But it can! ST seek out shallower waters for spawning purposes and then, in theory, lower flow would on avg perhaps provide more spawning habitat. This is a tough call, however, because spawning ST seek out upwellings as part of their required spawning habitat and perhaps it could be that there are fewer or less forceful upwellings under lower flow conditions.
PFBC surveys targeting YOY abundance in late spring or early summer in ST and BT streams suggested that lower flows during spawning the previous fall were better for ST year class production and higher flows during spawning were better for BT year class production. The surveys did not consider early spring max flow impacts, however. It’s clear from yrs of survey work that in Pa weak ST and BT year classes 1) are very frequently followed by strong year classes and 2) probably lead to better survival and growth within the year class that follows due to reduced competition. Nature has various ways of maintaining population balances and they are often readily witnessed in fish populations by fisheries biologists and ecologists.
I wholly agree with Mike. Trout need upflow from beneath the bottom up through the benthic stones of the right size.
Explaining my take:
When I was a teen a close-relationship neighbor (surrogate uncle) bred and hatched and raised trout.
(Unfortunately the rainbows that were popular for hatcheries at the time were from migratory breed. Really pretty with more red on their sides, but would only hold for a week or so, pool by pool disappearing to downstream. They needed a small pond to provide club members some fish.)
I wrote this previously, but the key was the water boiling up in the spring house where he would suspend the fertile eggs in baskets until they hatched and he could let them into the discharge, stone-built trough screened off according to size.
The point is that what Mike said about needing the water to flow up from the bottom, up through the bottom of the redd is critical.
It keeps the eggs from being smothered by silt.
It provides fresh water and oxygen and more constant water temperature.
And protection.
Such characteristics of natural, erosive water flow creates such situations.
A normally flowing stream (without repeated flooding), erosively carries and deposits the proper sized stones for the physics of the section of flow to push water from underneath.
The water that emerges to provide suitable habitat for a redd normally comes from the tail of the "pool" directly upstream. Other sources, perhaps sub-benthic spring flow from a deeper source than upstream drainage, also would seem to provide proper habitat.
It's seepage that reemerges.
It repeats and repeats.
Every flow of water with a normal benthic construct can be completely expected to create such upflow areas.
IMO that flow not only provides healthy water for trout redds, but serves many other forms of benthic life, which of course evolved from the physics of the stream and geology.
Also IMO, the use of the Whitlock-Vibert box failed a lot (especially at first) because they weren't placed in the stream bottom where water emerges from the benthos. The eggs in the WV box were silted and smothered.
(Vince and Charlie Fox tried to build redds in the Letort. I don't remember exactly and I haven't read his book for a long time. But they didn't apply the essential characteristic of a redd with upflow. They focused on size of stone they put in the benthos.)
Being able to identify likely places where physics would seem to provide the best upflows for redds can help locate them.
But as far as fishing during deer season, recommend don't do it for wild trout.
One year during the mid-1970s the first day of "buck" season at a camp near the bottom of the Pine Creek Gorge the air temperature was in the 70s. Masses of invasive Chinese (?) ladybugs drifted heavily through the air.
Decided to fish Slate Run.
Then after seeing a female brown, skinny and with white scratches and a group of smaller males at her sides and behind, I stopped altogether. Never again.
But stockies?
Eat them.
They weren't bred to act naturally. At all. They were bred to grow big and fast in a raceway, constantly exercising in swimming pods and eating lots of fulfilling food pellets with lots of ground noise.
They were bred for food. To grow fast and fat.
They were bred to not be afraid of a fisherman walking too heavily and closely along the bank or instream.
Wild trout don't tolerate any of that.
