It is still too early to know how a recent high-water event marked by upwards of two feet of snow melting under several inches of rain in December will impact ecosystems – especially considering how low water tables were in late summer and throughout the fall months. Thus we lost not just fish less than six inches in length in the stream, but also the next-year class that was present as fertilized eggs in the stream.” “The difference was likely due to the timing as the 2016 flood occurred in mid October when brook trout had already spawned. “We only found three brook trout in 2017 in the 100-meter stretch we sampled when we would normally find between 100 to 125,” Niles said. In 2016, the upper third of the Loyalsock Creek experienced a flooding event that came later in the season. That leaves the following summer's population as the surviving 'old guard' and a whole bunch of babies. ” Then in the spring and early summer, the young-of-year would face less predation from bigger brook trout and less competition from the one-year-olds who might overlap in their prey. Post-flood in the fall, the remaining large fish had more available locations to spawn free of competition – so they could take up the best areas with the highest survival of their eggs. The fish that survived then spawned in October and those “surviving adult fish and the newly emerged young-of-young the spring afterward flourished because they had less competition and predation,” said Wilson. However, this doesn’t tell the entire story of the stream as while they saw increases in young-of-year populations there were decreases in adult populations, likely due to mortality of fish that were six inches or less during the flood. The next year, overall brook trout numbers and young-of-the-year populations skyrocketed. The flooding events of 2011 came earlier in the calendar year, before the typical late-fall brook trout spawning season. We were looking at pre-population estimates and post-population estimates for events like Hurricane Irene and Tropical Storm Lee,” said Niles. “We have been looking at 30 sites along headwater streams of the Loyalsock Creek and recording brook trout populations since the summer of 2011.
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