Daily Limit of Kokanee Reduced at Tyee Lake, BC
After a conversation with a biologist, here’s the information on the decision for a reduced daily limit on Tyee Lake in Region 5.
Personally, I believe we need to support this decision to ensure the future of our kokanee fisheries in British Columbia. What are your thoughts after reading this?
As of January 2022, the daily limit of kokanee will be reduced from 10 kokanee per day to 5 kokanee per day at Tyee Lake, BC in Region 5. This lake holds a feral population of self-sustaining kokanee which were historically stocked from Meadow Creek eggs. While this change may come as a shock to some anglers who have come to love this lake and it’s generous daily limit, the change comes out of necessity to meet the needs of current and new kokanee fisheries across the province.
To fully understand the decision made for a daily limit reduction, we need to consider the history, science and stocking potential that Tyee Lake has for the provincial kokanee stocking program. We also need to consider that the kokanee fishery in British Columbia is closely monitored every year. Daily limits, stocking efforts and regulations changes can be made in a timely manner to ensure a future fishery for generations to come.
The need for a change in regulations in Tyee is due to low kokanee numbers in the Kootenays (Meadow Creek on Kootenay Lake and Hill Creek on Arrow Lake). Historically, these two spawning channels provided the source for all kokanee stocking in British Columbia. Now both systems are in conservation so are not able to provide kokanee eggs for stocking. The reason why these two systems went into conservation status is from a predator explosion that happened about ten years ago in Kootenay Lake. This predator explosion took a run of kokanee that ranged from 250,000 to 1,000,000 down to a population of 12,000 to 15,000 some years. After this decline of kokanee brood stock for the province happened, biologists starting using kokanee brood stock from an enhanced spawning channel at Hill Creek in the Arrow Lakes. This system had a surplus of kokanee brood stock that helped the kokanee hatchery program through the next four to six years after the Kootenay collapse. While the province gets kokanee from a few other sources, these sources are not nearly the size of Hill or Meadow Creek that can provide all our needs. After this decline, other lakes were being looked at to potentially take brood out of.
Other lakes were tried as brood lakes, like those in the interlakes area. Deka, Bridge and Sulphurous Lake kokanee were tried as brood stock. Biologists believed the kokanee eggs from these lakes grew so fast that the egg quality was poor, so they could not use the eggs as brood candidates for the province. They believe the eggs that grew fast developed a thin eggshell and they would get a fungus infection. This would cause many eggs to die in the hatchery. Even though the larger Bridge Lake kokanee have more eggs than the Tyee kokanee (less brood would be needed), the egg mortality proved to not be a viable source.
About three years ago, Tyee lake kokanee eggs were tried experimentally. The Freshwater Fisheries Society of BC took in the low tens of thousands of eggs just to try them in the hatchery to see if they had the same survival issues. It was discovered that Tyee lake kokanee survive very well in the Clearwater Hatchery unlike Bridge, Deka and Sulphurous. In the second year of testing, Hill Creek brood stock was declining, so the Society went in more seriously to Tyee and repeated the first experiment and were highly successful in rearing kokanee at Clearwater. Biologists hypothesize that Tyee kokanee grow slower, spawn at two or three years so their eggs are more resilient in being broken and getting fungus when they are brought to the hatchery. Last year, there was no more brood stock from Hill or Meadow Creek. The Society went in to Tyee aggressively to get brood stock.
Some of the brood stock eggs from Tyee go to Meadow Creek and are planted in the gravel to try and recover Meadow Creek, because Tyee kokanee were originally genetically sourced from Meadow Creek. The eggs from Tyee Lake are now going to be relied on to stock other lakes in the region and the province if the other original sources do not start producing. This new source for the province needs to be secured to help stock all kokanee lakes in British Columbia.
