Turned with their bellies up, the fish’s head is placed into a small receiver and a bar code marker is injected into the fish. This marker resembles an extremely small sliver about a couple mm long and the width of a human hair.
Again the fish travels though the PVC plumbing and into this holding tank where they will sit until release back into the river. The whole process from capture to release takes about 48 to 72 hours. Crews can process about 30,000 fish a day.
At the end of the day the fish are released through hose and pipe down to the river.
The purpose for this marking is scientific. Considered to be one of two remaining “wild” Chinook stocks, WDFW wants to track the migration habits by way of reports from commercial fishers who scan a sampling of their catch. As some of have seen, a portion of the head is removed, frozen and sent to the lab where it is further dissected to find and identify the bar code marker.
(continued in part 3)