Using the information on this chart: The location of the counting tower for the Gulkana salmon runs is located ABOVE the area that is the sport fishery. This is approximately 9 miles upstream of the Sourdough boat launch. Therefore these counts reflect the numbers of fish that have already passed through the sport fishing zone.

Based on radio-tracking data, these king salmon take an average of five days to travel the 45 miles from the Richardson Highway Bridge to the counting tower upstream of Sourdough. From the Sourdough fishing area these kings will take only about one day to reach the counting tower upstream. A trend showing increasing numbers could mean there are good numbers of fish passing through the Sourdough area, but it could not give much information on what is going on in the lower river unless this trend is during the early half of the run timing. Once several years of counts have been compiled, a fairly accurate representation of the run's characteristics will become available which would reflect the timing of a typical year run. By offsetting the average daily counts by 5 days, an angler will be able to determine what an average run would be like in the lower river. Of course each year can vary widely so this method will only be for ballpark assessments unless fishing the Sourdough area where counts would be closer to representing the sport fishing in that area.