Something similar happened up at Naknek quite a few years ago. A guy from Astoria gill netted up there and supposedly caught a sturgeon in his net. Turned out that he had brought it up from Astoria! 
There are green sturgeon in Alaska. A few get caught every year on the Copper River delta. I caught one about 20 years ago and when I was cleaning it, found that it had two radio transmitters in glass tubes implanted in it's stomach. There was a tag on one of them with the name of Dr Pete Klimley ant the University of Cal Davis. He ran the Department of Biotelemetry where they studied the movements of fish and sharks and marine mammals. The sturgeon I had caught was part of a study of the movement of sturgeon in San Francisco Bay and the Sacramento River. He was pretty excited when I called him and told him it had been caught in the gulf of Alaska. That sturgeon had traveled over 1800 miles from where it was tagged. He turned me onto a web page that had color coded graphs that showed the movements of the different sturgeon on the bay and river. Of course when the sturgeon I caught left the bay, the radio equipment didn't have the range to track it to Alaska and they had no idea where it was. As an aside, I met a lady this summer who was one of Dr Klimley's students who took part in the sturgeon study.
