As for the cessation of adult trout stocking resulting in the appearance of wild browns, wild browns were present (in very low numbers) for at least a couple of decades. Their probable gradual increase may have been related to the reduction in adult stocking (way too many fish were being stocked) that occurred over a decade ago and/or the habitat work, including the riparian vegetation enhancement, that occurred just prior to that time. This has been discussed here before.
It is improbable that the wild brown trout population rose from some substantially depressed level and reached the biomass equivalent of Class A within a year and a quarter once adult stocking ended after the spring stocking of 2012. Adding to the improbability is that large numbers of nearly adult size RT fingerlings (7.25 inches) were stocked in fall, 2012, amounting to many, many more than the number of adult trout that the PFBC had been stocking in the stream and creating a competitive force of their own.
Additionally, the drivers of the Class A equivalent biomass found in summer, 2013 were wild browns that had been exposed to adult stockings. The only ones that had not been exposed to adult hatchery trout stockings were from the fish spawned in fall, 2012. At the time of the summer, 2013 survey the fish produced from the fall, 2012 spawning activities were only 2-3 inches long, amounting to a minor component of the biomass. Ultimately, this appears to be another wild brown trout population that reached the equivalent of Class A status, at least for one summer, in spite of a stocking program.
