、生息地の喪失や人間の干渉によって地域ごとに個別の個体群が脅威にさらされることがあります。
法的保護：多くの地域で、オオタカは野生生物や鳥類保護法などの法律で保護されており、これらの鳥を狩猟したり、捕獲したり、傷つけたりすることが違法です。