The Family Day Fishing Derby was cancelled earlier this week, as angler concern for the fishery on Kootenay Lake continues to grow.
Numbers of kokanee have plummeted from a high of an estimated 1.7 million return spawners to Meadow Creek and Lardeau River in 2011 to about 150,000 in September, adversely affecting the Gerrard rainbow and bull trout numbers to a degree that organizers had no recourse but to cancel the February fishing derby.
“This derby was intended to be a fun and exciting event and many of you can attest that spending two-and-a-half days on Kootenay Lake at minus-10 degrees without a bite or catching one- to two-pound rainbow is not fun or exciting,” the Family Day derby website, ctrcanadderby.com, stated. “In fact, one of the 2014 fall three-day derbies did not measure any fish and the prizes had to be randomly drawn.”
Robert Di Pietro, president of Canadian Training Resources who sponsor the derby, says they are cancelling the event due to an extreme decline in fish stocks in Kootenay Lake.
“The lake is practically empty of anglers and fish, a real blow to our economy,” said Di Pietro in an email. “The results from our 2014 survey estimate that close to half-a-million dollars was spent over a three-day period from our derby alone.”
The popular derby attracted about 650 anglers this year, and, with a top prize of $10,000 for longest Gerrard, it was an economic boon for the area.
Nevertheless, the Ministry of Forests, Land and Natural Resources’ fish biologist Matt Neufeld is not panicking, at least from a fisheries and conservation perspective.
“We recognize that kokanee numbers are down and we are seeing that with anglers, resulting in a whole bunch of pretty hungry Gerrard rainbows, and we’re starting to see a decline in those numbers, just because of it. It’s part of a natural cycle and our job now is try and reduce the time that it takes for that cycle to happen.”
Since the kokanee peak in 2011, stocks have declined steadily resulting in a return of about 450,000 in 2013 and 150,000 this year. Despite the dive in the kokanee count, the number of mature Gerrards spawning on the Lardeau River at Trout Lake in April-May was over 700, a good return for rainbows.
“They were down a bit, but they are still much higher than the long-term average (of about 300-400) . . . I’m anticipating we will see some decline there, we have over the last few years,” said Neufeld. “Based on what we’re hearing from anglers, catch-rates seem to be declining on the lake and that’s no huge surprise.”
Gerrards and bull trout are very effective predators and the past years’ high numbers of large trout is a significant reason for the kokanee decline. The Gerrard spawning count has seen an “unprecedented increase” in the last decade, with a high of 1,100 in 2012. Prior to 2011 the highest Gerrard count was about 600 with a low of 200 in 2001.
“There is no conservation concern for kokanee, they are not going to go extinct in Kootenay Lake. It’s certainly really low for providing enough food for Gerrard rainbows and bull trout on the lake. They are very effective predators; given the numbers we had in the lake, we think they are just eating themselves out of house and home.”
In the fall of 2013, fisheries biologists also discovered that kokanee were infected with the hematopoietic necrosis virus (IHN), which can increase the mortality rate of hatched fish or fry.
But studies by MFLNR fisheries biologists found that fry from the infected areas were free of IHN, and that Gerrards did not contract the virus.
“We tested Gerrard’s this spring and they were negative so they don’t have IHN and the data from the strain we have here . . . Rainbows are actually pretty resilient to this strain, so I don’t think IHN is a concern for Gerrards,” said Neufeld.
The fisheries focus is fourfold: to produce as many kokanee as they can from the spawning channel, manage the IHN virus, continue to fertilize Kootenay Lake, and monitor to monitor rainbow trout escapement and bull trout numbers on the lake. But until stocks rebound, anglers will have to ride out the troughs and patiently await the peak of Mother Nature’s cycle.
“At this point, given the (Gerrard) escapement numbers we’re not hugely concerned from a conservation standpoint,” added Neufeld. “But when catch-rates are low, it is tough to run a successful derby.”