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Millennium Creek Spawning Channel Construction-2010

Millennium Creek Spawning and Egg Hatch

††† It has been ten years since the Millennium Creek Spawning Channel was constructed. This fall will mark the 10th successful brook trout spawning season in the channel. I donít know how many thousands of newly hatched generations of trout have resulted from spawning on the channel, but it is significant.

††† The spawning channel was constructed by partners Inter Pipeline and Bow Valley Habitat Development, of Cochrane. It was completed in August of 2010. That same fall, the first spawning occurred on the channel, only weeks after it was completed. The tenth successful hatch should be occurring in the New Year, and I look forward to that, this winter.

††† The construction of the spawning channel involved a lengthy permitting process, but by the spring of 2010, all permits and permissions were in place. Log retaining walls were pre-fabricated off site, and then the logs were moved to the site and installed at the base of the feeder spring.

††† This source of clean, clear spring ground water makes the spawning channel a very reliable fall spawning habitat for brook trout. Every year there has been a successful trout hatch. During the winterís cold months, the warmer spring water flows incubate the eggs.

 

†† The hatch of brook trout eggs can start in late November and into December, with emergence starting as early as the first week of January. After the hatch, the brook trout will stay in the gravel, living off of the egg sack, until the tiny trout come out of the gravel in the new year.

††† I sometimes refer to the spawning channel as our own little urban trout hatchery, but everything is completed thru the natural process, so all we have to do is monitor the results and conduct occasional maintenance.Because the ground spring water flow comes directly out of the ground, just above the channel, there are no other outside influences that could threaten the trout spawning or incubation.

††† Storm drains have impacted other small spawning tributaries, on the Bighill Creek, such as the storm drain on Ranch House Spring Creek, but that is often the case, if the importance of spawning trout is not respected enough by fisheries managers to put special protections in place to protect the habitat.

††† The Town of Cochrane has been very supportive over the years, which helps.

††† This will be the tenth spawning cycle for brook trout, on the spawning channel that we built. That first fall, just after the spawning channel was built, it was very rewarding to find brook trout spawning in their new habitat on Millennium Creek.

††† There was also spawning occurring on a few sites that we created on the creek further downstream of the channel, during the restoration program on Millennium Creek. The habitat enhancement project, which took four years to complete, was finished in 2008.

††† The restored creek is still functioning as a prime nursery habitat for juvenile trout and also more importantly, as a spawning tributary to the Bighill Creek trout fishery. Things are looking pretty good these days, on the creek.

††† Apart from seeing a few brown trout in the channel, over the years, there is not any evidence that they are spawning on the small spring feeder stream. However, this could change at any time, especially if we get good flows in our area spring creeks. This can happen after a wet summer, like the one we are having right now.

††† There are enough spawning brown trout on the main stem of the Bighill Creek to keep the populations growing, so this is not a big deal, to have just brook trout spawning in Millennium Creek.

††† It was probably around 2010or 2011 that I first noticed the young hatchling brook trout, in the winter months, on the spawning channel. Only a few years ago, I finally confirmed a hatch of brook trout on the lower creek.

††† So overall, the Millennium Creek has earned its title as one of the more important spring feeder creeks that enter the Bighill Creek. Ranch House Spring Creek has a storm drain that is causing excessive erosion problems of the once productive spawning habitat, so Millennium Creekís reputation as the most reliable spawning tributary is secure.

††† The hatch of trout eggs happens sometime in December or late November, but the emergence is consistently in the first few months of the New Year, January or February. Fortunately, there is plenty of small aquatic invertebrates for the newly hatched trout larva to feed on, when they first drift free of their spawning gravel beds. This is important for the young troutís early start in life, over the first few months..

Above: The log retainer walls for the spawning channel were constructed off site and then transported to the spring channel for installation.

Above: This photo shows how the channel looked, just after it was installed in the excavated spring channel. The log retainers kept the channelís loose gravel in place.

Above: This photo shows a section of the spawning channel, just after completion. All of the spawning gravel was screened and installed into the channel, right on site.

Above: This is what the spawning channel site looked like, before the excavation took place. There was plenty of good spawning gravel, but not adequate flow and depth. Much of the main volume of flow was subsurface. By excavating down and concentrating the flow into a narrow channel, the site would be transformed into a spawning channel.

Left: The completed spawning channel, shown a few years later, from the same downstream position. The branches covering the spawning habitat are to help conceal the spawning trout and provide some overhead cover. The gradient has been stepped down to create the right velocity of flow and depth for brook trout spawning.

††† The cost of the project was approximately $7,000.00, so we can safely say that that investment has been paid for many times over. A great way to maintain our wild brook trout populations in Bighill Creek.

††† Over time, the log retainers may bio-degrade, but the channel should stay intact for many years to come. I will be happy to report back to you in the next decade.

†††

Left: This beautiful Millennium Creek male brook trout is guarding a nest or redd. The trout has already fertilized some eggs that a female laid down and the trout is hanging around to fertilize more eggs, from another female, when she shows up. Male brook trout are like other trout, they will fertilize multiple femaleís eggs. The stronger and larger males get priority over the smaller more aggressive male trout.

††† You will often see larger males chasing other smaller males away, when a receptive female has excavated its egg nest in the gravel. The female fans the gravel to create a depression in the clean gravel, and then she will deposit the eggs, while the male immediately fertilizes the eggs as they are falling into the nest.

††† The male brook trout are much more colourful than the female. Also, the male jaws are slightly hooked, like a salmon.

Above: A large brook trout holds over the freshly disturbed spawning gravel, in the spawning channel, just after it was constructed. The spawning channel insures that there will be a higher than normal survival rate for eggs that are laid down and fertilized on Millennium Creek, every year.

Above:†† The newly hatched brook trout will drift downstream, soon after they have hatched. The tiny brook trout feed on real small aquatic invertebrates, after they have they have ingested all of the remains in their egg sacks. They will double in size, over the summer months.

Left: This small brook trout is only a few centimetres in length, so eating one of the small midge flies thatlie spent on the surface film, makes for a good sized meal. A good diet of midge larva, pupa and adults will enhance the growth of young trout and get them off to a good start in their aquatic lives.

††† The surface meals of midge are not as common as the tiny troutís hunt for submerged aquatic invertebrates. The protein rich diet of bugs will allow the trout to grow rapidly over the first months of free swimming.

††† If there are larger trout present, the small trout will stay concealed in cover and they will not show themselves as much as the trout that have juvenile trout habitat all to themselves. Danger is always present for young trout, including dragonfly nymphs, water beetles and some caddisfly larva.

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