Inoue Masako, Shimura Ryoji, Uebayashi Akiko, Ikoma Shinobu, Iima Hiroko, Sumiyoshi Takashi, Teraoka Hiroki, Makita Kohei, Hiraga Takeo, Momose Kunikazu, Masatomi Hiroyuki
Kushiro Zoo, Kushiro, Hokkaido 085-0201, Japan.
J Vet Med Sci. 2013;75(8):1055-60. doi: 10.1292/jvms.13-0030. Epub 2013 Apr 15.
Red-crowned (or Japanese) cranes Grus japonensis are native to eastern Hokkaido, Japan--the island population, and mainland Asia--the continental population that migrates from breeding grounds along the Amur River Basin to winter in east China and the Korean Peninsula. The island population was reduced to about 50-60 birds in early part of the 20th century. Since 1950s, the population has increased to more than 1,300 as a consequence of human-provided food in winter, resulted in change of their habitats and food resource. From the carcasses of 284 wild cranes from the island population, collected in Hokkaido since 1976 until 2010, we measured six physical parameters (body weight and lengths of body, wing, tarsus, tail and exposed culmen) and divided into groups by sex and three developmental stages (juvenile, yearling and adult). All parameters of males were larger than those of females at the same stage. Total body length of females tends to grow up earlier than males, in contrast to body weight. Obvious time trends were not observed in these all parameters during 34 years for these six categories measured, except total length of male juveniles, which showed a significant increasing trend. These results provide the first extensive data on body size and mass in the wild red-crowned cranes.
丹顶鹤（或日本鹤）Grus japonensis原产于日本北海道东部的岛屿种群，以及亚洲大陆种群，该大陆种群从阿穆尔河流域的繁殖地迁徙至中国东部和朝鲜半岛越冬。20世纪初，该岛屿种群数量减少至约50 - 60只。自20世纪50年代以来，由于冬季人类提供食物，该种群数量已增至1300多只，这导致了它们栖息地和食物资源的变化。从1976年至2010年在北海道收集的284只岛屿种群野生鹤的尸体中，我们测量了六个身体参数（体重以及体长、翅长、跗跖长、尾长和喙长），并按性别和三个发育阶段（幼鸟、一岁鸟和成年鸟）进行分组。在同一阶段，雄性的所有参数均大于雌性。与体重相反，雌性的体长往往比雄性更早停止生长。在测量的这六个类别中，除雄性幼鸟的体长呈显著增加趋势外，在34年期间这些参数均未观察到明显的时间趋势。这些结果提供了野生丹顶鹤身体大小和质量的首批广泛数据。
