Birds Of Japan 58:Oriental Reed Warbler 日本の野鳥 58:オオヨシキ

Oriental Reed Warbler オオヨシキリ Scientific name: Acrocephalus orientalis The Oriental Reed Warbler is a large, energetic warbler best known for its loud

Oriental Reed Warbler オオヨシキリ Scientific name: Acrocephalus orientalis

The Oriental Reed Warbler is a large, energetic warbler best known for its loud and powerful song. In Japanese it is called オオヨシキリ / Ōyoshikiri. It has plain brown upperparts, pale underparts, a strong pale eyebrow stripe, and a long pointed bill.

In Japan, the Oriental Reed Warbler is mainly a summer visitor. It arrives in spring and breeds in dense reed beds, marshes, riversides, lakeshores, and wetlands. The male often sings from the top of a reed stem, delivering its famous loud, harsh song across the wetland.

Its Japanese song is often remembered as 「ギョギョシ、ギョギョシ」, making オオヨシキリ one of the most recognizable voices of Japan’s summer wetlands.

Habitat: Reed beds, marshes, riversides, lakeshores, wet grasslands, lowland wetlands

Range in Japan: Widespread summer visitor in suitable wetland habitats across much of Japan
Diet: Insects, spiders, caterpillars, and other small invertebrates
Season: Spring to autumn in Japan; migrates south for winter
Size: About 18–19 cm
Nesting: Deep cup-shaped nest woven between upright reed stems
Behavior: Male sings loudly from exposed reeds to defend territory and attract a mate
Conservation: Depends strongly on healthy reed beds and protected wetland habitats

The Oriental Reed Warbler is one of the loudest voices of Japan’s summer wetlands. Hidden among tall reeds, the オオヨシキリ fills marshes and riversides with its powerful, harsh 「ギョギョシ、ギョギョシ」 song. It arrives in spring to breed in dense reed beds, where males sing continuously from the highest stems. Although its brown plumage is simple, its voice makes this energetic summer visitor impossible to ignore.

Oriental Reed Warbler オオヨシキリ

The Oriental Reed Warbler is a familiar summer visitor to Japan's wetlands, riversides, lakes, ponds, and extensive reed beds. This medium-sized warbler is mostly brown above and pale below, with a strong bill and a distinctive pale eyebrow. Although it can be difficult to see among the dense reeds, its loud and energetic song makes its presence unmistakable.

During the breeding season, males often sing from the top of a reed stem, defending their territory with the famous harsh calls of “gyo-gyo-shii, gyo-gyo-shii.” It feeds mainly on insects and other small invertebrates and builds its nest low among reeds and other wetland vegetation. In autumn, it migrates south to spend the winter in Southeast Asia.

IUCN Status

Least Concern

Habitat

Reed Beds, Marshes, Riversides, Lakes, Ponds, Wetlands

Region

Japan and East Asia in Summer, Southeast Asia in Winter

Behavior

Loud Singing, Reed-top Perching, Insect Hunting, Summer Migration

Population

Widespread and Common in Suitable Reed-bed Habitat

オオヨシキリ Oriental Reed Warbler

オオヨシキリは、夏になると日本へ渡ってくる代表的な夏鳥で、湿地、河川、湖、池、そして広いヨシ原などに生息しています。体の上面は褐色で、下面は淡い色をしており、太いくちばしとはっきりした淡い眉斑が特徴です。ヨシの茂みの中では姿を見つけにくいですが、大きく力強いさえずりによって存在をすぐに知ることができます。

繁殖期になると、オスはヨシの先端にとまり、縄張りを守るために「ギョギョシ、ギョギョシ」と聞こえる大きな声で盛んにさえずります。主に昆虫や小さな無脊椎動物を食べ、ヨシや湿地の植物の間に巣を作ります。秋になると日本を離れ、東南アジアなどの越冬地へ渡っていきます。