Pacific Black Duck vs Brent Goose
Anas superciliosa 比較対象 Branta bernicla
Side-by-Side Comparison
| 属性 | Pacific Black Duck | Brent Goose |
|---|---|---|
| 学名 | Anas superciliosa | Branta bernicla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 50.2 cm (19.8 in) | 63.9 cm (25.2 in) |
| 体重 | 1000.5 g (35.29 oz) | 1335.0 g (47.09 oz) |
| 食性 | Dives for fish and aquatic invertebrates; serrated bill adapted for gripping prey; diet varies with … | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| 一腹卵数 | 3-15 | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Pacific Black Duck
Freshwater and brackish wetlands across Australasia and the Pacific Islands, from freshwater lakes and rivers to coastal estuaries, mangroves, and irrigated agricultural areas. Highly adaptable to human-modified landscapes.
Brent Goose
Breeds on high-Arctic tundra; winters on estuaries, coastal mudflats, saltmarshes, and sea-grass beds along Atlantic and Pacific coastlines. One of the most strictly coastal wintering geese.
Song & Call Comparison
Pacific Black Duck
Female gives a loud, emphatic quacking series; male utters a soft quip note. Common call is a loud, repeated quack; alarm is an insistent, rattling quacking burst.
Brent Goose
A low, guttural 'rronk' or 'ronk-ronk' from flocks. Soft nasal calls in feeding groups. A subtle, understated call for a goose — less loud than most Anser geese.
Geographic Range & Migration
Pacific Black Duck
Found across sub-Saharan Africa and Madagascar; locally sedentary in freshwater lakes and rivers year-round.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
保全状況
Pacific Black Duck
Brent Goose
How to Tell Them Apart
Pacific Black Duck
Brownish-black body with pale buff feather edges giving scaly appearance. Bold pale buff supercilium and dark eye-stripe and crown stripe on paler face. Iridescent green speculum. Gray bill; orange legs. …
Brent Goose
Small; mostly black head, neck, and breast. Small white neck-patch on adults. Back dark brownish-gray; belly pale gray to white depending on subspecies. White undertail coverts. Sexes similar.
About These Birds
Pacific Black Duck
パシフィックブラックダックはオーストラリア、ニュージーランド、太平洋島嶼部に広く分布するカモです。全身が褐色で、目の上に特徴的な白い眉斑があります。淡水の湿地、湖、川、河口に生息します。農業用水路にも適応しており、都市部の公園でも見られます。
Brent Goose
北極圏で繁殖し、北半球の海岸で越冬する小型のガン（体長55〜66cm）。黒い頭・首・胸に短い白い首輪が特徴。Branta bernicla（コクガン）は主にアマモなどの海草を食べ、干潟や浅い入り江を好む。日本でも北海道・東北の海岸で越冬する姿が見られ、個体数は比較的少ない。Anatidae科。