I fish the Ugashik River in the Bristol Bay district of Western, Alaska. Alaska is the only state with fisheries sustainability written into the state constitution. There are no other countries or states that can make a claim like that. So there is a broad culture of fisheries sustainability in Alaska as a whole. Additionally, many fisheries in Alaska are MSC (Marine Stewardship Council) certified, including Bristol Bay, where I fish. MSC is the most trusted independent fisheries sustainability certifier in the world. The Monterey Bay Aquarium also has a fisheries sustainability certifying program called Seafood Watch--they also certify my fishery.
Within the state there are many different fisheries, all fished and managed in a different way. I have been commercial fishing since I was 15 years old. I was always a crewman but when I bought my own limited entry permit (allow me to fish), I decided to buy in Bristol Bay since I believe it is the most sustainable fishery in Alaska, making it likely the most sustainable fishery in the world. We have the largest sockeye salmon run on earth (65 million sockeye last year) and our fish are totally wild--no hatcheries or augmentation of any kind. Our fishery was established to make fishing quite hard and to distribute the resource between as many families as possible. My fishery is almost all family fisheries consisting of a single family fishing during the summer. No one is getting rich but we are all making some kind of living harvesting a small but of the bounty. In the Russian far east they have a very different approach to harvesting their salmon. They see the millions of salmon they have there as a resource that needs to be taken out of the water as quickly as possible. So a few very large state run corporations scoop up the fish in the most efficient way possible. This precludes both sustainability and family fisheries.
Alaska Fish and Game has detailed statistics on habitat both at sea (where salmon spend most of their lives) and in the small creeks where they spawn. They study ocean temps and nutrients as well as predation and fishing pressure in international waters. During the summer when the salmon come back to their natal streams to spawn then die, they know exactly how many fish are caught every day (fish buyers report what they have bought), how many fish swam up river (every river has a fish counter--literally a person camping on the upper river all summer counting fish) and they do flyovers to estimate fish by the size of the schools they see. They limit the catch by the area we can fish (GPS points delineating a geographic fishing area), by boat size (32 foot max for drift boats), by net length (50 fathoms for us setnetters), mesh size (5 1/4" max), net position and other subtle rules, and, most importantly, by the days and times we can fish. These are called "openings." The biologist for our river (every river has its own dedicated biologist) takes into account all the info above (catch, escapement, etc) and decides when and for how long to allow us to fish. He makes these decisions in real time based on the numbers he is getting from myriad sources. These opening announcements are made over the radio each day and are for the following day. For example, "Fishing will be allowed for 12 hours tomorrow from 12 midnight to 12 noon, a 12 hour opening."