Local Trout Streams – Still Flowing High

Lush Green Growth¬† –¬† Lots Of Water

The local small creeks are still flowing very high for this time of the season! The water table and ground springs are in great shape with lots of water from all of the rain that we have received this spring and summer. The flood of June 21st and a few high flow events since that time have already cleaned the stream beds and scoured the pools, so when the water levels drop a bit and the flow clears up enough, you will see the difference that a few good flushes can do for a trout stream.

It has been a few years since the last good flush on Bighill Creek, West Nose Creek and other area streams. The added willow growth from our “Bow Valley Riparian Recovery and Enhancement Program” will help constrict the flow and scour a deep narrow channel, with cobble and gravel exposed in some areas.

This will be great for any new resident trout, migrating in from the Bow River, or those new trout that have hatched on Bighill Creek early this year. A cleaner creek means more invertebrates or food and some pretty good new habitat for trout to live in. Deeper pools, undercuts and runs, will all be enhanced by the flood waters that tore thru the creek a few times in June and July.

You can see from the photo to the left that some of our first willow plantings are now growing out and over the stream channel. This added new fish habitat will more than double the holding capasity of Bighill Creek’s resident trout population. Some may start out small, but over time they will grow into larger trout and improve the health of the sport fishery and boost the amount of wildlife that depend on trout for survival. Herons, mink, diving/fish eating/ waterfowl and other wildlife will have a more productive habitat for foraging.

I have fished the Bow River here in Cochrane a few times this year already, and the number of juvenile brown trout is up again this year. I suspect that many of these small brown trout will be returning to the Bighill Creek later on this season. This should help boost the population of brown trout in the creek. Also, we did have a successful hatch of Millennium Creek brook trout again this year. This along with new hatchlings from further upstream, should enhance the brook trout population in the stream as well.

This is the largest brown trout that I have captured in the Bow River so far this year, but a lot of smaller brown trout were present in the river. These are all very nice and healthy juvenille brown trout and the numbers of them that move into the creek will definitely boost the fisheries trout restoration program in Bighill Creek. There will be plenty of new habitat ready for the small brown trout, when they migrate up the Bighill Creek.

Every year, I conduct an angling survey to see how the rainbow trout hatch in the previous year was, on the Jumpingpound Creek. Using a fly rod and a variety of very small trout flies, I can usually catch the smaller trout that are present in the Bow River, in the Town of Cochrane. Unfortunately, this season, as of July 23rd, there were no rainbow trout captured by this angling method. However, it may happen yet, so I will continue with my survey.

The numbers of rainbow trout in this reach of the Bow River has been dramatically reduced in recent years. Collapsed fishery, is a better discription for the state of the rainbow trout fishery on the middle Bow River. It is hard to pinpoint the exact reason for this, because I don’t spend all of my own time studying the river’s fishery, but I suspect a number of variables are involved in this terrible state of our rainbow trout populations. I have heard that the Bow River in Calgary and downstream is also experiencing a reduced rainbow trout population, but the river is still maintaining a good sport fishery for now.

All we can do on our end, is improve the fish habitat on small tributaries to the Bow River and increase spawning habitat, in the hopes that our sport fishery will rebound some day. There just seems to be so much happening these days, with envasive species entering the river system and human development encroaching on key areas that our trout depend on for reproduction. A good example is Ranch House Spring Creek. This small spring creek is used by brook trout as a nursery habitat and also, more importantly, as a spawning habitat. A few years ago, a storm drain outflow was constructed on the Ranch House Creek drainage. Since that time, huge volumes of ground water run-off have been entering the small spring creek and quickly eroding the natural existing stream channel into a washout.

The numbers of spawning trout have dwindeled, from a high of 32 brook trout redds in 2016, down to 3 last fall. I am positive that the changing stream channel geometry and substrate is the cause for the decline in reproductive numbers. The pumping of spring groundwater further upstream is also a major concern these days. We cannot afford to loose any spring water from such an important spawning tributary as Ranch House Creek.

 

 


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