In the summer and autumn, the Chinese sturgeon, living in the shallow waters outside the mouth of the Yangtze River, traveled back to the Yangtze River. After more than 3,000 kilometers of upstream bombings, it returned to the Jinsha River to spawn and breed. After the birth, the juveniles grow up to about 15 cm and carry them to the sea. They were born in the upper reaches of the river for generations and grew up in the sea.
The Chinese sturgeon is living in the Dajiang and offshore, and is a bottom fish that is migratory or semi-migric. In the spring and summer, from May to June, the group is clustered in the estuary, and in the autumn it goes up to the upper reaches of the river. In ancient times, “the rivers, the Huaihe River, the Yellow River, and the deep waters of the Liaohai Sea” were used.
In the "Compendium of Materia Medica", the record of its diet is: "They also eat, open mouth and mouth, listen to their own, eat and not drink, crab fish are eaten by mistake." In fact, Chinese sturgeon is inhaled by the expansion of the oral membrane. Most of the food objects are small animals that live in mud or trapped in mud. During the entire migration and detention period from the ocean into the river, the Chinese sturgeon basically does not feed. Therefore, the energy consumption of Chinese sturgeon in fresh water and the nutrients required for gonadal development depend on the large amount of fat accumulated in the body before entering fresh water. Thus, in fresh water, the closer to a mature individual, the thinner the body becomes.
In summer and autumn, Chinese sturgeons living in shallow waters outside the mouth of the Yangtze river swim back to the Yangtze river. After more than 3,000 kilometers of bo-stroke upstream, they return to the jinsha river to spawn and breed. After the baby fish grow up to about 15 cm, and carry them to live in the sea. So they were born in the upper reaches of rivers and grew in the sea for generations.
Chinese sturgeon lives in the river and offshore, is the bottom fish, with migratory or semi-migratory. Spring and summer may - June to cluster in the estuary, autumn up to the upper reaches of the river. Ancient: "Zhan river, huai, the Yellow River, the three deep water", "the house is in the pile of stones between turbulence".
In compendium of materia medica, it is recorded that: "it eats, opens its mouth, listens to itself, eats but does not drink, the crab fish all eats by mistake". In fact, the sturgeon inhales food by the expansion and contraction of the oral membrane, and most of the food objects are small animals living on the mud surface or trapped in the mud residue. Sturgeon from the sea into the entire migration of rivers and detention period, basically do not feed. Accordingly, the energy that Chinese sturgeon consumes in freshwater and the nutrition that gonad development needs, rely on it to be in before entering fresh water body accumulates a lot of adipose wait for a material. Thus, in fresh water, the nearer an individual is to maturity, the thinner his body becomes.
夏秋两季,生活在长江口外浅海域的中华鲟回游到长江,历经3000多公里的溯流博击,才回到金沙江一带产卵繁殖。产后待幼鱼长大到15 厘米左右,又携带它们旅居外海。它们就这样世世代代在江河上游出生,在大海里生长。
中华鲟生活于大江和近海中,是底层鱼类,具有洄游性或半洄游性。春夏季5-6月间喜群集于河口,秋季上溯而至江河之上游。古有:“鳣出江、淮、黄河、辽海深水处”,“其居也在堆石湍流之间”。
《本草纲目》中对其食性的记载为:“其食也,张口接物,听其自入,食而不饮,蟹鱼都误食之”。实际上中华鲟是靠口膜的伸缩将食物吸入,食物对象多数是生活于泥表或陷藏在泥渣中的各类小型动物。中华鲟从海洋进入江河的整个洄游和滞留期间,基本上不摄食。因此,中华鲟在淡水中的能量消耗和性腺发育所需的营养,依靠它在进入淡水前体内积累的大量脂肪等物质。因而,在淡水中,愈接近成熟的个体,身体就愈消瘦。
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