Fisheries are damaging and seemingly incompatible with the conservation of marine ecosystems. Yet fish are an important source of food and support the lives of many people in coastal communities. This paper considers an idea that a moderate intensity of fishing, appropriately scaled across species, could help in maintaining biodiversity, rather than reducing it. The scaling comes from an intuition that rates of fishing mortality of species should be kept in line with production rates of the species, a notion known as balanced harvesting. This places species conservation and exploitation on an equal footing in a single equation, showing quantitatively the relative levels of fishing mortality that species of different abundance can support. Using a dynamic model of a marine ecosystem, we give numerical evidence showing for the first time that fishing, if scaled in this way, can protect rarer species, while allowing some exploitation of species with greater production. This works because fishing mortality rates, when scaled by production, are density-dependent. Such fishing, operating adaptively to follow species' production rates over time, contains a feedback that would help to protect species from overfishing in the presence of uncertainty about how marine ecosystems work.

中文翻译：

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通过平衡捕捞捕捞生物多样性

渔业具有破坏性，而且似乎与海洋生态系统的保护不相容。然而，鱼类是重要的食物来源，支撑着沿海社区许多人的生活。本文考虑了一个想法，即适度的捕鱼强度，适当地跨物种缩放，可以帮助维持生物多样性，而不是减少它。这种比例来自于一种直觉，即物种的捕捞死亡率应与物种的生产率保持一致，这一概念被称为平衡捕捞。这将物种保护和开发置于一个等式中，从数量上显示了不同丰度的物种可以支持的捕捞死亡率的相对水平。使用海洋生态系统的动态模型，我们提供的数字证据首次表明，如果以这种方式扩大捕捞规模，可以保护稀有物种，同时允许对产量更高的物种进行一些开发。这是可行的，因为捕鱼死亡率在按产量衡量时取决于密度。随着时间的推移，这种捕鱼会自适应地跟踪物种的生产率，其中包含一种反馈，有助于在海洋生态系统如何运作存在不确定性的情况下保护物种免遭过度捕捞。