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Half of all fish people eat worldwide now come from fish farms. So farms need to do more to keep up with demand.

现在全世界一半供人类食用的鱼来自养鱼场。因此，养鱼场需要采取更多办法以满足需求。

“If we look to the future, at today’s per capita fish intake¹ around the world we would need to double aquaculture production.”

“如果我们展望未来，按照如今世界各地人均鱼的摄入量，我们将需要采用双水产养殖生产模式。

Ron Hardy² is the University of Idaho’s Director of Aquaculture Research. He presented his research at the recent International Symposium³ on Fish Nutrition and Feeding in Sun Valley, Idaho, which he also chaired.

爱达荷州大学水产养殖研究中心的主任，Ron Hardy ，最近，在爱达荷州太阳谷召开的营养与喂养国际研讨会上，提出了他自己的研究，这场国际研讨会由他主持。

In the wild, rainbow trout⁴ eat insects and other, smaller fish. But Hardy says there aren’t enough little fish to feed larger fish in the wild and still meet market demand as the human population increases. So he’s used selective breeding to create strains of farmed fish that get by on food that’s less expensive than little fish—feed made from soybeans, corn and wheat.

在野外，虹鳟鱼以一些昆虫及其他较小的鱼为食。但是Hardy表示，野外并没有足够的小鱼去喂养大鱼，并且随着人口的增加还需要满足市场需求。因此，他通过采用选择性育种方式来培育养殖渔业的新品种，由大豆、玉米、小麦等食物制成的鱼饲料，其成本比喂食小鱼更低。

Some of the farmed fish really thrive: 16 years ago, Hardy had to wait a year for a one-pound trout. These days, his efforts yield trout up to four times as large in the same amount of time.

一些人工养殖鱼类蓬勃发展：16年前，为养出一条重达一磅的鳟鱼，Hardy不得不等待一年。而如今，在他的努力下，在相同的时间里鳟鱼的产量高达四倍多。

“So, it would be kind of like if you were going to breed dogs. So we’ve got everything from Rottweilers to little Scotties or whatever.”

“因此，这就像是如果你要喂养狗，我们可以从罗特韦尔犬、小斯科蒂犬或者其他犬种那学到你所需要的。”

But the farmed fish are not completely vegetarian⁵.

但是养殖鱼类也并不是完全食素。

“Soybeans don’t have skeletons, they don’t have bones and the bones in fish meal are a major source of minerals for the fish, for example.”

“例如，大豆没有骨架，它们没有骨头但是对于鱼类而言，鱼粉中的骨头是矿物质的主要来源。”

And much like humans, fish diets require omega-3 fatty acids, not found in terrestrial plants. So Hardy has to add a little fish-oil back into the plant-based feed. For those of us without waders, this kind of aquaculture is our best shot at a fish fry.

并且与大部分人类一样，鱼的饮食中需要欧米珈- 3脂肪酸，在陆生植物中不含这种元素。因此，Hardy不得不在植物性饲料里加入一点鱼油。对于我们这种没有高筒防水胶靴的人们而言，这种类型的水产养殖是我们养殖鱼苗最好方法。