The daily limit reduction is a balance of risk in reducing some opportunity on Tyee but making sure we have enough fish to stock the lakes that we currently do, because we have had short falls some years with egg supply. There have been years where there was not enough eggs to stock some kokanee lakes like, Bridge, Sulphurous and Purden. A shortage can cause huge hits to the recreational fishery in the area being stocked. There has been a shortage every five to eight years and because of this decisions are made as to what lakes do not get stocked.
While the daily limit might have been reduced at Tyee Lake, biologists are hoping to see larger kokanee sizes in the lake over the years. This increase in size should translate into the same retention poundage compared to the current fish sizes.
Last year, the Society took 1,893 females and 757 males from Tyee that produced 1.4 million eggs for the province. The Provincial recreation need for the province is 2.8 million eggs annually. Kootenay lake requested 1 million eggs for recovery this year. Kootenay Lake has requested upwards of 4 million eggs in a given year (most from Hill Creek on Arrow Lake). If there is a continued shortfall or collapse the province would require several million eggs from Tyee in the short-term future. While Tyee lake could never meet the full request of 7 million eggs, biologists will do their best to accommodate the provincial recreational request (2.8 million) than any surplus for Kootenay Lake recovery. These requirements and requests are the reason for the precautionary rationale for the reduced limits at Tyee.
The kokanee eggs taken from Tyee Lake last year will have an effect on the population of kokanee in Tyee. Biologists are monitoring kokanee populations closely. In general, kokanee sizes should increase over time due to eggs being taken from the system. Biologists do not want to collapse the Tyee Lake kokanee population due to removing too many females.
What does the future of Tyee Lake look like? The goal of the current program being put in place is twofold. First, the kokanee of Tyee will help ensure future kokanee fisheries in the province. Second, the goal of Tyee Lake kokanee is to see larger fish which will continue to attract anglers to the lake. A back up placeholder of 20,000 kokanee has been put in place in case over harvest is done by collecting eggs for the hatchery. Removal of eggs seems to be low risk, but we do not know what removal of this number of spawners will do. How do biologists know if over harvest of kokanee stocks in Tyee has happened? The general indicator of a reduced population is a quick increase in size. This tells us that densities are going down substantially.
Kokanee brood stock are not only important for the current lakes stocked with kokanee. The objective for kokanee stocking in British Columbia is to continue to expand kokanee into other lakes in the province and provide opportunities for people. The stocking program will continue to move forward and not focus on one lake, but all the lakes. The top priority for biologists is to secure brood stock. New and existing lakes cannot be stocked if the fish are not available.
If anglers decide to stop fishing Tyee due to the new reduced daily limit, will the fish in the lake continue to decline in size? Can kokanee size be related to not enough kokanee being removed from the lake? What other variables will affect Tyee Lake kokanee? All these questions are connected to how Tyee lake is managed now and how it was managed in the past. Originally, the main objective when stocking Tyee Lake was to have a lake that produced kokanee in the 1.5-2lb weight classes. In the beginning, the daily limit of the kokanee stocked in Tyee Lake used to be 5 kokanee per day. Eventually, biologists learned that these fish were way more successful in spawning then they thought. It was getting to the point where the lake was overstocked. The limit then went up to 10 kokanee per day to get the size of fish back to where they wanted it, into the 30cm objective range.
What does the future hold? There are too many variables to account for when determining what the future fish stocks will look like in the province. For example, if Meadow Creek and Hill Creek recover and there are brood sources again the limit might be raised to 10 again if the kokanee in Tyee remain successful at spawning and angler pressures stay low. This scenario has happened at least two other times in the history of Tyee Lake. Biologists are always monitoring the kokanee in Tyee Lake and respond to population fluctuations in the feral population. By monitoring kokanee sizes and densities, biologists can respond to the needs of the lake and either allow a higher harvest quota or a lower harvest quota based on the overall health of the lake.
***NOTE*** Please note that this article was written after a conversation with Mike Ramsay, Senior Fisheries Biologist. Some of the information has been quoted directly from our conversation and has been verified as true at the time of publishing this information.