Even the most complex models used in fishery management are cartoons of reality.

Even the most complex models used in fishery management are cartoons of reality. They reduce hundreds of links in food webs to a handful and inadequately represent processes operating over space. Many of their assumptions are as flawed today as those of the simplest models of the past. Fish stocks, for one. are still assumed to be populations of a species that are isolated from one another. Yet many populations mix at their edges and some even migrate through areas occupied by other populations. Furthermore, the more complex models suffer from a "crisis of complexity"—more is really less. Adding layers of detail, each carrying its own set of assumptions, produces instability. The model's behavior becomes erratic, and conclusions drawn from it can be downright misleading.

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