分類 / Names
共通名の | 類義語 | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Environment: milieu / climate zone / depth range / distribution range
; 新鮮な水; 汽水性の 底生の; pH range: 7.0 - 7.5; dH range: ? - 20; potamodromous (Ref. 57765); 深さの範囲 0 - 200 m (Ref. 57765), usually 1 - 8 m (Ref. 57765). Temperate; 1°C - 19°C (Ref. 57765); 74°N - 46°N, 64°E - 162°E
Asia: Siberia, rivers Ob, Irtysh, Yenisei, Lena, Kolyma, Khatanga, Pyasina, Anabar, Olenyok, Yana and Lake Baikal (Ref. 57765). Non-migratory populations exist in all river systems (Ref. 57765).
Length at first maturity / サイズ / 重さ / 年齢
Maturity: Lm 86.9, range 65 - 167 cm
Max length : 200 cm TL オス/雌雄の選別がない; (Ref. 40476); 最大公表体重: 210.0 kg (Ref. 59043); 最大記録サイズ: 63 年 (Ref. 57765)
Extended snouts; four barbels in front of the mouth (Ref. 4639). The back is light grey to dark brown colored. The belly color varies from white to clear yellow. Five row s of scutes: 10-19D, 32-59L, 7-16V. Small star-like scutes between the main ones. Clearly slit inferior lip (Ref. 40476).
Found in deep and shallow parts of rivers, with moderate to swift current usually at depths of 1 to 8 m (Ref. 57765). Adults live essentially in freshwater although some fish frequently occur in estuaries. Males are sexually mature between 9 and 29 years; females between 9 and 34 years (Ref. 57765). Spawn in main river channel over stone-gravel or gravel-sand bottom and with strong current (Ref. 59043).
Life cycle and mating behavior
成熟 | 繁殖 | 放精 | 卵 | 生産力 | 幼生
Potamodromous species (Ref. 57765). In a natural environment, males reach sexual maturity at 9-1 5 years of age and females at 16-20 years (in water recirculation systems, sexual maturity can first occur at 5 years). Spawning happens in the summer and generally every two years. Membranes on eggs become increasingly more sticky after fertilization and this allows them to stick to the substratum. This can become a problem in nurseries, but it is solved by washing the eggs in clay or diatomaceous earth suspensions. Caviar (not fecundated ovocites ) can be over 1 0% of the corporal weight of a mature female. Incubation
lasts about 1 6 days (at 10-1 5°). Larval development lasts about 20 days (at 18°). Egg size 3.0-3.6 mm, larval length at hatching 10-12 mm.
Baillie, J. and B. Groombridge (eds.), 1996. 1996 IUCN red list of threatened animals. IUCN, Gland, Switzerland. 378 p. (Ref. 12255)
IUCNのレッドリストの状況は (Ref. 123251)
絶滅危惧 (EN) (A2bcd+4bcd); Date assessed: 24 October 2009
水産業: 高い商業の; 水産養殖: 商業; 水族館・水槽: 公共の水族館
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00263 (0.00154 - 0.00450), b=3.27 (3.13 - 3.41), in cm total length, based on LWR estimates for this species & Genus-body shape (Ref. 93245
栄養段階 (Ref. 69278
): 3.3 ±0.2 se; based on diet studies.
回復力 (Ref. 120179
): 非常に低い, １４年以上の倍増期間の最小個体群 (tm=7-34; tmax=63; Fec=16,500-420,000; K=0.03).
弱み (Ref. 59153
): Very high vulnerability (85 of 100) .