In preparation for a talk I'm giving tomorrow night, I've been rereading the great book "The Fisherman's Problem," by Arthur McEvoy. It's a fabulous book, and if you like Doris Kearns Goodwin or Kevin Starr, I recommend tracking down a copy. It's actually the product of McEvoy's thesis research and it's an indispensable reference for anyone who works on fish in the west, or pretty much anywhere. Here's the passage that stopped me today, from a section about goldminers turning to salmon fishing when the gold dried up:

"A fish, however, is more than a gold nugget. It is part of a species - a coherent, self-perpetuating entity that works...Unfortunately for this particular species, its genetic program included instructions for collecting that accumulated food into a form, a salmon run, which happened to be convenient for the human economy to tap for it's own purposes." p.72

That's really the trick about catching, selling, and buying wild fish. They're not just gold nuggets you can pick up and sell, but complicated living creatures that depend on a web of environmental factors to survive. Even if you never caught a one, you couldn't guarantee that you'ld see the same number of fish in a river every year. Which can make it hard to plan a business.