The most recent survey of one or two summers ago revealed a substantial change from the previous survey of possibly 20 yrs or so earlier. Even while there was a good population of BT in Section 01 for decades and in the very upper end of Section 02 by the quarry, it did not extend downstream, although there might have been a few stragglers at times farther down. Section 03, the DH section, was not known for its wild trout, although you could find a few (very few) wild ST from near-by tribs, which as you probably know, at least one of which is Class A. Section 03 suffered from habitat and temperature problems when I first placed it in the DH program in the mid-1980’s. As recently as somewhere around the 2008-2010 period during the stocked trout residency survey of Bear Ck just above the DH Area very few wild BT, if any were found.(And temp problems still exist downstream).
You may have made a good point though because as I was answering the question the wild BT pop in the headwaters slipped my mind, so through “exploratory” movements and development of more suitable temps in the DH Area wild BT may have gradually started to reproduce in that stretch (03). Stocked BT would have found the same conditions, however, and would have been directly stocked in that stretch so the successful spawning of stocked fish could not be ruled out. The overall point of my response, however, despite the possible misfire on Bear Ck, is that there has been ample evidence of successful spawning by PFBC BT over the years, including fall stocked fish in otherwise warmwater fish populated streams, such as the East Branch Perkiomen, and the Codorus Ck case is clear cut, as it was a warmwater stream with dam blockages when Lake Marburg was constructed.
Of note regarding Bear Ck is that Section 02 was one that we worked with for 2-3 yrs during the stocked trout residency study. It originally received stockings of ST and BT for decades, in part because of pH concerns for RT during the preseason snow melt (at times) period. Buffering capacity was not great there. Policy was simple…no RT to be stocked in streams with pH lower than 6.5. We later learned that while sensitive to pH, PFBC RT were tolerating slightly lower pH’s by a few tenths, so when stocked trout residency (BT and ST) turned out to be only moderate at best and maybe even poor for ST, I started experimenting with RT and measured their residency, which was much better in Bear. Thus, the species mix was changed for Section 02 and Section 03. You will note, however, that one of those sections received BT inseason this year. That was most likely because of the RT shortage in portions of the hatchery system this year. Additionally, trout residency is less of a concern inseason because the fish are fished over immediately.
Finally, the expansion of the BT population in Bear Ck may have been assisted by the shift to solely RT stocking, as this has allowed BT populations to expand in some other waters. You probably read previously that I started it with Tom Greene’s (Coldwater Unit Leader) approval within the PFBC years ago and was shifting to purely RT stockings when I felt that it had a good chance of pushing a Class B BT section pop to Class A, which would then allow me to remove the section from the stocking program, providing a source of stocked trout for other waters within the statewide system. It worked on two York Co stream sections and appeared to have worked on a third that had been less closely monitored, so saying it absolutely worked would have been a bit generous.
