Red-crowned crane 丹頂鶴

• published: 04 Dec 2015
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The red-crowned crane (Grus japonensis), also called the Japanese crane (Chinese: 丹顶鹤 or 丹頂鶴; Hanyu Pinyin: Dāndǐng Hè; Japanese: 丹頂鶴 or タンチョウヅル, tanchōzuru; Korean: 두루미, Durumi; the Chinese character '丹' means 'red', '頂/顶' means 'crown' and '鶴/鹤' means 'crane'), is a large east Asian crane and among the rarest cranes in the world. In some parts of its range, it is known as a symbol of luck, longevity and fidelity. Adult red-crowned cranes are named for a patch of red bare skin on the crown, which becomes brighter in the mating season. Overall, they are snow white in color with black on the wing secondaries, which can appear almost like a black tail when the birds are standing, but the real tail feathers are actually white. Males are black on the cheeks, throat and neck, while females are pearly gray in these spots. The bill is olive green to greenish horn, the legs are slaty to grayish black, and the iris is dark brown. This species is among the largest cranes, typically measuring about 150 to 158 cm (4 ft 11 in to 5 ft 2 in) tall and 120–150 cm (3 ft 11 in–4 ft 11 in) in length (from bill to tail tip). Across the large wingspan, the red-crowned crane measures 220–250 cm (7 ft 3 in–8 ft 2 in).[2][3][4][5] Typical body weight can range from 7 to 10.5 kg (15 to 23 lb), with males being slightly larger and heavier than females and weight ranging higher just prior to migration.[6][7][8] On average, it is the heaviest crane species, although both the sarus and wattled crane can grow taller and exceed this species in linear measurements.[7][9][10] The maximum known weight of the red-crowned crane is 15 kg (33 lb).[11][12] Among standard measurements, the wing chord measures 56–67 cm (22–26 in), the exposed culmen measures 13.5–16.7 cm (5.3–6.6 in) and the tarsus measures 25.5–30.1 cm (10.0–11.9 in). In the spring and summer, the migratory populations of the red-crowned crane breed in Siberia (eastern Russia), northeastern China and occasionally in northeastern Mongolia[1] (i.e., Mongol Daguur Strictly Protected Area). The breeding range centers in Lake Khanka, on the border of China and Russia. Normally the crane lays 2 eggs, with only one surviving. Later, in the fall, they migrate in flocks to Korea and east-central China to spend the winter.[1] Vagrants have also been recorded in Taiwan.[1] In addition to the migratory populations, a resident population is found in eastern Hokkaidō in Japan.[1] This species nests in wetlands and rivers. In the wintering range, their habitat is comprised mainly by paddy fields, grassy tidal flats, and mudflats. In the flats, the birds feed on aquatic invertebrates and, in cold, snowy conditions, the birds switch to mainly living on rice gleanings from the paddy fields. https://en.wikipedia.org/wiki/Red-crowned_crane 丹頂鶴（學名：Grus japonensis），也叫仙鶴、白鶴（其實白鶴是另一種鶴屬鳥類）、鴜鷜、日本鶴，中國古籍文獻中對丹頂鶴有許多稱謂，如《爾雅翼》中稱其為仙禽，《本草綱目》中稱其為胎禽。丹頂鶴是鶴類中的一種，因頭頂有紅肉冠而得名。它是東亞地區所特有的鳥種，因體態優雅、顏色分明，在這一地區的文化中具有吉祥、忠貞、長壽的寓意。丹頂鶴身長約120公分至150公分，翅膀打開約200公分，丹頂鶴具備鶴類的特徵，即三長——嘴長、頸長、腿長。成鳥除頸部和飛羽後端為黑色外，全身潔白，頭頂皮膚裸露，呈鮮紅色。其次級飛羽和三級飛羽形長彎曲成弓狀，兩翼摺疊時，覆於整個短尾上面，被人誤認為是尾羽。 傳說中的劇毒鶴頂紅（也有稱鶴頂血）正是此處，但純屬謠傳，鶴血是沒有毒的，古人所說的「鶴頂紅」其實是砒霜，即不純的三氧化二砷，鶴頂紅是古時候對砒霜隱晦的說法。[1][2]丹頂鶴的尾脂腺被粉䎃。幼鳥體羽棕黃，喙黃色。亞成體羽色黯淡，2歲後頭頂裸區紅色越發鮮艷。丹頂鶴繁殖地在中國黑龍江的三江平原和嫩江中下游地區、俄羅斯的遠東和日本等地。它在中國東南沿海各地及長江下游、朝鮮海灣、日本等地越冬。歷史上丹頂鶴的分布區比現在要大得多，越冬地更為往南，可至中國福建、海南島、台灣等地。由於這種鳥在文化中的特殊地位，地方志書中一直有著詳細的記載，為研究它的古代分布提供了詳實的資料。 https://zh.wikipedia.org/wiki/%E4%B8%B9%E9%A1%B6%E9%B9%A4